| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Materials selection | 材料选择 |
The process of selecting the most suitable material for a particular application. In the case of solid materials, it involves assessment of candidate materials in terms of their physical properties (density, elastic moduli, fracture toughness, yield strength, hardness, fatigue resistance, coefficient of thermal expansion, thermal conductivity, resistance to thermal shock, creep resistance, corrosion resistance, radiation resistance, etc), and such factors as the function of the final product, its shape, method of manufacture, required tolerances, number to be made, ease of inspection and quality control, cost, and design methodology employed. 为特定应用选择最合适材料的过程。对于固体材料，它涉及根据其物理特性（密度、弹性模量、断裂韧性、屈服强度、硬度、抗疲劳性、热膨胀系数、导热系数、抗热冲击性、抗蠕变性、耐腐蚀性、抗辐射性等）评估候选材料，以及诸如最终产品的功能、其形状、制造方法、所需公差、制造数量、检查和质量控制的容易程度、成本和采用的设计方法等因素。 |
| Elastic deformation | 弹性变形 |
A change in dimensions directly proportional to and in phase with an increase or decrease in applied force. 尺寸的变化与施加的力的增加或减少成正比并同相。 |
| Effective length of a bolt | 螺栓的有效长度 |
The grip length plus some portion of the bolt (often one-half of the thickness of the nuts) which lies within the nut(s) plus some portion (often one-half the thickness) of the head. 握持长度加上位于螺母内的螺栓的某些部分（通常是螺母厚度的二分之一）加上头部的某些部分（通常是厚度的二分之一）。 |
| Secant modulus | 割线模量 |
The slope of the secant drawn from the origin to any specified point on a stress-strain curve. Compare with chord modulus. 从原点到应力应变曲线上任何指定点的割线斜率。与弦模量进行比较。 |
| Thermodynamic state | 热力学状态 |
The condition of a system or working fluid according to its properties. 系统或工作流体根据其性质的状态。 |
| Stead’s brittleness | 斯特德脆性 |
A condition of brittleness that causes transcrystalline fracture in the coarse grain structure that results from prolonged annealing of thin sheets of low-carbon steel previously rolled at a temperature below about 705 °C (1300 °F). The fracture usually occurs at about 45° to the direction of rolling. 一种脆性状态，导致粗晶结构中发生穿晶断裂，这是由于之前在低于约705°C（1300°F）的温度下轧制的低碳钢薄板经过长时间退火造成的。断裂通常发生在与轧制方向约45°处。 |
| Surface hardening | 表面硬化 |
A generic term covering several processes applicable to a suitable ferrous alloy that produces, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are carbonitriding, carburizing, induction hardening, flame hardening, nitriding, and nitrocarburizing. Use of the applicable specific process name is preferred. 一个通用术语，涵盖适用于仅通过淬火硬化产生比型芯更硬或更耐磨的表面层的合适铁合金的几种工艺。表面层的化学成分没有显著改变。常用的工艺有碳氮共渗、渗碳、感应淬火、火焰淬火、氮化和氮碳共渗。最好使用适用的特定工艺名称。 |
| Wrap-around bend | 环绕弯曲 |
The bend obtained when a specimen is wrapped in a closed helix around a cylindrical mandrel. This term is sometimes applied to a semiguided bend of 180° or less. 当试样缠绕在圆柱形心轴周围的闭合螺旋中时获得的弯曲。该术语有时适用于180°或更小的半导弯曲。 |
| Creep modulus (Unit Pa) | 蠕变模量（单位Pa） |
The ratio of stress/strain at a chosen strain level obtained from creep tests, often plotted against time to show changes in stiffness. 从蠕变测试中获得的选定应变水平下的应力/应变比，通常随时间绘制以显示刚度的变化。 |
| Shoulder bolt | 轴肩螺栓 |
A bolt for which the unthreaded cylindrical section between the thread and the head is of larger diameter than the threaded section, precisely machined to length and diameter and hardened 一种螺栓，其螺纹和头部之间的无螺纹圆柱段的直径大于螺纹段的直径，精确加工至长度和直径并硬化 |
| Transition metals | 过渡金属 |
Metallic elements from groups (columns) 3 to 12 of the periodic table. They include important metals such as titanium, vanadium, chromium, manganese, iron, cobalt, zirconium, niobium, molybdenum, tantalum, tungsten, and the noble metals. They have either body-centred cubic, face-centred cubic, or hexagonal close-packed crystal structure at room temperature and have a wide range of mechanical and physical properties. 元素周期表第3组至第12组（列）中的金属元素。它们包括重要的金属，如钛、钒、铬、锰、铁、钴、锆、铌、钼、钽、钨和贵金属。它们在室温下具有体心立方、面心立方或六方密排晶体结构，并具有广泛的机械和物理性能。 |
| Vapour | 蒸气 |
The gas-like phase of a substance at a temperature below its critical point. A vapour can be condensed to a liquid or a solid by increasing its pressure or reducing its temperature. 温度低于临界点的物质的类气相。蒸汽可以通过增加压力或降低温度冷凝成液体或固体。 |
| Compressor bleed | 压缩机排气 |
The removal of air before the final stage of a multistage compressor operating below design speed, to prevent the final stage from choking. 在低于设计速度运行的多级压缩机的末级之前去除空气，以防止末级阻塞。 |
| Apparent area of contact | 表观接触面积 |
In tribology, the area of contact between two solid surfaces defined by the boundaries of their macroscopic interface. 在摩擦学中，两个固体表面之间的接触区域由其宏观界面的边界定义。 |
| Auxetic materials | 拉胀材料 |
Those man-made materials for which Poisson’s ratio is negative, so that the cross section expands when subjected to a longitudinal tensile stress and contracts when subjected to a longitudinal compressive stress. 泊松比为负的人造材料，其横截面在受到纵向拉应力时会膨胀，在受到纵向压应力时会收缩。 |
| Acceleration due to gravity | 重力加速度 |
(acceleration of free fall, gravitational acceleration, g) (Unit m/s²) The acceleration of a freely-falling body in a vacuum, with a mean value at sea level of approximately 9.81 m/s². （自由落体加速度，重力加速度，g）（单位m/s²）自由落体在真空中的加速度，在海平面处的平均值约为9.81m/s²。 |
| Thermal reactor | 热反应器 |
An enlarged exhaust manifold bolted directly to the cylinder head of a piston engine, in which the oxidation of carbon monoxide and unburned hydrocarbons in the exhaust gas is enhanced. 一种扩大的排气歧管，直接用螺栓固定在活塞式发动机的气缸盖上，其中一氧化碳和未燃烧碳氢化合物的氧化作用增强。 |
| Initial strain | 初始应变 |
The strain in a specimen immediately upon achieving the given loading conditions in a creep test (before creep occurs). Sometimes referred to as instantaneous strain. 在蠕变试验中（蠕变发生之前）达到给定载荷条件后，试样立即产生的应变。有时称为瞬时应变。 |
| Silky fracture | 丝状断口 |
A metal fracture in which the broken metal surface has a fine texture, usually dull in appearance. Characteristic of tough and strong metals. 一种金属断裂，断裂的金属表面具有精细的纹理，通常外观暗淡。具有坚韧和坚固金属的特征。 |
| Thermodynamic process | 热力学过程 |
A change in equilibrium state undergone by a quantity of matter or a system. 一定量的物质或系统所经历的平衡状态的变化。 |
| Strength of materials | 材料强度 |
A confusing name for what is really stress analysis, reflecting older engineering design based upon elasticity and ‘theories of strength’ for different materials, without regard to cracks. 对于真正的应力分析，这是一个具有迷惑性的名称，反映了基于弹性和不同材料的“强度理论”的旧工程设计，而不考虑断裂。 |
| Double aging | 双级时效 |
Employment of two different aging treatments to control the type of precipitate formed from a supersaturated matrix in order to obtain the desired properties. The first aging treatment, sometimes referred to as intermediate or stabilizing, is usually carried out at higher temperature than the second. 采用两种不同的时效处理来控制由过饱和基质形成的沉淀物类型，以获得所需的性能。第一次时效处理，有时称为中间处理或稳定处理，通常在比第二次更高的温度下进行。 |
| Piston pump | 活塞泵 |
A positive-displacement pump in the basic configuration of which a piston reciprocates in a cylinder. On the suction stroke, fluid is drawn into a chamber through the inlet valve, which is then open while the outlet valve is closed. On the delivery stroke the fluid is forced out of the chamber through the outlet valve, which then opens while the inlet valve is closed. Both axial and radial configurations are common. 活塞在气缸中往复运动的一种容积泵。在吸入冲程，流体通过入口阀吸入腔室，然后在出口阀关闭时打开。在输送冲程中，流体通过出口阀被迫流出腔室，然后出口阀打开，同时入口阀关闭。轴向和径向配置都很常见。 |
| Fracture mechanisms | 断裂机制 |
The microstructural mechanisms that cause fracture, such as void initiation, growth and coalescence, cleavage. 导致断裂的微观结构机制，如空隙的萌生、生长和聚结、解理。 |
| Total carbon | 总碳 |
The sum of the free and combined carbon (including carbon in solution) in a ferrous alloy. 铁合金中游离碳和结合碳（包括溶液中的碳）的总和。 |
| Lathe | 车床 |
A machine tool in which work, gripped in the headstock, is rotated against the cutting tool to produce turned, bored, faced, or threaded components. 一种机床，其中夹持在主轴箱中的工件靠着切削工具旋转，以生产车削、钻孔、端面或螺纹部件。 |
| Stator | 定子 |
A ring of non-rotating blades or nozzles in a compressor, turbine, or other turbomachine, which directs fluid flow into an adjacent rotor. 涡轮压缩机、涡轮或其他涡轮机械中的一圈不旋转的叶片或喷嘴，将流体引导到相邻的转子中。 |
| Octane number | 辛烷值 |
(octane rating) A measure of the anti-knock properties of a fuel taken as the percentage by volume of iso-octane in the fuel. （辛烷值）以燃料中异辛烷的体积百分比表示的燃料抗爆性能的量度。 |
| Radius of bend | 弯曲半径 |
The radius of the cylindrical surface of the pin or mandrel that comes in contact with the inside surface of the bend during bending. For free or semiguided bends to 180° in which a shim or block is used, the radius of bend is one-half the thickness of the shim or block. 在弯曲过程中与弯曲内表面接触的销或心轴的圆柱面半径。对于使用垫片或垫块的180°自由弯曲或半导向弯曲，弯曲半径为垫片或垫板厚度的一半。 |
| Effective yield strength | 有效屈服强度 |
An assumed value of uniaxial yield strength that represents the influence of plastic yielding on fracture test parameters. 单轴屈服强度的假设值，代表塑性屈服对断裂试验参数的影响。 |
| Vacuum relief valve | 真空安全阀 |
A valve that admits gas to a system under vacuum, should the degree of vacuum become excessive. 如果真空度过高，允许气体在真空下进入系统的阀门。 |
| Cotter pin | 开口销 |
(cotter) 1. A tapered wedge or pin passing through a tapered slot or hole in one member and bearing against a second member to fix it in location. 2. A split cotter is commonly called a split pin. A pin with two legs. With legs together, the pin is placed through the hole in a clevis pin. The legs are then opened outward to prevent the cotter pin from backing out of the hole. The cotter pin, in turn, prevents the load-bearing clevis pin from backing out of its retaining hole. （开口）1.锥形楔子或销钉穿过一个构件中的锥形槽或孔，并支撑在第二个构件上以将其固定到位。2.开口开口通常称为开口销。相当于有两条腿的别针，将支腿放在一起，销钉穿过U形夹销上的孔。然后将支腿向外打开以防止开口销从孔中退出。开口销反过来防止承重U形夹销从其固定孔中退出。 |
| Extra spring | 额外弹簧 |
A temper of nonferrous alloys and some ferrous alloys corresponding approximately to a coldworked state above full hard beyond which further cold work will not measurably increase the strength and hardness. 有色金属合金和一些铁合金的回火状态，大约对应于高于全硬的冷加工状态，超过该状态进一步冷加工将不会显着增加强度和硬度。 |
| Joint space | 关节空间 |
The description of the position and orientation of a robot in terms of the rotational angles and translational positions of the joints. Kinematic analysis, normally using homogeneous transforms, allows conversion between this description and the end‐effector position and orientation in x,y,z space. 根据关节的旋转角度和平移位置描述机器人的位置和方向。通常使用齐次变换的运动学分析允许在该描述与x、y、z空间中的末端执行器位置和方向之间进行转换。 |
| Least count | 最小计数 |
The smallest value that can be read from an instrument having a graduated scale. Except on instruments provided with a vernier, the least count is that fraction of the smallest division which can be conveniently and reliably estimated; this fraction is ordinarily one-fifth or one-tenth, except where the graduations are very closely spaced. 可从具有刻度尺的仪器中读取的最小值。除配备游标的仪器外，最小计数是可以方便可靠地估计的最小除法的分数；这个分数通常是五分之一或十分之一，除非刻度间隔非常近。 |
| Flange rotation | 法兰转角 |
Angular distortion of a flange under the influence of bolt and reaction forces. Measured with respect to the center of the cross section of the flange. 法兰在螺栓和反作用力影响下的角度变形。相对于法兰横截面的中心测量。 |
| Vehicle | 车辆 |
A means of conveyance for transporting goods and people, generally with wheels powered by a petrol, diesel, or steam engine, or by an electric motor, or by a hybrid combination of an electric motor and a diesel or petrol engine. 一种运输货物和人员的交通工具，通常由汽油机、柴油机或蒸汽机、电动机或电动机与柴油机或汽油机的混合动力驱动。 |
| Fillet radius | 圆角半径 |
Concave junction at two intersecting surfaces of a fastener. Often used to describe the junction between the head and the shank of a threaded fastener (under head fillet). 在紧固件的两个相交表面处的凹形接合处。通常用于描述螺纹紧固件的头部和柄部之间的连接处（头部圆角下方）。 |
| Allowable stress design | 许用应力设计 |
A design procedure developed for the AISC by the Research Council on Structural Connections. Purposely underestimates the strengths of bolts and joint materials to introduce safety factors into the design of structural steel joints. It is an alternative to the more recently defined load and resistance factor design procedure. 结构连接研究委员会为AISC制定的设计程序。故意低估螺栓和接头材料的强度，以便在结构钢接头的设计中引入安全系数。它是最近定义的荷载和阻力系数设计程序的替代方法。 |
| Load range, P | 负载范围P |
In fatigue, the algebraic difference between the maximum and minimum loads in a fatigue cycle. 在疲劳中，疲劳循环中最大和最小载荷之间的代数差。 |
| Elastic energy | 弹性能 |
The amount of energy required to deform a material within its elastic range of behavior, neglecting small heat losses due to internal friction. The energy absorbed by a specimen per unit volume of material contained within the gage length being tested. It is determined by measuring the area under the stress-strain curve up to a specified elastic strain. See also modulus of resilience and strain energy. 材料在其弹性行为范围内变形所需的能量，忽略因内耗引起的小热损失。试样在被测标距内每单位体积材料吸收的能量。它是通过测量应力-应变曲线下达到规定弹性应变的面积来确定的。另见弹性模量和应变能。 |
| Erosion | 侵蚀 |
Progressive loss of original material from a solid surface due to mechanical interaction between that surface and a fluid, a multicomponent fluid, or impinging liquid or solid particles. 由于固体表面与流体、多组分流体或撞击液体或固体颗粒之间的机械相互作用，原始材料从固体表面逐渐损失。 |
| Lock nut | 锁紧螺母 |
A type of nut that is prevented from loosening under vibration. The locking action is accomplished by squeezing, gripping or jamming against the bolt threads. A nut which provides extra resistance to vibration loosening (beyond that produced by proper Preload ), either by providing some form of Prevailing torque, or, in free-spinning lock nuts, by deforming, cramping, or biting into mating parts when fully tightened. 1. A thin auxiliary nut tightened against another nut to prevent loosening. 2. A single nut with special features that prevent loosening. 一种在振动下防止松动的螺母。锁定动作通过挤压、夹紧或卡住螺栓螺纹来完成。通过提供某种形式的主要扭矩，或在自由旋转锁紧螺母中，通过完全拧紧时变形、夹紧或咬入配合零件，提供额外的抗振动松动能力（超出适当预载产生的能力）。1.一个薄的辅助螺母，拧紧到另一个螺母上以防止松动。2.具有防止松动的特殊功能的单个螺母。 |
| Zero-gravity | 零重力 |
The situation in which there is no force of gravity (i.e. weightlessness). 没有重力的情况（即失重）。 |
| Damage | 损伤 |
1. The deterioration of a component or structure in fault or accident conditions, reducing or preventing its ability to perform its intended function. 2. The accumulation of defects or microcracks in the microstructure of a body loaded monotonically or in fatigue, which weakens the body and can lead to crack propagation and failure. 1.部件或结构在故障或事故条件下的劣化，降低或阻止其执行预期功能的能力。2.在承受单调载荷或疲劳载荷的物体的微观结构中累积的缺陷或微裂纹，这会削弱物体，并可能导致裂纹扩展和失效。 |
| Inspection gauge | 检验规 |
Any of various gauges used in manufacturing and quality control to check dimensions, finish, etc. 任何用于制造和质量控制的各种量规，以检查尺寸、光洁度等。 |
| Absolute humidity | 绝对湿度 |
The weight of water vapor in a gadwater vapor mixture per unit volume of space occupied, expressed, for example, in grains or pounds per cubic foot. 单位体积空间占用的水蒸气混合物中水蒸气的重量，例如，以谷物或磅/立方英尺表示。 |
| Thermoelectric material | 热电材料 |
A material in which any of the thermoelectric phenomena, such as the Peltier, Seebeck, and Thomson effects, are especially strong. 一种热电现象特别强烈的材料，如珀尔帖效应、塞贝克效应和汤姆森效应。 |
| Direct quenching | 直接淬火 |
(1) Quenching carburized parts directly from the carburizing operation. (2) Also used for quenching pearlitic malleable parts directly from the malleablizing operation. （1） 直接从渗碳作业中淬火渗碳零件。（2） 也用于直接从可锻操作淬火珠光体可锻零件。 |
| Gasket m-factor | 垫片m系数 |
For a gasketed joint of area A in which the clamping force is F, the factor m is defined by F ≥ mpA where p is the pressure that would separate the two halves of the joint and m > 1. 对于面积为A且夹紧力为F的垫片接头，系数m由F≥mpA定义，其中p是分离接头两半的压力，m>1。 |
| Cementite | 渗碳体 |
A compound of iron and carbon, known chemically as iron carbide and having the approximate chemical formula Fe3C. It is characterized by an orthorhombic crystal structure. When it occurs as a phase in steel, the chemical composition will be altered by the presence of manganese and other carbide-forming elements. 碳化铁一种铁和碳的化合物，化学上称为碳化铁，化学式近似为Fe3C。其特征在于正交晶体结构。当它在钢中以相形式出现时，锰和其他碳化物形成元素的存在将改变其化学成分。 |
| Stress equalizing | 应力均衡 |
A low-temperature heat treatment used to balance stresses in cold-worked material without an appreciable decrease in the mechanical strength produced by cold working. 一种低温热处理，用于平衡冷加工材料中的应力，而不会明显降低冷加工产生的机械强度。 |
| Testing machine (load-measuring type) | 试验机（负载测量型） |
A mechanical device for applying a load (force) to a specimen. 向试样施加载荷（力）的机械装置。 |
| Metallurgy | 冶金 |
The study of the atomic, crystallographic, microstructural, mechanical, and physical properties of metallic elements and alloys and their applications. 研究金属元素和合金的原子、晶体学、微观结构、机械和物理特性及其应用。 |
| Partial annealing | 不完全退火 |
An imprecise term used to denote a treatment given cold-worked material to reduce the strength to a controlled level or to effect stress relief. To be meaningful, the type of material, the degree of cold work, and the time-temperature schedule must be stated. 一个不精确的术语，用于表示冷加工材料的处理，以将强度降低到受控水平或消除应力。为了有意义，必须说明材料类型、冷加工程度和时间-温度计划。 |
| Impact extrusion | 冲击挤压 |
The extrusion of separate components of soft metals whose properties permit the action to be performed quickly. 挤压单独的软金属组件，其特性允许快速执行操作。 |
| Total combustion air (Unit kg/s) | 总燃烧空气（单位：kg/s） |
1. The combination of the stoichiometric flow of air required for combustion together with any excess air. 2. The flow of fresh air into a boiler plus any flue gas recirculated. 1.燃烧所需的化学计量空气流与任何过量空气的组合。2.进入锅炉的新鲜空气流加上再循环的任何烟气。 |
| Sharp-notch strength | 锐缺口强度 |
The notch tensile strength measured using specimens with very small notch root radii (approaching the limit for machining capability); values of sharp-notch strength usually depend on notch root radius. 使用缺口根部半径非常小（接近加工能力极限）的试样测量的缺口抗拉强度；锐缺口强度值通常取决于缺口根部半径。 |
| Turbomolecular pump | 涡轮分子泵 |
A high-vacuum (pressure down to about 10−8 Pa) pump in which momentum is transferred to the gas molecules by a rapidly rotating bladed disc. 高真空（压力降至约10−8Pa）泵，其中动量通过快速旋转的叶片盘传递给气体分子。 |
| Charles law/Charles' law | 查尔斯定律 |
(Gay–Lussac law) The volume of a fixed mass of gas at constant pressure is proportional to its absolute temperature. The volume of a gas at constant pressure is directly proportional to its absolute temperature. （盖-吕萨克定律）在恒定压力下，固定质量气体的体积与其绝对温度成正比。恒压下气体的体积与其绝对温度成正比。 |
| End-quench hardenability test | 端淬淬透性试验 |
A laboratory procedure for determining the hardenability of a steel or other ferrous alloy. Hardenability is determined by heating a standard specimen above the upper critical temperature, placing the hot specimen in a fixture so that a stream of cold water impinges on one end, and, after cooling to room temperature is completed, measuring the hardness near the surface of the specimen at regularly spaced intervals along its length. The data are normally plotted as hardness versus distance from the quenched end. 测定钢或其他铁合金淬透性的实验室程序。淬透性是通过将标准试样加热到高于上临界温度，将热试样放置在夹具中，使冷水流冲击一端，并在冷却至室温后，沿试样长度以规则间隔测量试样表面附近的硬度来确定的。数据通常绘制为硬度与距淬火端距离的关系。 |
| Normality | 常态 |
The principle that the vector sum of plastic strain increments is perpendicular to the yield surface. 塑性应变增量矢量和垂直于屈服面的原理。 |
| Normalizing | 正火 |
Heating a ferrous alloy to a suitable temperature above the transformation range and then cooling in air to a temperature substantially below the transformation range. 将铁合金加热至高于转变范围的合适温度，然后在空气中冷却至基本低于转变范围的温度。 |
| Angle of friction | 摩擦角 |
(friction angle, β) (Unit °) For a body in contact with a plane surface, the angle between the normal to the surface and the resultant force between the body and the surface. If the friction force is F and normal force is N, β is given by F/N = μ = tan β where μ is the coefficient of friction. （摩擦角，β）（单位°）对于与平面接触的物体，表面法线与物体与表面之间的合力之间的夹角。如果摩擦力为F，法向力为N，则β由F/N=μ=tanβ给出，其中μ是摩擦系数。 |
| Pascal (Pa) | 帕斯卡（Pa） |
The SI unit of pressure, 1 Pa = 1 N/m². 压力的国际单位制，1Pa=1N/m²。 |
| Edge distance ratio | 边距比 |
The ratio of the edge distance to the pin diameter in a bearing test. 轴承测试中边缘距离与销直径的比值。 |
| Minimum load (Pmin) | 最小负载（Pmin） |
In fatigue, the least algebraic value of applied load in a cycle. 在疲劳中，循环中施加载荷的最小代数值。 |
| Yield-point elongation | 屈服点延伸 |
During discontinuous yielding, the amount of strain measured from the onset of yielding to the beginning of strain hardening. 在不连续屈服期间，从屈服开始到应变硬化开始测量的应变量。 |
| Wedge | 楔子 |
A short triangular prism whose major surfaces subtend an acute angle, that can be driven between two objects or parts of an object to split, tighten, or secure them, or to widen an opening or raise a heavy object. The acute angle gives a high mechanical advantage. 一种短的三棱镜，其主面对着一个锐角，可在两个物体或物体的一部分之间驱动，以将它们分开、拧紧或固定，或加宽开口或举起重物。锐角具有很高的机械优势。 |
| Black annealing | 黑退火 |
Box annealing or pot annealing ferrous alloy sheet, strip, wire to impart a black color to the oxidized surface. 对铁合金板、带、线进行箱式退火或罐式退火，使氧化表面呈黑色。 |
| Hydraulics | 液压系统 |
The study of water flow in open channels (including canals, rivers, etc.), water-supply, drainage, and irrigation systems. 研究明渠（包括运河、河流等）、供水、排水和灌溉系统中的水流。 |
| Structural analysis | 结构分析 |
The determination of the forces, displacements, stresses, and strains in a given structure. 确定给定结构中的力、位移、应力和应变。 |
| Collar | 圈、箍 |
A ring secured to, or integral with, a shaft to give axial location. 固定在轴上或与轴成一体以提供轴向位置的环。 |
| Creep limit (Unit Pa) | 蠕变极限（单位Pa） |
The maximum allowable stress under the action of which creep deformation of a material does not exceed a specified limit. 材料在其作用下的蠕变变形不超过规定限度的最大许用应力。 |
| Pop rivet | 拉钉 |
A hollow rivet that enables a connexion to be made from one side only of an assembly. 一种空心铆钉，使连接只能从组件的一侧进行。 |
| Critical temperature | 临界温度 |
(1) Synonymous with critical point if the pressure is constant. (2) The temperature above which the vapor phase cannot be condensed to liquid by an increase in pressure. （1） 如果压力恒定，则与临界点同义。（2） 高于该温度时，气相不能通过压力升高而冷凝为液体。 |
| Torricellean barometer | 托里塞莱气压计 |
A vertical glass tube with its upper end sealed and the lower end submerged in a pool of mercury. The space above the mercury is under vacuum. The height to which the mercury rises up the tube is a measure of the barometric pressure. 一种垂直的玻璃管，上端密封，下端浸入汞池中。水银上方的空间处于真空状态。水银在管道中上升的高度是大气压力的量度。 |
| Joint | 关节接合处 |
The part of a robot arm permitting either rotational or translational motion. Each joint provides a single degree of freedom, and thus a minimum of six is required if the robot is to be able to position and orientate the end effector anywhere within the workspace. A joint is described by four parameters: the joint angle, joint offset, joint twist, and link length. The joint angle is the angle between an extrapolation of the previous link length and the present link length, measured positive anticlockwise in a plane normal to the joint axis. This is variable in a rotational joint and fixed in a translational joint. The joint offset is the distance between the link length for the previous link and that for the present link, measured along the joint axis. This is variable for a translational joint and fixed for a rotational joint. The joint twist for the nth joint is the angle between the axes of joints Jn and Jn+1, measured positive anticlockwise in a plane normal to the link length and viewed from the position of the Jn+1 joint. The link length is the mutually perpendicular distance between planes passing through the axes of joint Jn and Jn+1. Both the joint twist and link length are fixed in all joints. 机器人手臂上允许旋转或平移运动的部分。每个接合处都有自由度，如果机器人要能够在工作空间内的任何位置定位和定向末端执行器，则至少需要六个接合处具有自由度。关节接合处由四个参数描述：关节角度、关节偏移、关节扭曲和链接长度。关节角度是在垂直于关节轴的平面内逆时针测量的先前连杆长度和当前连杆长度的外推之间的角度。这在旋转关节中是可变的，在平移关节中是固定的。关节偏移是沿关节轴测量的前一个连杆和当前连杆的连杆长度之间的距离。这对于平移关节是可变的，对于旋转关节是固定的。第n个关节的关节扭曲是关节Jn和Jn+1轴之间的角度，在垂直于连杆长度的平面内逆时针测量，从Jn+2关节的位置观察。连杆长度是穿过关节轴Jn和Jn+1的平面之间相互垂直的距离。关节扭曲和连杆长度在所有关节中都是固定的。 |
| Population | 集合 |
The hypothetical collection of all possible test specimens that could be prepared in the specified way from the material under consideration. Also known as universe. 从所考虑的材料中以规定方式制备的所有可能试样的假设集合。也称为体系。 |
| Screw conveyor | 螺旋输送机 |
(auger, spiral conveyor, worm conveyor) A machine for bulk handling of semi-solid materials, consisting of a helical screw which rotates in a trough or casing. （螺旋输送机、螺旋输送机、蜗杆输送机）一种用于散装搬运半固态材料的机器，由在槽或外壳中旋转的螺旋螺杆组成。 |
| Torque multiplier | 扭矩放大器 |
A gearbox used to multiply the torque produced by a small hand wrench (usually a Torque wrench). The output of the multiplier drives the nut or bolt with a torque that is higher, and a speed that is lower, than input torque and speed. There is no torque gage or readout on the multiplier. 一种齿轮箱，用于增加小手动扳手（通常是扭矩扳手）产生的扭矩。倍增器的输出以比输入扭矩和速度更高的扭矩和更低的速度驱动螺母或螺栓。倍增器上没有扭矩计或读数。 |
| Outside diameter (Unit m) | 外径（单位：m） |
(external diameter, OD) The diameter of a circular cylindrical tube or a sphere measured between opposite points on the external surface. （外径，OD）在外表面上的相对点之间测量的圆柱管或球体的直径。 |
| Celsius | 摄氏度 |
The temperature scale based on the freezing point of water (0ºC) and the boiling point of water (100ºC). The interval between these points is divided into 100 degrees. The scale was devised by Anders Celsius. 基于水的冰点（0ºC）和水的沸点（100ºC）的温标。这些点之间的间隔被划分为100度。这个比例是由安德斯·摄氏设计的。 |
| Net weight (Unit N) | 净重（单位：N） |
The difference between the gross weight of any container including its contents and the tare weight of the empty container. 任何容器（包括其内容物）的毛重与空容器皮重之间的差值。 |
| Normal temperature and pressure (NTP) | 常温常压（NTP） |
Reference conditions defined by NIST as 20°C and 1 atm. NIST定义的参考条件为20°C和1atm。 |
| V-block | V型块 |
A block having a 90° V-shaped recess; used in a workshop to hold round workpieces. 具有90°V形凹槽的块体；在车间里用来装圆形工件。 |
| Gasket stress | 垫片应力 |
The contact stress exerted on the gasket by the joint members. 连接件施加在垫片上的接触应力。 |
| Single-shear test | 单剪试验 |
(1) A shear test similar to the double-shear test used for round-bar specimens, but that uses only one stationary shear blade. (2) A shear test that uses a sheet or thin-plate specimen. （1）一种剪切试验，类似于用于圆棒试样的双剪切试验，但仅使用一个固定剪切刀片。（2）使用薄板或薄板试样的剪切试验。 |
| Fracture test | 断裂试验 |
A test in which a specimen is broken and its fracture surface is examined with the unaided eye or with a low-power microscope to determine such factors as composition, grain size, case depth, or internal discontinuities. 1. The recording of load-deflexion (or stress–strain) in a specimen loaded monotonically until it breaks in tension, compression, shear, or torsion. 2. In fatigue, determination of the number of cycles to fracture for a specimen under different patterns of repeated loading. 3. Experiments to determine fracture toughness. 一种试验，其中试样被破坏并用肉眼或低倍显微镜检查其断裂表面，以确定成分、晶粒尺寸、表层深度或内部不连续性等因素。1.记录单调加载试样的载荷偏转（或应力-应变），直到其在拉伸、压缩、剪切或扭转中断裂。2.在疲劳技术中，确定试样在不同重复载荷模式下的断裂循环次数。3.测定断裂韧性的实验。 |
| Critical load (Unit N) | 临界负荷（单位N） |
1. The applied load that causes propagation of an existing crack of known length, and hence fracture of a component or structure. 2. The applied load that results in buckling of a column of given end fixity. 1.导致已知长度的现有裂纹扩展并因此导致部件或结构断裂的施加荷载。2.导致具有给定端部固定性的柱屈曲的施加荷载。 |
| Pitch angle (Unit °) | 俯仰角（单位°） |
For a bevel gear, the angle between the axis and the pitch-cone generator. 对于锥齿轮，轴与节锥生成器之间的角度。 |
| Strain energy | 应变能 |
A measure of the energy absorption characteristics of a material determined by measuring the area under the stress-strain diagram. 通过测量应力-应变图下的面积确定的材料能量吸收特性的度量。 |
| Annealing twin | 退火孪晶 |
A twin form in a crystal during recrystallization. 重结晶过程中晶体中的孪晶形式。 |
| Centrifugal | 离心式 |
Acting or moving in a direction away from the axis of rotation of a rotating body. 沿远离旋转体的旋转轴的方向作用或移动。 |
| Absolute viscosity | 绝对粘度 |
A measure of the internal shear properties of fluids, expressed as the tangential force per unit area at either of two horizontal planes separated by one unit thickness of a given fluid, one of the planes being fixed and the other moving with unit velocity. 流体内部剪切特性的量度，表示为两个水平面中的任何一个上的单位面积切向力，两个水平面被给定流体的一个单位厚度隔开，其中一个平面固定，另一个以单位速度移动。 |
| Dynamics | 动力学 |
The branch of mechanics that deals with objects in motion. Its two main branches are kinematics, which studies motion without regards to its cause, and kinetics, which also takes into account forces that cause motion. 力学中研究运动物体的分支。它的两个主要分支是运动学和动力学，前者研究运动而不考虑其原因，后者也考虑引起运动的力。 |
| Maximum stress-intensity factor (Kmax) | 最大应力强度因子（Kmax） |
The maximum value of the stress-intensity factorin a fatigue cycle. 疲劳循环中应力强度因子的最大值。 |
| Expansion bolt | 膨胀螺栓 |
When a through bolt cannot be used for attaching a pipe hanger, bracket, or other part, to a wall or ceiling of brick or concrete, what are known as expansion bolts are often used. The body of an expansion bolt is divided and the arrangement is such that, when the head of the bolt is turned, the sections forming the body of the bolt are forced outward and against the wall of the hole which has been drilled into the brick, concrete, or stone, as the case may be. Bolts of this type are made in quite a variety of designs. The nominal size represents the diameter of the bolt proper and not the diameter of the casing or expansion member. 当不能使用贯穿螺栓将管道吊架、支架或其他部件连接到砖块或混凝土的墙壁或天花板时，通常使用所谓的膨胀螺栓。膨胀螺栓的主体是分开的，其布置方式是，当螺栓头转动时，形成螺栓主体的部分被强制向外并靠在已钻入砖、混凝土或石头中的孔壁上，视情况而定。这种类型的螺栓有多种设计。标称尺寸代表螺栓本身的直径，而不是套管或膨胀构件的直径。 |
| Cold treatment | 冷处理 |
Treatment carried out after quenching to transform retained austenite into martensite, involving cooling and holding at a temperature below ambient. 淬火后进行的处理，以将残余奥氏体转变为马氏体，包括冷却和保持在低于环境温度的温度。 |
| Fatigue test | 疲劳测试 |
A method for determining the range of alternating (fluctuating)stresses a material can withstand without failing. 一种确定材料可以承受而不会失效的交变（波动）应力范围的方法。 |
| Load factor (F) | 负载系数（F） |
The ratio between an increase in bolt tension and the external load which has caused the increase. Factors reflecting the probability of an increase in load in a shear joint. Used in load and resistant factor design. 螺栓张力增加与导致增加的外部载荷之间的比率。反映剪切接缝中荷载增加概率的系数。用于载荷和阻力系数设计。 |
| Poisson’s ratio (ν) | 泊松比（ν） |
The absolute value of the ratio of transverse (lateral) strain to the corresponding axial strain resulting from uniformly distributed axial stress below the proportional limit of the material. 横向（侧向）应变与相应轴向应变之比的绝对值，该比值由低于材料比例极限的均匀分布的轴向应力产生。 |
| Sample variance (s²) | 样本方差（s²） |
The sum of the squares of the differences between each observed value and the sample average divided by the sample size minus one. It is a point estimate of the population variance. 每个观测值与样本平均值之差的平方和除以样本大小减1。它是总体方差的点估计。 |
| Sample average | 样本平均值 |
The sum of all the observed values in a sample divided by the sample size. It is a point estimate of the population mean. Also known as arithmetic mean. 样本中所有观察值的总和除以样本大小。它是总体平均值的点估计。也称为算术平均值。 |
| Tear strength (Unit N/m) | 撕裂强度（单位：N/m） |
The tensile force divided by the sheet thickness required to tear a pre-split sheet material at a specified rate. Particularly used for plastics, rubber, fabrics, and elastomers. Since the units are not those of stress but equivalent to J/m², the units of toughness, the term ‘strength’ is strictly incorrect. 按规定速率撕裂预裂片材所需的张力除以片材厚度。特别用于塑料、橡胶、织物和弹性体。由于单位不是应力单位，而是相当于J/m²，韧性单位，“强度”一词是完全错误的。 |
| Rolled thread | 滚制螺纹 |
A thread formed by plastically deforming the surface of the blank rather than by cutting operations. Increases fatigue life and thread strength, but is not possible (or perhaps economical) on larger sizes. 通过塑性变形坯料表面而不是通过切割操作形成的螺纹。增加疲劳寿命和螺纹强度，但不太可能（或者说是经济上不太可能）用于较大的尺寸。 |
| Coextrusion | 复合挤压 |
The simultaneous extrusion through the same die of two or more materials in combination. 通过同一模具同时挤出两种或多种材料的组合。 |
| Condensation shock | 冷凝冲击 |
For supersonic flow of a moist gas through a divergent nozzle, condensation occurs in the form of spontaneous nucleation at some point downstream of that at which the temperature falls to the saturation temperature. The condensation process proceeds rapidly, and results in a fairly thick discontinuity termed a condensation shock. 对于通过发散喷嘴的湿气体超音速流动，在温度降至饱和温度的点下游的某个点处，冷凝以自发成核的形式发生。凝结过程进行得很快，导致相当厚的不连续性，称为凝结激波。 |
| Captive nut | 松脱螺母 |
A nut attached loosely or rigidly to a sheet member that is too thin to thread and which engages with a cap screw. 松脱地或刚性地连接到薄板构件上的螺母，该螺母太薄而无法拧入，并与带帽螺钉接合。 |
| Residual preload | 残余预载荷 |
The tension which remains in an unloaded bolted joint after Relaxation. 松弛后未加载螺栓连接中保持的张力。 |
| Inch (in) | 英寸（in） |
A non-SI unit of length now defined as 25.4 mm. The conversion to SI is 1 in = 2.54 × 10−2 m. 现在定义为25.4毫米的非SI长度单位。转换为SI为1in=2.54×10-2m。 |
| Wind pressure (Unit Pa) | 风压（单位Pa） |
The dynamic pressure associated with the wind. The static pressure of the wind is the atmospheric pressure. 与风相关的动态压力。风的静压是大气压。 |
| Crest | 波峰 |
The highest point of a wave or of a screw thread. 波浪或螺纹的最高点。 |
| Residual stress (Unit Pa) | 残余应力（单位Pa） |
Stresses that remain within a body as the result of thermal or mechanical treatment or both. (internal stress) An internal-stress system found in components that have experienced elastic unloading from non-uniform plastic-strain fields during manufacture. 由于热处理或机械处理或两者兼而有之而留在物体内的应力。（内应力）在制造期间从非均匀塑性应变场经历弹性卸载的部件中发现的内应力系统。 |
| Batch furnace | 间歇式炉 |
A furnace used to heat treat a single load at a time. Batch-type furnaces are necessary for large parts such as heavy forgings and are preferred for complex alloy grades requiring long cycles. 用于一次热处理单个负载的炉子。对于重型锻件等大型零件，间歇式炉是必需的，对于需要长周期的复杂合金牌号来说是首选。 |
| Rotary piston flow meter | 旋转活塞流量计 |
A rotary liquid flow meter in which a cylindrical rotor, eccentrically mounted within a cylindrical casing, the axes of the two cylinders being parallel, is caused to rotate by the liquid flow. The flow rate is determined from the number of rotations of the rotor in a given time. 一种旋转式液体流量计，其中偏心安装在圆柱形外壳内的圆柱形转子，两个圆柱体的轴线平行，由液体流引起旋转。流量由转子在给定时间内的转数确定。 |
| Significance level | 显着性水平 |
The stated probability (risk) that a given test of significance will reject the hypothesis that a specified effect is absent when the hypothesis is true. 当假设为真时，给定的显著性检验将拒绝特定效应不存在的假设的所述概率（风险）。 |
| Available head (Unit m) | 可用水头（单位米） |
In a hydroelectric power system, the difference between the vertical height of the water level in the supply reservoir above the turbine inlet less the head loss due to friction and fittings in the duct leading to the turbine. 在水力发电系统中，水轮机入口上方供水水库中水位垂直高度之间的差减去由于通向涡轮机的管道中的摩擦和配件造成的水头损失。 |
| Bearing yield strength | 轴承屈服强度 |
The bearing stress at which a material exhibits a specified limiting deviation from the proportionality of bearing stress to bearing strain in a bearing test. 在轴承测试中，材料在轴承应力与轴承应变的比例之间表现出特定的极限偏差时的轴承应力。 |
| Bernoulli’s law | 伯努利定律 |
For a steadily flowing fluid (liquid or gas), the sum of the pressure, kinetic energy per unit volume and potential energy per unit volume is constant at any point in the fluid. Using this relationship, it is possible to measure the velocity of a fluid by measuring its pressure at two points, as with a manometer or Pitot tube. 对于稳定流动的流体（液体或气体），压力、每单位体积的动能和每单位体积的势能之和在流体中的任何点都是恒定的。使用这种关系，可以通过在两个点测量流体的压力来测量流体的速度，就像使用压力计或皮托管一样。 |
| Heat treatment | 热处理 |
(heat treating) Alteration of the mechanical properties of materials, particularly metals, by different sequences of heating, holding at temperature, and cooling at different rates. Heating and cooling a solid metal or alloy in such a way as to obtain desired conditions or properties. Heating for the sole purpose of hot working is excluded from the meaning of this definition. （热处理）材料，特别是金属的机械性能的改变，通过不同的加热顺序、温度保持和不同速率的冷却。加热和冷却固体金属或合金，以获得所需的条件或性能。仅用于热加工的加热不属于本定义的含义。 |
| Austenitizing | 奥氏体化 |
Forming austenite by heating a ferrous alloy into the transformation range (partial austenitizing) or above the transformation range (complete austenitizing). When used without qualification, the term implies complete austenitizing. 通过将铁合金加热到转变范围（部分奥氏体化）或高于转变范围（完全奥氏体化）来形成奥氏体。当不加限定地使用时，该术语意味着完全奥氏体化。 |
| Gibbs–Dalton law | 吉布斯-道尔顿定律 |
An extension of Dalton’s law of additive pressures to include the statement that the internal energy, enthalpy, and entropy of a mixture of gases are equal to the sum of the internal energies, enthalpies, and entropies the individual constituents would have if each existed alone at the same temperature and volume. Gibbs rule is that part of the law pertaining to entropy. 道尔顿附加压力定律的扩展，包括以下陈述：气体混合物的内能、焓和熵等于各个成分单独存在时的内能、焓和熵之和。相同的温度和体积。吉布斯定律是与熵有关的定律的一部分。 |
| Fastener | 紧固件 |
A fastener is a mechanical device for holding two or more bodies in definite positions with respect to each other. 紧固件是一种机械装置，用于将两个或多个物体相对于彼此固定在确定的位置。 |
| Starting friction | 起动摩擦 |
(limiting friction, static friction, stiction) (Unit N) The force required to initiate movement between two bodies in contact. （极限摩擦力、静摩擦力、粘滞）（单位N）在两个接触物体之间启动运动所需的力。 |
| Transverse direction | 横向 |
Literally, the “across” direction, usually signifying a direction or plane perpendicular to the direction of working. In rolled plate or sheet, the direction across the width is often called long transverse, and the direction through the thickness, short transverse. 从字面上看，“横穿”方向，通常表示与工作方向垂直的方向或平面。在轧制钢板或薄板中，横跨宽度的方向通常称为长横向，穿过厚度的方向称为短横向。 |
| Hypereutectic alloy | 过共晶合金 |
In an alloy system exhibiting a eutectic, any alloy whose composition has an excess of alloying element compared with the eutectic composition, and whose equilibrium microstructure contains some eutectic structure. 在呈现共晶的合金系统中，任何合金，其组成与共晶组成相比具有过量的合金元素，并且其平衡微观结构包含一些共晶结构。 |
| Seal | 密封件 |
A component which controls or prevents leakage of fluids into or out of parts of a machine. 控制或防止流体流入或流出机器部件的部件。 |
| Oxidized surface (on steel) | 氧化表面（在钢上） |
Surface having a thin, tightly adhering, oxidized skin (from straw to blue in color), extending in from the edge of a coil or sheet. Sometimes called annealing border. 表面具有薄的、紧密粘附的氧化皮（从稻草色到蓝色），从线圈或薄片的边缘延伸。有时称为退火边界。 |
| Size dimension (Unit m) | 尺寸范围（单位：米） |
The specified value of a diameter, length, width, etc. of a feature required to specify the finished form of a component or assembly. 指定部件或组件的成品形状所需的特征的直径、长度、宽度等的指定值。 |
| Clutch | 离合器 |
A device for connecting and disconnecting rotating shafts, for example between an engine and a gearbox. 一种用于连接和断开旋转轴的装置，例如在发动机和变速箱之间。 |
| Rotary pump | 旋转泵 |
A positive-displacement pump that pumps a liquid by rotation of internal components, such as a gear pump, lobe pump (similar to a Roots blower), or progressivecavity pump. 通过内部部件的旋转来泵送液体的容积泵，如齿轮泵、凸轮泵（类似于罗茨鼓风机）或螺杆泵。 |
| Spalling | 剥落 |
The separation of macroscopic particles from a surface in the form of flakes or chips. 以薄片或碎片形式从表面分离宏观颗粒。 |
| Radial marks | 径向标记 |
Lines on a fracture surface that radiate from the fracture origin and are visible to the unaided eye or at low magnification. Radial lines result from the intersection and connection of brittle fractures propagating at different levels. Also known as shear ledges. 断裂表面上的线，从断裂起点辐射，肉眼可见或在低放大率下可见。径向线是在不同层面上传播的脆性断裂相交和连接的结果。也称为剪切壁架。 |
| Thread form | 螺纹形式 |
The cross-sectional shape of the threads, defining thread angle, root, and crest profiles, etc. Thread length Length of that portion of the fastener which contains threads cut or rolled to full depth. 螺纹的横截面形状，定义螺纹角度、齿根和齿冠轮廓等。螺纹长度：紧固件中包含全深度切割或轧制螺纹的部分的长度。 |
| Dilatometer | 膨胀计 |
An instrument for measuring length or volume changes in a solid during heating and subsequent cooling or isothermal holding. · An instrument for measuring the linear expansion or contraction in a metal resulting from changes in such factors as temperature and allotropy. 一种在加热和随后的冷却或等温保持过程中测量固体长度或体积变化，测量金属因温度和同素异形体等因素的变化而引起的线性膨胀或收缩的仪器。 |
| Brine quenching | 盐水淬火 |
A quench in which brine (salt water-chlorides, carbonates, and cyanides) is the quenching medium. The salt addition improves the efficiency of water at the vapor phase or hot stage of the quenching process. 一种淬火，其中盐水（盐水-氯化物、碳酸盐和氰化物）是淬火介质。添加盐提高了水在淬火过程的气相或热阶段的效率。 |
| Acoustic droplet ejection | 声液滴喷射 |
The ejection of small droplets from the surface of a liquid that results from focusing high-intensity ultrasound near the surface. 由于在表面附近聚焦高强度超声波而从液体表面喷射出小液滴。 |
| Torsional shaft vibration | 扭轴振动 |
The rapid back-and-forth angular twisting along a rotating unbalanced shaft which reaches maxima at critical rotation speeds. Shaft eccentricity, unbalanced mass distribution, oscillatory torque, misalignment, etc. all influence torsional vibration. 沿旋转不平衡轴的快速来回角扭转，在临界转速下达到最大值。轴偏心、质量分布不平衡、振荡扭矩、未对准等都会影响扭转振动。 |
| Notch brittleness | 缺口脆性 |
Susceptibility of a material to brittle fractureat points of stress concentration. For example, in a notch tensile test, the material is said to be notch brittle if the notch strengthis less than the tensile strength of an unnotched specimen. Otherwise, it is said to be notch ductile. 材料在应力集中点易发生脆性断裂。例如，在缺口拉伸试验中，如果缺口强度小于无缺口试样的抗拉强度，则称材料为缺口脆性材料。否则，称其为缺口韧性。 |
| Sizing | 颗粒化 |
1. A finishing operation to ensure the specified dimensions and tolerances for a component are met. 2. (size classification) Separating an aggregate of mixed particles into groups according to size using a series of screens. 1.精加工操作，以确保满足部件的规定尺寸和公差。2.（粒度分类）使用一系列筛网根据粒度将混合颗粒的聚集体分成组。 |
| Preload | 预载 |
The tension created in a threaded fastener when the nut is first tightened. Often used interchangeably, but incorrectly, with Working load or bolt force or bolt tension 第一次拧紧螺母时螺纹紧固件中产生的张力。经常与工作载荷或螺栓力或螺栓张力互换使用但容易使用不当。 |
| Constant-mesh gearbox | 恒啮合齿轮箱 |
A gearbox in which the pairs of gears giving different speed ratios are constantly in mesh, different ratios being obtained by connecting or disconnecting the relevant gear to the driving shaft. 一种齿轮箱，其中提供不同速比的齿轮对始终啮合，通过将相关齿轮连接或断开驱动轴获得不同的速比。 |
| Observed value | 观测值 |
The particular value of a characteristic determined as a result of a test or measurement. 作为测试或测量结果确定的特性的特定值。 |
| Mode of failure | 故障模式 |
The various ways in which a material can fail when subjected to loading, surface damage, chemical attack, heating, cooling, or radiation, in either isolation or combination. The failure modes include fracture, fatigue, creep, corrosion, erosion, and embrittlement. 材料在受到载荷、表面损伤、化学侵蚀、加热、冷却或辐射时，可能发生失效的各种方式，无论是单独还是组合。失效模式包括断裂、疲劳、蠕变、腐蚀、侵蚀和脆化。 |
| Transformation toughening | 相变增韧 |
The improvement of fracture toughness of a material by stress-induced transformation of the microstructure. 通过微结构的应力诱导转变来提高材料的断裂韧性。 |
| Heat-capacity rate (c) (Unit W/K) | 热容率（c）（单位W/K） |
For fluid flow in a duct with mass flow rate ṁ, the product ṁC where C is the specific-heat capacity, at constant pressure (CP) in the case of a gas. 对于质量流量为ṁ的管道中的流体流动，乘积ṁC其中C是比热容，在气体的情况下为恒定压力（CP）。 |
| Total head (hT) (Unit m) | 总水头（hT）（单位：m） |
Total pressure pT expressed in terms of the vertical height of a column of liquid, typically water or mercury, i.e. hT = pT/ρg where g is the acceleration due to gravity and ρ is the liquid density. 总压力pT以液体柱（通常为水或汞）的垂直高度表示，即hT=pT/ρg，其中g为重力加速度，ρ为液体密度。 |
| Tensiometer | 张力计 |
An instrument used to measure surface tension. 用来测量表面张力的仪器。 |
| Flattening test | 压扁试验 |
This term as applied to tubing refers to a method of testing a section of tubing by flattening it until the inside walls are parallel and separated by a given distanceusually equal to three times the wall thickness for seamless tubes and five times the wall thickness for lap-welded tubes. Boiler tubes subjected to this test should show no cracks or flaws. The flattening test applied to rivets, consists in flattening a rivet head while hot to a diameter equal to 21⁄2 times the diameter of the shank or body of the rivet. Good rivet steel must not crack at the edges of the flattened head. 该术语适用于管材，是指通过压扁管材直至内壁平行并隔开给定距离（通常等于无缝钢管壁厚的三倍，搭接焊管壁厚的五倍）来测试管材截面的方法。进行该试验的锅炉管应无裂纹或缺陷。适用于铆钉的压扁试验包括在热态下压扁铆钉头，使其直径等于铆钉柄或铆钉体直径的21⁄2倍。良好的铆钉钢不得在扁平头部边缘开裂。 |
| Bolt blank | 螺栓毛坯 |
A rod on which a head has been formed, but on which no thread has been cut, from which bolts or screws may be made as required. 一种已形成头部但未切割螺纹的杆，可根据需要从中制造螺栓或螺钉。 |
| Dead centre | 止点 |
The point at which, in a crank mechanism, the piston connecting rod and crank are all in line so that there can be no driving moment. 在曲柄机构中，活塞连杆和曲柄都在一条线上，因此不会有驱动力矩。 |
| Grain size | 晶粒大小 |
A measure of the areas or volumes of grains in a polycrystalline metal, usually expressed as an average when the individual sizes are fairly uniform. In metals containing two or more phases, the grain size refers to that of the matrix unless otherwise specified. For metals, a measure of the areas or volumes of grains in a polycrystalline material, usually expressed as an average when the individual sizes are fairly uniform. In metals containing two or more phases, the grain size refers to that of the matrix unless otherwise specified. Grain sizes are reported in terms of number of grains per unit area or volume, average diameter, or as a grainsize number derived from area measurements. 多晶金属中晶粒的面积或体积的量度，通常表示为单个尺寸相当均匀时的平均值。在含有两相或多相的金属中，除非另有说明，晶粒尺寸是指基体的晶粒尺寸。多晶材料中晶粒的面积或体积的量度，通常表示为单个尺寸相当均匀时的平均值。在含有两相或多相的金属中，除非另有说明，晶粒尺寸是指基体的晶粒尺寸。晶粒尺寸以每单位面积或体积的晶粒数、平均直径或从面积测量得出的晶粒尺寸数来报告。 |
| Air-cooled engine | 风冷发动机 |
An internal-combustion engine directly cooled by airflow, rather than by water flowing through the engine block being cooled by a radiator. 一种由气流直接冷却的内燃机，而不是通过流经发动机缸体的水被散热器冷却。 |
| Absolute stability | 绝对稳定 |
Condtion of a linear system in which there exists a limiting value of the open-loop gain such that the system is stable for all lower values of that gain, and unstable for all higher values. 线性系统的条件，其中存在开环增益的限制值，使得系统对于该增益的所有较低值都是稳定的，而对于所有较高值来说都是不稳定的。 |
| Heat tinting | 热着色 |
Coloration of a metal surface through oxidation by heating to reveal details of the microstructure. 通过加热氧化使金属表面着色，以揭示微观结构的细节。 |
| Pulley | 带轮 |
A free or driven wheel on a shaft with an appropriately shaped rim to carry a flat belt, vee belt, notched belt, rope, or chain. Used to transmit power or motion. 轴上的自由轮或从动轮，具有适当形状的轮缘，以承载平皮带、V形皮带、槽口皮带、绳索或链条。用于传递动力或运动。 |
| Relative density | 相对密度 |
(specific gravity) The ratio of the density of a substance to that of a reference substance, such as water for liquids and solids, and dry air for gases. （比重）物质密度与参考物质密度之比，如液体和固体为水，气体为干燥空气。 |
| Crushing strain | 压应变 |
The supposed single strain that results in comminution of a brittle material. The corresponding stress is termed the crushing strength. Neither quantity can be a material constant as they must obey the laws of fracture mechanics and will depend on the type of testpiece, method of loading etc. 导致脆性材料粉碎的假定单应变。相应的应力称为抗压强度。这两个量都不能是材料常数，因为它们必须遵守断裂力学定律，并取决于试件类型、加载方法等。 |
| Annealing | 退火 |
A generic term denoting a treatment, consisting of heating to and holding at a suitable temperature followed by cooling at a suitable rate, used primarily to soften metallic materials, but also to simultaneously produce desired changes in other properties or in microstructure. 一个通用术语，表示一种处理，包括加热并保持在合适的温度，然后以合适的速率冷却，主要用于软化金属材料，但也同时产生其他性能或微观结构的所需变化。 |
| Accelerated testing | 加速测试 |
A type of testing, for rates of wear, fatigue, corrosion etc., in which failure times are reduced by employing greater loads, more frequent power cycling, higher vibration levels, higher humidity, higher temperatures, greater potential differences etc. than would be encountered in normal operation. 一种测试类型，用于测试磨损率、疲劳率、腐蚀率等，通过采用比正常运行中更大的负载、更频繁的功率循环、更高的振动水平、更高湿度、更高温度、更大的电位差等，减少故障时间。 |
| Concentrated load | 集中负荷 |
A load on a component which is distributed over a very small area, idealized as the line load of a wedge or knife edge, and the point load of a cone. 分布在非常小的区域上的部件上的载荷，理想化为楔形或刀刃的线载荷和锥体的点载荷。 |
| Computational domain | 计算域 |
In CFD, FEM, and other numerical methods, the area or volume within which calculations are performed and on the periphery of which the boundary conditions are specified. 在CFD、FEM和其他数值方法中，执行计算的区域或体积以及在其外围指定边界条件的区域或体积。 |
| Available resource | 可用资源 |
(total resource) (Unit J) The total annual energy theoretically available from a renewable-energy source, such as ocean waves, the wind, or the total incident solar energy. （总资源）（单位J）理论上可从可再生能源（例如海浪、风或总入射太阳能）获得的年度总能量。 |
| Toothed gearing | 齿轮传动 |
In principle, friction between circular discs in tangential contact could be used to transmit rotation and power between shafts, but the power level would be very limited and the velocity ratio affected by slip. To make the drive positive, gear wheels are used instead in which teeth extend above and below the diameters (the pitch-circle diameters) of discs in ideal rolling contact. The diagram shows the nomenclature for spur gears, the simplest type of gearing between parallel shafts, which are cylindrical in shape with straight teeth parallel to the axis of rotation. 原则上，切向接触的圆盘之间的摩擦可用于在轴之间传递旋转和动力，但动力水平非常有限，速比受滑动的影响。为了使驱动积极，使用齿轮代替，齿轮中的齿延伸到理想滚动接触的圆盘直径（节圆直径）的上方和下方。该图显示了直齿轮的名称，这是平行轴之间最简单的齿轮传动类型，其形状为圆柱形，直齿平行于旋转轴。 |
| Vacuum pump | 真空泵 |
A pump for exhausting air and non-condensable gases from a vessel to be maintained at sub-atmospheric pressure. The pirani and thermal-conductivity gauges are vacuum gauges used to measure the absolute pressure within a vacuum system (vacuum level), usually expressed in torr or Pa. 用于从容器中排出空气和不凝性气体以保持在亚大气压的泵。皮拉尼和热导率计是用于测量真空系统内绝对压力（真空水平）的真空计，通常用托或帕表示。 |
| Cone pulley | 锥轮 |
A stepped pulley having several diameters which, when linked by a laterallymoveable transmission belt to a corresponding pulley, gives a series of speed ratios. 具有多种直径的阶梯式皮带轮，当通过可横向移动的传动带连接到相应的皮带轮时，会产生一系列速比。 |
| Angle of torsion | 扭转角 |
(angle of twist) (Unit ° or rad) The angle relative to a chosen section, normal to the axis of twist, through which another part of a component rotates when subjected to a torque. （扭转角）（单位°或弧度）相对于选定截面的角度，垂直于扭转轴，部件的另一部分在受到扭矩时通过该角度旋转。 |
| Torque (T) (Unit N.m) | 扭矩（T）（单位：N.m） |
The twisting moment, product of force and wrench length, applied to a nut or bolt (for example). The twisting moment of a force or couple about an axis which results in torsion. 施加在螺母或螺栓（例如）上的扭矩，是力和扳手长度的乘积。力或力偶绕轴产生扭转的力矩。 |
| Pascal’s law | 帕斯卡定律 |
When there is a change in pressure at any point in a confined fluid at rest, there is an equal change at every other point in the fluid volume. 当处于静止状态的受限流体中任何一点的压力发生变化时，流体体积中的每一点的变化都相等。 |
| Biomedical engineering | 生物医学工程 |
The application of engineering principles and methodology to the medical field. Examples involving mechanical engineering include the design and construction of artificial limbs and hearts, heart-lung machines, prosthetic eyes, and orthopaedic implants such as hip joints and pins to stabilize fractured bones. 工程原理和方法在医学领域的应用。涉及机械工程的例子包括假肢和心脏、心肺机、假眼和骨科植入物（如髋关节和用于稳定骨折骨骼的销钉）的设计和建造。 |
| Critical cooling rate | 临界冷却速度 |
The rate of continuous cooling required to prevent undesirable transformation. For steel, it is the minimum rate at which austenite must be continuously cooled to suppress transformations above the Ms temperature. 防止不期望的转变所需的连续冷却速率。对于钢，它是奥氏体必须持续冷却以抑制Ms温度以上的转变的最小速率。 |
| Atmometer | 气压计 |
(atmidometer, evaporimeter) An instrument that measures the rate of evaporation of water from a surface into the atmosphere. （湿度计，蒸发计）测量水从表面蒸发到大气中的速率的仪器。 |
| Hardness | 硬度 |
A measure of the resistance of a material to surface indentation or abrasion; may be thought of as a function of the stress required to produce some specified type of surface deformation. There is no absolute scale for hardness; therefore, to express hardness quantitatively, each type of test has its own scale of arbitrarily defined hardness. Indentation hardness can be measured by Brinell hardness test, Rockwell hardness test, Vickers hardness test, Knoop hardness test, and the Scleroscope hardness test. The ability of a ductile material to resist permanent deformation. It is a measure of plastic flow properties determined principally by indentation testing, but scratch hardness and rebound hardness are also employed. hardness scales The different measures of hardness given by different tests, such as indentation pressure in the Brinell and in the Vickers hardness tests, and the different Rockwell hardness numbers. 测量材料对表面压痕或磨损的阻力；可以认为是产生某些特定类型的表面变形所需的应力的函数。硬度没有绝对刻度，因此为了定量表示硬度，每种类型的试验都有自己的任意定义硬度等级。压痕硬度可通过布氏硬度试验、洛氏硬度试验，维氏硬度试验和努氏硬度试验以及硬化镜硬度试验进行测量。延展性材料具有抵抗永久变形的能力，它是主要通过压痕测试确定的塑性流动性能的量度，也使用划痕硬度和回弹硬度。硬度标度不同试验给出的不同硬度测量值，如布氏硬度试验和维氏硬度试验中的压痕压力，以及不同的洛氏硬度值。 |
| Work ratio | 工作比 |
The ratio of the net work out to the actual work out for a thermodynamic cycle. 热力学循环的净功与实际功之比。 |
| Torque pack | 扭矩包 |
A geared wrench which multiplies input torque and provides a read-out of output torque. In effect, a combination of a Torque wrench and a Torque multiplier. 一种齿轮扳手，可增加输入扭矩并提供输出扭矩读数。实际上，它是扭矩扳手和扭矩倍增器的组合。 |
| Tyre | 轮胎 |
A flexible ring-shaped cover mounted on a wheel rim that supports the weight of a vehicle, such as a motor vehicle, aircraft, or bicycle, and transmits power and torque to a road surface. Some pneumatic tyres are inflated directly, others have a separate inner tube that is inflated. For certain applications, solid tyres are used. 车轮罩安装在轮辋上的柔性环形罩，用于支撑车辆（如机动车、飞机或自行车）的重量，并将动力和扭矩传递到路面。有些充气轮胎是直接充气的，有些轮胎有单独的内胎充气。对于某些应用，使用实心轮胎。 |
| Graham’s laws | 格雷厄姆定律 |
The laws stating that the rates of diffusion and effusion of a gas are inversely proportional to the square root of its density. 规定气体的扩散和渗出速率与其密度的平方根成反比的定律。 |
| Temper | 回火 |
(1) In heat treatment, reheating hardened steel or hardened cast iron to some temperature below the eutectoid temperature for the purpose of decreasing hardness and increasing toughness. The process also is sometimes applied to normalized steel. (2) In tool steels, temper is sometimes used, but inadvisedly, to denote the carbon content. (3) In nonferrous alloys and in some ferrous alloys (steels that cannot be hardened by heat treatment), the hardness and strength produced by mechanical or thermal treatment, or both, and characterized by a certain structure, mechanical properties, or reduction in area during cold working. （1）在热处理中，将硬化钢或硬化铸铁重新加热到共析温度以下的温度，以降低硬度和增加韧性。该工艺有时也适用于正火钢。（2）在工具钢中，有时使用回火来表示碳含量，但这是不恰当的。（3）在非铁合金和一些铁合金（不能通过热处理硬化的钢）中，通过机械或热处理或两者产生的硬度和强度，其特征是在冷加工过程中具有一定的结构、机械性能或面积减小。 |
| Superheating | 过热 |
Heating above the temperature at which an equilibrium phase transformation should occur without actually obtaining the transformation. 在不实际获得相变的情况下，加热到应发生平衡相变的温度以上。 |
| Bypass valve | 旁通阀 |
A valve that directs flow through a bypass. 引导流过旁路的阀门。 |
| Ball screw and nut | 滚珠丝杠和螺母 |
A nut and bolt assembly having semi-circular helical grooves, as opposed to threads, in which run ball bearings. On rotation of the nut, the balls move along the helix and carry the axial load. Balls reaching the end of the groove are recirculated back to the beginning. Such devices have low friction and very little backlash, and are used in some steering mechanisms. 一种螺母和螺栓组件，具有半圆形螺旋槽，与螺纹相反，在其中运行滚珠轴承。在螺母旋转时，滚珠沿螺旋线移动并承受轴向载荷。到达凹槽末端的滚珠被循环回起点。这种装置具有低摩擦和非常小的背隙，并且用于一些转向机构。 |
| Stud | 螺柱 |
A rod having thread on both ends. A headless threaded fastener, threaded on both ends, with an unthreaded body in the middle section, or threaded from end to end. Used with two nuts, or with one nut and a tapped hole. A plain cylindrical piece having a threaded portion of suitable length at each end or a continuous thread over the entire length. One end is screwed into a machine or workpiece after which a second part is placed over the stud and held in place by a nut. 两端都有螺纹的杆。无头螺纹紧固件，两端有螺纹，中间部分有无螺纹主体，或从一端到另一端有螺纹。与两个螺母或一个螺母和一个螺纹孔一起使用。一种普通的圆柱形部件，其两端具有适当长度的螺纹部分，或在整个长度上具有连续螺纹。一端拧入机器或工件，然后将第二部分放在螺柱上，并用螺母固定到位。 |
| ASME | ASME |
The American Society of Mechanical Engineers. 美国机械工程师学会。 |
| Starting torque (Unit N.m) | 起动扭矩（单位：N.m） |
The torque developed by a motor at zero rotational speed in order to initiate rotation of the applied load. 电机在零转速下产生的扭矩，以启动所施加负载的旋转。 |
| Biaxial stress | 双轴应力 |
Generalized loading of a body in a single plane with no loading normal to it. 物体在一个平面内的广义载荷，没有垂直于它的载荷。 |
| Positive-displacement compressor | 容积式压缩机 |
Any type of compressor, including piston and rotary-screw types, that delivers a fixed volume of gas at high pressure per unit time. A positive-displacement pump delivers a fixed volume of fluid, usually a liquid, per unit time. 任何类型的压缩机，包括活塞式和旋转螺杆式，在单位时间内以高压输送固定体积的气体。容积泵每单位时间输送固定体积的流体，通常为液体。 |
| Cyaniding | 氰化 |
A case-hardening process in which a ferrous material is heated above the lower transformation range in a molten salt containing cyanide to cause simultaneous absorption of carbon and nitrogen at the surface and, by diffusion, create a concentration gradient. Quench hardening completes the process. 一种表面硬化工艺，将含铁材料在含氰化物的熔融盐中加热至低于较低转变范围，使其表面同时吸收碳和氮，并通过扩散形成浓度梯度。淬火硬化完成该过程。 |
| Circlip | 卡簧 |
(snap ring) An external or internal retaining ring that locates parts of circular cross section in an axial direction. It consists of an incomplete ring, with holes on either side of the gap, that may be expanded by a plier-like tool to pass into a groove in a shaft or contracted to pass into a groove in a bore. （卡环）在轴向定位圆形横截面部分的外部或内部保持环。它由一个不完整的环组成，在间隙的任一侧都有孔，可以通过钳形工具将其扩展以进入轴中的凹槽或收缩以进入孔中的凹槽。 |
| Finishing washer | 光制垫圈 |
A washer designed for use with countersunk screws. Used to enhance appearance in some applications. 设计用于沉头螺钉的垫圈。在某些应用中用于增强外观。 |
| Ideal gas laws | 理想气体定律 |
The law relating pressure, temperature and volume of an ideal (perfect) gas pV = mRT, where R is the gas constant. The law implies that at constant temperature T, the product of pressure p and volume V is constant (Boyle’s law), and at constant pressure, the volume is proportional to the temperature (Charles’ law). 与理想（完美）气体的压力、温度和体积相关的定律pV=mRT，其中R是气体常数。该定律意味着在恒定温度T下，压力p和体积V的乘积是恒定的（波义耳定律），而在恒定压力下，体积与温度成正比（查尔斯定律）。 |
| Fretting corrosion | 微动腐蚀 |
(1) The accelerated deterioration at the interface between contacting surfaces as the result of corrosion and slight oscillatory movement between the two surfaces. (2) A form of fretting in which chemical reaction predominates. Fretting corrosion is often characterized by the removal of particles and subsequent formation of oxides, which are often abrasive and so increase the wear. Fretting corrosion can involve other chemical reaction products, which may not be abrasive. （1）由于两个表面之间的腐蚀和轻微振荡运动，接触表面之间的界面加速劣化。（2）一种以化学反应为主的微动磨损形式。微动腐蚀通常以颗粒的去除和随后形成的氧化物为特征，这些氧化物通常具有研磨性，因此会增加磨损。微动腐蚀可能涉及其他化学反应产物，这些化学反应产物可能不是磨料。 |
| Half hard | 半硬化回火 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength about mid-way between that of dead soft and full hard tempers. 非铁合金和某些铁合金的一种回火，其特点是抗拉强度介于完全软回火和完全硬回火之间。 |
| Union (union joint) | 活接头 |
A threaded pipe fitting that allows two pipes to be connected anddetached without the need for either to be rotated, and without damaging the pipe ends. 一种螺纹管件，允许连接和拆卸两个管道，而无需旋转任何一个管道，且不会损坏管道端部。 |
| Stress relieving | 应力消除 |
Heating to a suitable temperature, holding long enough to reduce residual stresses, and then cooling slowly enough to minimize the development of new residual stresses. 加热到合适的温度，保持足够长的时间以减少残余应力，然后缓慢冷却以尽量减少新残余应力的产生。 |
| Standard deviation (σ) | 标准偏差（σ） |
A statistical term used to quantify the Scatter in a set of data points. If the standard deviation is small, most of the data points are ‘‘nearly equal.’’ A large deviation means less agreement. The most usual measure of the dispersion of observed values or results expressed as the positive square root of the variance. The square root of variance, a measure of the spread of data about the mean value. 用于量化一组数据点中分散度的统计术语。如果标准偏差很小，则大多数数据点“几乎相等”大的偏差意味着更少的一致性。观测值或结果离散度的最常用度量，表示为方差的正平方根。方差的平方根，衡量平均值的数据分布。 |
| Artificial aging | 人工时效 |
Aging above room temperature. 在室温以上的时效。 |
| mechanical engineering | 机械工业 |
That branch of engineering concerned with energy conversion, stress analysis, vibration, dynamics, and kinematics, especially applied to design (machine design, mechanical-engineering design). 与能量转换、应力分析、振动、动力学和运动学有关的工程分支，尤其适用于设计（机器设计、机械工程设计）。 |
| High-tensile bolt | 高强度螺栓 |
(high-tension bolt) A bolt manufactured from an alloy steel that has a high tensile strength of about 1 GPa. （高压螺栓）由合金钢制成的螺栓，具有约1GPa的高抗拉强度。 |
| Shank | 螺杆 |
Portion of a bolt which lies under the head. 1. The stem of a tool, such as a broach, drill bit, reamer, or tap, which fits into a holder such as a chuck. 2. The stem of a rivet or the unthreaded part of a screw or bolt. 3. The shaft of a tool connecting the tip and the handle. 螺栓头部下方的部分。1.一种工具的柄部，如拉刀、钻头、铰刀或丝锥，可装入夹具（如卡盘）中。铆钉的杆或螺钉或螺栓的无螺纹部分。3.连接尖端和手柄的工具的轴。 |
| Stress raisers | 局部应力集中 |
Changes in contour or discontinuities in structure that cause local increases in stress. 导致局部应力增加的轮廓变化或结构不连续性变化。 |
| Drift pin | 冲头 |
A round tapered steel pin used to align rivet holes so that the rivet will pass through the holes easily. 用于对齐铆钉孔的圆形锥形钢销，以便铆钉轻松穿过孔。 |
| Tension testing | 张力测试 |
A method of determining the behavior of materials subjected to uniaxial loading, which tends to stretch the metal. A longitudinal specimen of known length and diameter is gripped at both ends and stretched at a slow, controlled rate until rupture occurs. Also known as tensile testing. 一种确定材料在单轴载荷下的行为的方法，这种载荷倾向于拉伸金属。将已知长度和直径的纵向试样夹持在两端，并以缓慢、受控的速率拉伸，直到发生断裂。也称为拉伸测试。 |
| Compression ratio | 压缩率 |
The volume of a combustion chamber with the piston at the top of its stroke as a proportion of the total volume of the cylinder with the piston at the bottom of its stroke. For a piston engine, if the swept volume is SW and the clearance volume is CL, the compression ratio is given by ( SW + CL)/CL, i.e. it is a volume ratio rather than a pressure ratio. 活塞位于其冲程顶部的燃烧室的容积与活塞位于其冲程底部的气缸总体积的比例。对于活塞发动机，如果扫气量为SW，间隙容积为CL，则压缩比由(SW+CL)/CL给出，即它是体积比而不是压力比。 |
| Air composition | 空气成分 |
The sea-level composition (in per cent by volume) of air at a temperature of 15°C and a pressure of 1 atm is mainly 78.084% nitrogen, 20.947% oxygen and 0.934% argon. The remaining 0.035% consists of carbon dioxide, neon, helium, methane, krypton, hydrogen, oxides of nitrogen, xenon, ozone, iodine, carbon monoxide, and ammonia. Different sources give slightly different figures for the composition. Not included are water vapour (typically 0.4%) and pollutants such as sulfur dioxide. 在15°C的温度和1个大气压的压力下，空气的海平面成分（体积百分比）主要是78.084%的氮气、20.947%的氧气和0.934%的氩气。剩余的0.035%由二氧化碳、氖、氦、甲烷、氪、氢、氮的氧化物、氙、臭氧、碘、一氧化碳和氨组成。不同的来源给出的组成略有不同。不包括水蒸气（通常为0.4%）和二氧化硫等污染物。 |
| Physical properties | 物理性质 |
Properties of a material the determination of which does not involve the deformation or destruction of the specimen—for example, density, electrical conductivity, coefficient of thermal expansion, magnetic permeability, and lattice parameter. Does not include chemical reactivity or the properties more appropriately regarded as mechanical properties. 不涉及试样变形或破坏的材料特性，例如密度、电导率、热膨胀系数、磁导率和晶格参数。不包括化学反应性或更适当地视为机械的性质。 |
| Design heating load (Unit kW) | 设计热负荷（单位kW） |
The heating requirements based on a specified number of heating degree days, or required to maintain a building or other enclosed space at a specified temperature for a given outside temperature. 基于指定的采暖度日数的加热要求，或在给定的外部温度下将建筑物或其他封闭空间保持在指定温度下所需的加热要求。 |
| Elastic interactions | 弹性相互作用 |
When a bolt is tightened it partially compresses the joint members ‘‘in its own neighborhood.’’ When nearby bolts are tightened later, they further compress the joint in this region. This allows the first bolt to relax a little (lose a little preload). Tightening bolts on the opposite side of the joint, however, might increase preload in some of the earlier bolts tightened on the near side. These shifts and changes in the elastic energy stored in individual bolts, during assembly, are called elastic interactions. 当螺栓拧紧时，它会“在其自身附近”部分压缩接头构件稍后拧紧附近的螺栓时，进一步压缩该区域的接头。这允许第一个螺栓稍微松弛（失去一点预载）。但拧紧接头另一侧的螺栓可能会增加早期在近侧拧紧的一些螺栓的预载。在装配过程中，储存在单个螺栓中的弹性能量的这些位移和变化称为弹性相互作用。 |
| Semi-rotary pump | 半回转泵 |
A form of self-priming pump, often hand-operated, suitable for pumping water and light oils such as diesel oil and petrol. As shown in the diagram, liquid is sucked into one side of the pump through flap valves and simultaneously ejected from the other side on one stroke. The sequence is reversed on each successive stroke. 一种自吸泵，通常是手动的，适用于泵送水和轻油，如柴油和汽油。液体通过翻板阀吸入泵的一侧，同时在一个冲程中从另一侧排出。在每个连续冲程上，顺序颠倒。 |
| Oldham coupling | 十字联轴节 |
(double-slider coupling) A device for connecting a pair of misaligned parallel shafts, on the end of each of which are flanges having diametral tenons (tongues) that engage with matching slots spaced at 90° in an intermediate disc. As the coupling rotates, the disc compensates for shaft offset by sliding along each tenon in turn. Low-friction surfaces are requisite and the disc is often made of a polymer. An alternative arrangement has the slots in the flanges and the tenons on the disc. （双滑块联轴器）一种连接一对未对准平行轴的装置，在每个平行轴的端部有法兰，法兰具有直径榫（舌），与中间盘中间隔90°的匹配槽接合。当联轴器旋转时，圆盘通过依次沿每个榫头滑动来补偿轴偏移。低摩擦表面是必需的，阀盘通常由聚合物制成。另一种布置方式是法兰上的槽和阀盘上的榫头。 |
| Screw | 螺钉 |
Threaded fastener designed to be used in a tapped or untapped (e.g., wood screw) hole, but not with a nut. A fastener with a screw thread cut or rolled into its cylindrical or conical shank, intended either to cut its own thread (as in a wood screw) or engage in a threaded hole. A self-tapping screw (sheet-metal screw, tapping screw) has a sufficiently hard thread that it cuts an internal thread in thin sheet or a component made of soft material when driven into a hole in the sheet or component. The screw head is the part of a screw used to apply torque to the screw. Common screw-head designs are circular in cross section with a diametral slot or cross, or hexagonal and recessed with a cross or hexagon. A screw thread is one or more continuous helical grooves of uniform section along either the exterior surface (male thread) or the interior surface (female thread) of a cylindrical or conical body. The three-dimensional shape that results when the thread cross section is rotated and axially advanced along an axis is called a helicoid, the angle that the thread makes when projected on to the axis being called the angle of inclination. Threads are employed in fasteners such as bolts, nuts, and screws; location and measuring instruments; in power drives; in some electrical fittings (Edison thread); and on the ends of crankshafts to suppress oil leakage (thrower thread). Parallel threads are formed on cylinders; tapered threads on cones, typically with a taper rate of 1:16. A screw with a righthanded thread appears to move away from the observer when turned clockwise. All standard screws, bolts and nuts have right-hand threads, but left-handed threads are sometimes employed. The axial distance between corresponding points on adjacent threads is called the screw pitch or screw rate and, for a single continuous helical groove (a single-start thread), is the same as the change in axial distance (the lead) between a nut and the head of a bolt during one revolution, the number of thread forms per mm then being the reciprocal of the pitch. For the same screw diameter, coarse threads have fewer threads per mm than fine threads. A multiple-start screw thread (usually coarse, see later) consists of two or more identical threads running simultaneously along its axis so as to provide greater bearing area and greater velocity ratio. The starts are separated by 180° (double start), 120° (triple start), 90° (quadruple start) etc., depending upon the number of threads. Thus, in double-start threads, the lead is twice the pitch; and so on. The axial distance between corresponding points on two adjacent threads in a multiple start thread is called the divided pitch. The position on a screw thread where there is equal distance between the flanks on the solid part of the thread and in the space between the threads is the pitch point, the associated diameter of which is termed the pitch diameter. The basic nomenclature for threads, some of which is common with that for toothed gearing, is shown in the diagrams. A helix formed or cut on a cylindrical surface which may advance along the axis to the right or left. The helix may be single or multiple. 一种螺纹紧固件，设计用于攻丝或未攻丝（如木螺钉）孔，但不与螺母配合使用。其螺纹被切割或卷成圆柱形或锥形柄，用于切割自身螺纹（如木螺钉）或嵌入螺纹孔。自攻螺钉（钣金螺钉、自攻螺钉）具有足够硬的螺纹，当打入薄板或部件中的孔时，它会在薄板或软材料部件中切割内螺纹。螺钉头是螺钉的一部分，用于向螺钉施加扭矩。常见的螺钉头设计为横截面为圆形，带有直径槽或十字，或为六边形，并带有十字或六边形凹槽。螺纹是沿圆柱形或锥形体的外表面（外螺纹）或内表面（内螺纹）具有均匀截面的一个或多个连续螺旋槽。当螺纹横截面旋转并沿轴轴向前进时产生的三维形状称为螺旋面，螺纹投影到轴上时形成的角度称为倾角。螺纹用于紧固件，如螺栓、螺母和螺钉；定位和测量仪器；在动力驱动中；在一些电气配件中（爱迪生螺纹）；并安装在曲轴端部，以抑制漏油（抛掷器螺纹）。在圆柱体上形成平行螺纹；圆锥上的锥形螺纹，通常具有1:16的锥形率。当顺时针旋转时，具有右手螺纹的螺钉似乎会远离观察者。所有标准螺钉、螺栓和螺母都有右手螺纹，但有时使用左手螺纹。相邻螺纹上对应点之间的轴向距离称为螺距或螺纹率，对于单个连续螺旋槽（单个起始螺纹），与螺母和螺栓头之间的轴向间距（导程）在一周内的变化相同，每mm的螺纹形式数为螺距的倒数。对于相同的螺钉直径，粗螺纹的每毫米螺纹数少于细螺纹。多头螺纹（通常为粗螺纹，见下文）由两个或多个沿其轴线同时延伸的相同螺纹组成，以提供更大的承载面积和更大的速比。根据螺纹的数量，起点之间的间隔为180°（双起点）、120°（三起点）、90°（四起点）等。因此，在双起始螺纹中，导程是螺距的两倍；多起点螺纹中两个相邻螺纹上对应点之间的轴向距离称为分割螺距。螺纹上的位置，即螺纹实体部分的侧面和螺纹之间的空间之间的距离相等，即节点，其相关直径称为节径。图中显示了螺纹的基本术语，其中一些与齿轮传动的基本术语相同。在圆柱面上形成或切割的螺旋线，可沿轴线向右或向左前进。螺旋可以是单个或多个。 |
| Atomizing humidifier | 雾化加湿器 |
A humidifier that functions by spraying fine droplets of water into an airstream. 一种加湿器，通过将细小的水滴喷射到气流中来发挥作用。 |
| Rotor | 转子 |
A part of a machine that rotates on a shaft (rotor shaft) about its own axis, such as the blade-carrying discs of a turbine, the blades of a helicopter, or the rotating parts of a Roots blower. 绕轴（转子轴）绕其自身轴线旋转的机器部件，如涡轮叶片、直升机叶片或罗茨鼓风机的旋转部件。 |
| Tensile stress (Unit Pa) | 拉应力（单位Pa） |
A stress that causes two parts of an elastic body, on either side of a typical stress plane, to pull apart. A stress that tends to stretch a component, or local region of a component, when under load. In simple tension it results from the applied axial load, but tensile stresses occur in bending, torsion and other forms of loading. 一种应力，使弹性体的两个部分在典型应力平面的任一侧分离。在负载下，倾向于拉伸部件或部件局部区域的应力。在简单拉伸中，它由施加的轴向载荷产生，但拉伸应力发生在弯曲、扭转和其他形式的载荷中。 |
| Linear (tensile or compressive) strain | 线性（拉伸或压缩）应变 |
The change per unit length due to force in an original linear dimension. An increase in length is considered positive. 由于原始线性尺寸中的力，每单位长度的变化。长度的增加被认为是正的。 |
| Hexagon nut | 六角螺母 |
A nut having six sides and shaped like a hexagon. 六边形的螺母。 |
| Strain-hardening exponent (n value) | 应变硬化指数（n值） |
The value n in the relationship σ = Kεn, where σ is the true stress, ε is the true strain, and K, the strength coefficient, is equal to the true stress at a true strain of 1.0. The strain hardening exponent is equal to the slope of the true stress/true strain curve up to maximum load, when plotted on log-log coordinates. The n-value relates to the ability of a sheet of material to be stretched in metalworking operations. The higher the n-value, the better the formability(stretchability). Also known as the strain-hardening coefficient. 关系式σ=Kεn中的值n，其中σ是真应力，ε是真应变，K是强度系数，等于真应变为1.0时的真应力。在对数坐标上绘制时，应变硬化指数等于真应力/真应变曲线的斜率，直到最大载荷。n值与一片材料在金属加工操作中拉伸的能力有关。n值越高，成形性（拉伸性）越好。也称为应变硬化系数。 |
| Shrink ring | 预紧环 |
A ring, which is expanded by heating, is placed around an assembly of parts, and then contracts upon cooling to hold the assembly in place. 通过加热膨胀的环被放置在零件组件周围，然后在冷却时收缩以将组件固定到位。 |
| Pressure recovery (Unit Pa) | 压力恢复（单位Pa） |
The progressive increase in static pressure for unseparated flow through a diverging nozzle or diffuser. 通过发散喷嘴或扩散器的未分离流的静压逐渐增加。 |
| Washer | 垫圈 |
An annular disc of metal, rubber, plastic, ceramic, etc., placed between two surfaces in contact either to spread the load (for example, between a surface and a tightened nut or a bolt head), to provide a seal, or to separate or align components. 由金属、橡胶、塑料、陶瓷等制成的环形圆盘，放置在两个接触面之间，以分散载荷（例如，在一个表面和拧紧的螺母或螺栓头之间），提供密封，或分离或对齐部件。 |
| Hot pressing | 热压 |
1. Sintering of metal or ceramic powder at high temperature. 2. Formation of components from fibre-reinforced composite material in which bonding is ensured through application of pressure and temperature, often against a mould to give the required shape. 1、金属或陶瓷粉末的高温烧结。2. 由纤维增强复合材料形成部件，其中通过施加压力和温度来确保粘合，通常靠在模具上以形成所需的形状。 |
| Crankshaft | 曲轴 |
The main shaft, of which the cranks are a part, of a reciprocating single-or multi-cylinder machine. Crankshafts may be built up in sections or forged as a single component. In an engine, the reciprocating motion of the pistons transmits power to the crankshaft and causes it to rotate, whereas in a pump the crankshaft is driven and its rotation causes the pistons to reciprocate. 曲柄是往复式单缸或多缸机器主轴的一部分。曲轴可以分段组装或作为单个部件锻造。在发动机中，活塞的往复运动将动力传递给曲轴并使其旋转，而在泵中，曲轴被驱动，其旋转使活塞往复运动。 |
| Working load (Unit N) | 工作负荷（单位：N） |
The tension in a bolt in use; tension produced by a combination of Residual preload and a portion (usually) of any External load. The Joint diagram is usually used to predict the approximate working load a fastener will see in service. The load under which a component or structure is designed to operate under normal conditions. 螺栓在使用中的张力；残余预载荷和部分（通常）任何外部载荷的组合产生的张力。连接图通常用于预测紧固件在使用中的近似工作载荷。部件或结构设计为在正常条件下运行的荷载。 |
| Centi (c) | 厘（c） |
An SI unit prefix indicating a multiplier of 0.01; thus centimetre is a unit of length equal to one one-hundredth of a metre or 10 mm. 表示乘数0.01的SI单位前缀；因此厘米是长度单位，等于一米的百分之一或10毫米。 |
| Spring clip | 弹簧夹 |
A clip made of a material such as spring steel which grips an inserted part. 由弹簧钢等材料制成的夹子，用于夹住插入的零件。 |
| Wallner lines | Wallner线 |
A distinct pattern of intersecting sets of parallel lines, usually producing a set of V-shaped lines, sometimes observed when viewing brittle fracture surfaces at high magnification in an electron microscope. Wallner lines are attributed to interaction between a shock wave and a brittle crack front propagating at high velocity. Sometimes Wallner lines are misinterpreted as fatigue striations. 一组相交的平行线的独特图案，通常产生一组V形线，有时在电子显微镜下高倍观察脆性断裂表面时观察到。Wallner线归因于高速传播的冲击波和脆性裂纹前沿之间的相互作用。有时Wallner线被误解为疲劳条纹。 |
| Cooling coil | 冷却盘管 |
A simple heat exchanger consisting of a coiled tube, typically of copper or stainless steel, through which is circulated a coolant such as a refrigerant, chilled water, or water mixed with ethylene glycol. Applications include air conditioning, process cooling, and refrigeration. 一种简单的热交换器，由通常由铜或不锈钢制成的盘管组成，冷却剂如制冷剂、冷冻水或与乙二醇混合的水通过盘管循环。应用包括空调、工艺冷却和制冷。 |
| Tribology | 摩擦学 |
The science and technology concerned with interacting surfaces in relative motion. 与相对运动中相互作用的表面有关的科学和技术。 |
| Celsius temperature scale | 摄氏温标 |
(centigrade temperature scale) A relative, non-SI, temperature scale now defined in terms of the Kelvin absolute temperature scale as °C = K − 273.15, where °C is the symbol for degrees Celsius. The scale was previously called the centigrade scale, with two fixed points: the melting point of ice (the ice point) as 0°C, and the boiling point of water (the steam point) as 100°C. （摄氏度温度标度）现在以开尔文绝对温度标度定义的相对非国际温度标度为°C=K-273.15，其中°C是摄氏度的符号。该刻度以前称为摄氏度刻度，有两个固定点：冰的熔点（冰点）为0°C，水的沸点（蒸汽点）为100°C。 |
| Horsepower | 马力 |
Unit indicating the rate at which work is done. The electrical equivalent of one horsepower is 746 watts. 单位表示完成工作的速率。一马力的电当量为746瓦。 |
| Scoring | 划痕 |
In tribology, a severe form of wear characterized by the formation of extensive grooves and scratches in the direction of sliding. 在摩擦学中，一种严重的磨损形式，其特征是在滑动方向上形成大面积的凹槽和划痕。 |
| B-basis | B-基础 |
Mechanical property value above which at least 90% of the population of values is expected to fall, with a confidence of 95%. 机械性能值超过该值时，至少90%的值预计会下降，置信度为95%。 |
| Closed-die forging | 闭模锻造 |
The forming of a workpiece by compression within a pair of dies having the female form of the component to be manufactured (closed dies), superfluous metal being expelled as flash where the dies meet. 在一对具有待制造部件的阴模的模具（闭模）内通过压缩形成工件，多余的金属在模具相遇处作为飞边排出。 |
| Sound pressure (Unit μPa) | 声压（单位：μPa） |
The instantaneous deviation of pressure from the ambient pressure caused by the passage of a sound wave, which can be measured by a microphone in air and a hydrophone in water. 声波传播引起的压力与环境压力的瞬时偏差，可通过空气中的麦克风和水中的水听器测量。 |
| Bearing failure | 轴承故障 |
A failure that occurs in a riveted or bolted joint when the transverse load divided by the bearing area results in a stress that leads to permanent plastic deformation. 当横向载荷除以承载面积产生导致永久塑性变形的应力时，铆接或螺栓连接中发生的失效。 |
| Standard fit | 标准匹配 |
The fit of a component machined or otherwise manufactured to standardized clearances and tolerances. 根据标准间隙和公差加工或以其他方式制造的部件的配合。 |
| Microindentation hardness test | 显微压痕硬度测试 |
Hardness test using a calibrated machine to force a diamond indenter of specific geometry, under a test load of 1 to 1000 gramforce, into the surface of the test material and to measure the diagonal or diagonals of the indentation optically. 使用校准机器进行硬度试验，以在1至1000克力的试验载荷下，将特定几何形状的金刚石压头压入试验材料表面，并光学测量压痕的对角线。 |
| Transverse strain | 横向应变 |
Linear strain in a plane perpendicular to the loading axis of a specimen. 垂直于试样加载轴的平面内的线性应变。 |
| Quarter hard | （1/4H）低硬（回火） |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength aboutmidway between that of dead soft and half hard tempers. 非铁合金和某些铁合金的一种回火，其特点是抗拉强度介于软态和半硬态之间。 |
| Thermal fatigue | 热疲劳 |
Fatigue resulting from the presence of temperature gradients that vary with time in such a manner as to produce cyclic stresses in a structure. 由于温度梯度的存在而产生的疲劳，温度梯度随时间变化，从而在结构中产生循环应力。 |
| Distortion | 扭曲 |
Any deviation from an original size, shape, or contour that occurs because of the application of stress or the release of residual stress. 由于施加应力或释放残余应力而发生的与原始尺寸、形状或轮廓的任何偏差。 |
| Thermal shock | 热冲击 |
The development of a steep temperature gradient and accompanying high stresses within a structure. 在结构内形成陡峭的温度梯度和伴随的高应力。 |
| Actual power | 实际功率 |
(actual horsepower) (Unit W or hp) The power delivered at the output shaft of an engine, before subsequent transmission through a gearbox etc. （实际马力）（单位W或hp）在随后通过变速箱等传输之前，在发动机输出轴上传递的功率。 |
| Starting valve (regulator) | 起动阀（调节器） |
A valve which admits steam from the boiler to the cylinder(s) of a steam engine. 将蒸汽从锅炉送入蒸汽机汽缸的阀门。 |
| Major diameter | 螺纹大径 |
On a straight thread, the diameter of the imaginary cylinder that just touches the crest of an external thread or the root of an internal thread. 在直螺纹上，仅接触外螺纹顶部或内螺纹根部的假想圆柱体的直径。 |
| Microhardness | 显微硬度 |
The hardness of a material as determined by forcing an indenter such as a Vickers or Knoop indenter into the surface of a material under very light load; usually, the indentations are so small that they must be measured with a microscope. Capable of determining hardnesses of different microconstituents within a structure, or of measuring steep hardness gradients such as those encountered in case hardening. 通过在非常轻的载荷下将压头（如维氏或努氏压头）压入材料表面来确定的材料硬度；通常压痕很小，必须用显微镜测量。能够确定结构内不同微组分的硬度，或测量陡峭的硬度梯度，如表面硬化中遇到的硬度梯度。 |
| Granular fracture | 粒状断裂 |
A type of irregular surface produced when metal is broken that is characterized by a rough, grainlike appearance, rather than a smooth or fibrous one. It can be subclassified as transgranular or intergranular. 金属破碎时产生的一种不规则表面，其特征是粗糙的颗粒状外观，而不是光滑或纤维状的外观。它可以细分为穿晶或晶间。 |
| Alloying element | 合金元素 |
Component added deliberately with the aim of improving the properties of an alloy. Alloying elements can affect the existence range of equilibrium phases present in an unalloyed material, or lead to the occurrence of new phases, or both. In addition, alloying elements strongly affect the kinetics of phase transformations and thus the microstructure formation in alloyed materials. 为改善合金性能而有意添加的成分。合金元素可以影响非合金材料中存在的平衡相的存在范围，或导致新相的出现，或两者兼而有之。此外，合金元素强烈影响相变动力学，从而影响合金材料的微观结构形成。 |
| Compressible flow | 可压缩流动 |
A gas flow in which the Mach number M is sufficiently high for the gas density to change significantly. For air, this is when M > 0.3. 马赫数M高到足以使气体密度发生显着变化的气流。对于空气，这是当M>0.3时。 |
| Compression pressure (Unit Pa) | 压缩压力（单位Pa） |
The pressure produced in a cylinder of a piston engine by compression of air in the absence of fuel. 在没有燃料的情况下通过压缩空气在活塞发动机的气缸中产生的压力。 |
| Laser hardening | 激光硬化 |
A surface-hardening process which uses a laser to quickly heat a surface. Heat conduction into the interior of the part will quickly cool the surface, leaving a shallow martensitic layer. Hardening of steel by a moving CO2 or Nd:YAG laser beam focussed down to a few mm in diameter. A point in the surface of an object is rapidly heated into the austenite range and then rapidly cooled to form tempered martensite. 一种使用激光快速加热表面的表面硬化工艺。进入零件内部的热传导将快速冷却表面，留下浅马氏体层。通过移动CO2或Nd:YAG激光束使钢硬化，激光束聚焦至直径几毫米。物体表面的一点迅速加热到奥氏体范围，然后迅速冷却，形成回火马氏体。 |
| Flame straightening | 火焰矫直 |
Correcting distortion in metal structures by localized heating with a gas flame. 通过使用气体火焰进行局部加热来纠正金属结构的变形。 |
| Cavitation-resistance inducer | 抗气蚀诱导剂 |
An axial-flow pump used upstream of a main pump in order to prevent cavitation in the latter by increasing the inlet head. 在主泵上游使用的轴流泵，通过增加进口压头防止主泵出现气穴。 |
| True strain | 真应变 |
(1) The ratio of the change in dimension, resulting from a given load increment, to the magnitude of the dimension immediately prior to applying the load increment. (2) In a body subjected to axial force, the natural logarithm of the ratio of the gage length at the moment of observation to the original gage length. Also known as natural strain. Compare with engineering strain. （1）给定载荷增量导致的尺寸变化与施加载荷增量之前尺寸大小的比率。（2）在承受轴向力的物体中，观察时刻标距与原始标距之比的自然对数。也称为自然应变。与工程应变相比。 |
| Turbomachine | 涡轮机械 |
(rotodynamic machine) A machine in which there is a transfer of energy between a continuous stream of fluid and a component, called a rotor, rotating about a fixed axis. Fans and turbines (gas, hydraulic, steam, or wind) are turbomachines in which energy is transferred to the rotor, causing it to rotate. Pumps and compressors are turbomachines in which energy is transferred from the externally driven rotor to the fluid. （旋转动力机器）在连续的流体流和绕固定轴旋转的部件（称为转子）之间进行能量传递的机器。风扇和涡轮机（燃气、液压、蒸汽或风力）是涡轮机械，其中能量传递到转子，使其旋转。泵和压缩机是涡轮机械，其中能量从外部驱动的转子传递到流体。 |
| Total elongation | 总伸长率 |
A total amount of permanent extension of a test piece broken in a tensile test. 拉伸试验中断裂试样的永久延伸总量。 |
| Thermoelectric junction | 热电结 |
A welded, soldered, or twisted connection between the ends of two wires of dissimilar metals, as in a thermocouple. 两根不同金属线的末端之间的焊接、锡焊或绞合连接，如热电偶。 |
| Butterfly valve | 蝶阀 |
A valve in which a disc rotates on a shaft at right angles to the axis of a pipe to regulate flow. When open, the disc is edge-on to the flow and offers limited resistance. When closed, the disc is pressed against a seat in the valve body. 阀瓣在与管道轴线成直角的轴上旋转以调节流量的阀门。当打开时，圆盘与水流边缘并提供有限的阻力。关闭时，阀瓣被压在阀体内的阀座上。 |
| Stretch ratio (extension ratio, λ) | 拉伸比（拉伸比，λ） |
A measure, used for highly-extensible materials such as rubber, of the extensional or normal strain of a component subjected to tension and defined as the ratio of the final length l, for a given load, to the initial or gauge length l0, where the coordinate axes are those of principal strain. It is related to the engineering strain e by λ = 1 + e. 用于高度可延展材料（如橡胶）的一种测量方法，用于测量受拉构件的拉伸或法向应变，定义为给定载荷下的最终长度l与初始或标距长度l0之比，其中坐标轴为主应变轴。它与工程应变e的关系为λ=1+e。 |
| Strain-age embrittlement | 应变时效脆化 |
A loss in ductility accompanied by an increase in hardness and strength that occurs when low-carbon steel (especially rimmed or capped steel) is aged following plastic deformation. The degree of embrittlement is a function of aging time and temperature, occurring in a matter of minutes at about 200°C (400 °F), but requiring a few hours to a year at room temperature. 塑性变形后低碳钢（尤其是边缘钢或封顶钢）时效时发生的延展性损失，伴随着硬度和强度的增加。脆化程度是老化时间和温度的函数，在大约200°C（400°F）的温度下，在几分钟内发生，但在室温下需要几小时到一年。 |
| Absorption hygrometer | 吸收式湿度计 |
An instrument that determines the content of water vapour in the atmosphere by it being absorbed into a hygroscopic medium. 通过吸收到吸湿介质中来确定大气中水蒸气含量的仪器。 |
| Finish annealing | 精制退火 |
A subcritical annealing treatment applied to cold-worked low- or medium-carbon steel. Finish annealing, which is a compromise treatment, lowers residual stresses, thereby minimizing the risk of distortion in machining while retaining most of the benefits to machinability contributed by cold working. Compare with final annealing. 适用于冷加工低碳钢或中碳钢的亚临界退火处理。与最终退火相比，精加工退火是一种折衷处理，可降低残余应力，从而最大限度地降低加工中的变形风险，同时保留冷加工对可加工性的大部分好处。 |
| Tow | 拖拉 |
1. To cause a vehicle to move by pulling with a rope, chain, bar, etc. 2. A bundle of fibres employed in reinforcement. 1.用绳子、链条、钢筋等拉动车辆移动。2.用于加固的纤维束。 |
| Hypereutectoid alloy | 过共析合金 |
In an alloy system exhibiting a eutectoid, any alloy whose composition has an excess of alloying element compared with the eutectoid composition, and whose equilibrium microstructure contains some eutectoid structure. 在呈现共晶的合金系统中，合金成分比共晶成分多的任何合金，其平衡微观结构包含一些共晶结构。 |
| Vacuum carburizing | 真空渗碳 |
A high-temperature gas carburizing process using furnace pressures between 7 and 55 kPa during the carburizing portion of the cycle. 在循环的渗碳部分期间使用7至55kPa之间的炉压的高温气体渗碳工艺。 |
| Impact wrench | 冲击扳手 |
An air- or electric-powered wrench in which multiple blows from tiny hammers are used to produce output torque to tighten fasteners. A pneumatically-or electrically-powered socket wrench used to tighten or loosen nuts through the application of torque in a rapid series of impulses. 一种气动或电动扳手，使用小锤子多次敲击来产生输出扭矩以拧紧紧固件，用于通过在一系列快速脉冲中施加扭矩来拧紧或松开螺母。 |
| Stress area | 应力面积 |
The effective cross-sectional area of the threaded section of a fastener. Used to compute average stress levels in that section. Based on the mean of pitch and minor diameters. 紧固件螺纹部分的有效横截面积。用于计算该截面中的平均应力水平。基于节距和小直径的平均值。 |
| Temper color | 回火颜色 |
A thin, tightly adhering oxide skin that forms when steel is tempered at a low temperature, or for a short time, in air or a mildly oxidizing atmosphere. The color, which ranges from straw to blue depending on the thickness of the oxide skin, varies with both tempering time and temperature. 一种薄的、紧密粘附的氧化皮，当钢在低温或短时间内在空气或轻度氧化气氛中回火时形成。颜色范围从稻草色到蓝色，取决于氧化皮的厚度，随回火时间和温度而变化。 |
| Salt-velocity meter | 盐速计 |
A volume flow meter based on detecting the transit time for a small quantity of salt or radioactive isotope in a flow by measuring electrical conductivity or radiation level. 一种体积流量计，通过测量电导率或辐射水平来检测流量中少量盐或放射性同位素的渡越时间。 |
| Axial load (Unit N) | 轴向载荷（单位N） |
In general, a tensile or compressive load directed along the axis of a component. Strictly the load should pass through the centroid of the cross section to avoid inducing bending moments and be perpendicular to the plane of the section. 通常，沿部件的轴定向的拉伸或压缩载荷。严格来说，载荷应通过横截面的质心以避免产生弯矩并垂直于横截面。 |
| Bimetallic strip | 双金属片 |
A strip formed by welding, riveting or brazing together two metals having different coefficients of expansion, which causes the strip to curl when its temperature changes. Typical combinations are steel and copper or steel and brass. 将两种膨胀系数不同的金属焊接、铆接或钎焊在一起形成的带材，当温度变化时，带材会卷曲。典型的组合是钢和铜或钢和黄铜。 |
| Compressor | 压缩机 |
A turbomachine, of either axial or radial type, that increases the pressure of a gas or vapour. 一种增加气体或蒸汽压力的轴向或径向涡轮机。 |
| Compression spring | 压缩弹簧 |
A spring that resists compression forces, usually in the form of a helix with separated coils (giving a linear axial stiffness) or a cone with separated coils (giving a non-linear axial stiffness). 一种抵抗压缩力的弹簧，通常采用带有分离线圈的螺旋形式（提供线性轴向刚度）或带有分离线圈的锥形（提供非线性轴向刚度）。 |
| Kilo (k) | 千（k） |
An SI unit prefix indicating a multiplier of 103; thus kilometre (km) is a unit of length equal to one thousand metres. 表示乘法器103的SI单位前缀；1千米是长度单位，等于1000米。 |
| Transition temperature (Unit K) | 转变温度（单位K） |
(1) An arbitrarily defined temperature that lies within the temperature range in which metal fracture characteristics (as usually determined by tests of notched specimens) change rapidly, such as from primarily fibrous (shear)to primarily crystalline (cleavage) fracture. (2) Sometimes used to denote an arbitrarily defined temperature within a range in which the ductility changes rapidly with temperature. (transition point) 1. The temperature at which the mechanism of fracture in metal alloys having a face-centred cubic crystal structure changes from ductile void growth to brittle cleavage. 2. The temperature at which a material changes from one crystal state to another. （1） 任意定义的温度，位于金属断裂特性（通常通过缺口试样的试验确定）快速变化的温度范围内，如从主要纤维（剪切）断裂到主要结晶（解理）断裂。（2） 有时用于表示延性随温度快速变化的范围内的任意定义的温度。（转变点）1.具有面心立方晶体结构的金属合金的断裂机制从韧性孔洞生长转变为脆性解理的温度。2.材料从一种晶体状态转变为另一种晶体的温度。 |
| Zero initial conditions | 零初始条件 |
The assumption normally made in control engineering that up to a start time defined as t = 0, all variables have zero value. 在控制工程中通常作出的假设，即在定义为t=0的开始时间内，所有变量均为零值。 |
| Temperature (Unit K or °C) | 温度（单位K或°C） |
A quantitative measure of the molecular kinetic energy of a substance and so how hot or cold it is. 物质分子动能的定量量度，以及它的冷热程度。 |
| Hardenability | 淬透性 |
Defined as the ability of a ferrous material to acquire hardness after austenitization and quenching. The relative ability of a ferrous alloy to form martensite when quenched from a temperature above the upper critical temperature. Hardenability is commonly measured as the distance below a quenched surface where the metal exhibits a specific hardness (50 HRC, for example) or a specific percentage of martensite in the microstructure. 定义为黑色金属材料在奥氏体化和淬火后获得硬度的能力。铁合金从高于上临界温度的温度淬火时形成马氏体的相对能力。淬透性通常以淬火表面下方的距离来测量，金属在淬火表面处表现出特定硬度（例如50HRC）或微观结构中马氏体的特定百分比。 |
| Lock-nut pipe thread | 锁紧螺母管螺纹 |
The lock-nut pipe thread is a straight thread of the largest diameter which can be cut on a pipe. Its form is identical with that of the American or Briggs standard taper pipe thread. In general, “Go” gages only are required. These consist of a straight-threaded plug representing the minimum female lock-nut thread, and a straight-threaded ring representing the maximum male lock-nut thread. This thread is used only to hold parts together, or to retain a collar on the pipe. It is never used where a tight threaded joint is required. 锁紧螺母管螺纹是最大直径的直螺纹，可在管道上切割。其形式与美国或布里格斯标准锥管螺纹相同。一般情况下，只需要通规。它们由一个表示最小内螺纹锁紧螺母螺纹的直螺纹塞和一个表示最大外螺纹锁紧螺帽螺纹的直形螺纹环组成。该螺纹仅用于将零件固定在一起，或用于将轴环固定在管道上。切勿使用于需要紧密螺纹接头的情况下。 |
| Mass flow meter | 质量流量计 |
An instrument, such as a Coriolis flow meter, which measures the mass flow rate of a fluid flowing through a pipe or other duct, rather than its volume flow rate. 一种仪器，例如科里奥利流量计，一种测量流经管道或其他管道的流体的质量流率而不是其体积流率的仪器。 |
| Cold die quenching | 冷模淬火 |
A quench utilizing cold, flat, or shaped dies to extract heat from a part. Cold die quenching is slow, expensive, and is limited to smaller parts with large surface areas. 利用冷、平或成型模具从零件中提取热量的淬火。冷模淬火速度慢、成本高，并且仅限于表面积较大的较小零件。 |
| Strength (Unit Pa) | 强度（单位Pa） |
The maximum stress, in tension, compression, shear, or combinations thereof, that may be monotonically applied to a material, component, or structure before failure (defined as fracture, yielding, buckling, etc. as appropriate). 在破坏前（视情况定义为断裂、屈服、屈曲等），材料、部件或结构在拉伸、压缩、剪切或其组合中可能单调施加的最大应力。 |
| Blue brittleness | 蓝色脆性 |
Anomalous loss of ductility when quenched steels are tempered in the range 250–350°C (temperatures that produce blue tints on the surface of components). Brittleness exhibited by some steels after being heated to some temperature within the range of about 205 to 370 °C (400 to 700 °F), particularly if the steel is worked at the elevated temperature. Killed steels are virtually free of this kind of brittleness. 当淬火钢在250–350°C范围内回火（在部件表面产生蓝色色调的温度）时，延展性异常损失。某些钢在加热到约205至370°C（400至700°F）范围内的某个温度后表现出脆性，特别是在高温下加工钢时。镇静钢几乎没有这种脆性。 |
| Joule | 焦耳 |
The SI unit of energy. One joule is the work done by a force of one newton acting over a distance of one metre. The symbol is J, where 1 J = 1 N m. 国际单位制能量单位。一焦耳是一牛顿的力在一米的距离上所做的功。符号为J，其中1j=1m。 |
| Plastic deformation | 塑性变形 |
The permanent (inelastic) distortion of a material under applied stress that strains the material beyond its elastic limit. 材料在施加应力下的永久（非弹性）变形，使材料应变超过其弹性极限。 |
| Nanotechnology | 纳米技术 |
The science and engineering of materials that have been structured on length scales of 1–100 nm, resulting in modified physical properties owing to changes in the ratio of surface area to volume (atoms on surfaces having different symmetry from those in the bulk) and because many of the fundamental physical processes that underpin the properties of materials have a characteristic length scale of a few nm, so that alteration of microstructure at the nm level alters the bulk properties. 材料科学与工程，其结构长度为1-100nm，由于表面积与体积之比的变化（表面上的原子与体中的原子具有不同的对称性），并且支撑材料性质的许多基本物理过程具有几纳米的特征长度尺度，因此改变纳米级微观结构会改变体性质。 |
| Wave spring | 波形弹簧 |
A type of compression spring, similar to a coil spring, but made of strip shaped into waves around the circumference. 一种压缩弹簧，类似于螺旋弹簧，但由沿圆周成波浪形的条状物制成。 |
| Springback | 回弹 |
The extent to which metal tends to return to its original shape or contour after undergoing a forming operation. 金属在经历成形操作后趋于恢复其原始形状或轮廓的程度。 |
| Barrier protection | 屏障保护 |
The coating on a fastener is said to provide barrier protection if it merely isolates the fastener from the environment. Paint, for example, provides barrier protection. 如果仅将紧固件与环境隔离，则据说紧固件上的涂层可提供屏障保护。例如，油漆提供屏障保护。 |
| Cohesive strength | 内聚强度 |
(Unit Pa) A theoretical fracture strength for solids based on interatomic forces, approximately equal to E/10 where E is Young’s modulus. （单位Pa）基于原子间力的固体理论断裂强度，大约等于E/10，其中E是杨氏模量。 |
| Cleavage | 分裂 |
The tendency of a material to cleave or split along definite crystallographic planes. 材料沿特定晶面劈裂或分裂的趋势。 |
| Induction heating | 感应加热 |
Heating by combined electrical resistance and hysteresis losses induced by subjecting a metal to the varying magnetic field surrounding a coil carrying alternating current. 通过将金属置于承载交流电的线圈周围的变化磁场中而引起的电阻和磁滞损耗的组合加热。 |
| Hot-wire analyzer | 热电阻丝型分析仪 |
An electrical atmosphere analysis device that is based on the fact that the electrical resistivity of steel is a linear function of carbon content over a range from 0.05% C to saturation. The device measures the carbon potential of furnace atmospheres (typically). This term is not to be confused with the hot-wire test which measures heat extraction rates. 一种基于以下事实的电气氛分析设备：钢的电阻率是从0.05%C到饱和范围内的碳含量的线性函数。该设备测量炉内气氛的碳势（通常）。不要将此术语与测量热提取率的热线测试相混淆。 |
| Cylinder head | 气缸盖 |
The machined casting, typically of aluminium alloy or cast iron, that fits above the cylinder block of a piston engine and closes off the cylinders. It normally includes part of the combustion chambers and holes for the valves and spark plugs. 活塞式发动机缸体上方的机械铸件，通常由铝合金或铸铁制成，用于封闭气缸。它通常包括燃烧室的一部分以及阀门和火花塞的孔。 |
| Velocity defect (Unit m/s) | 速度亏损（单位：m/s） |
In a viscous flow, such as a boundary layer or wake, the reduction in velocity, due to friction, compared with that of the free stream. 在粘性流中，如边界层或尾迹，由于摩擦，与自由流相比，速度降低。 |
| Maximum allowable operating pressure (Unit Pa) | 最大允许使用压力（单位Pa） |
The highest pressure at which any pressure system may be operated, usually 10 to 20% below the maximum allowable working pressure. 任何压力系统可运行的最高压力，通常比最大允许工作压力低10%至20%。 |
| Stretch-bending test | 拉伸弯曲试验 |
A simulative test for sheet metal formability in which a strip of sheet metal is clamped at its ends in lock beads and deformed in the center by a punch. Test conditions are chosen so that fracture occurs in the region of punch contact. 金属板成形性的模拟试验，其中金属板条在其端部夹紧在锁珠中，并通过冲头在中心变形。选择试验条件，以便在冲头接触区域发生断裂。 |
| Surface treatment | 表面处理 |
Any process, including chemical, electrochemical, mechanical, and thermal, designed to protect a surface against corrosion and wear or to alter its mechanical properties. 任何旨在保护表面免受腐蚀和磨损或改变其机械性能的工艺，包括化学、电化学、机械和热处理。 |
| Acoustics | 声学 |
The science and engineering of sound; its production, propagation, control, interaction with materials, etc. 声音科学与工程；它的产生、传播、控制、与材料的相互作用等。 |
| Waist | 腰部 |
The joint in a robot corresponding to the human waist, i.e. providing rotation about a vertical axis. In an articulated robot, the first joint mounted at the base frame. 机器人中的关节对应于人的腰部，即提供绕垂直轴的旋转。在关节式机器人中，第一个关节安装在基架上。 |
| Flexural strength | 抗弯强度 |
The maximum stress in the outer fiber at the moment of crack or break. 断裂或断裂时刻外层纤维的最大应力。 |
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