| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Plane strain | 平面应变 |
The stress condition in linear-elastic fracture mechanics in which there is zero strain in a direction normal to both the axis of applied tensile stress and the direction of crack growth (i.e., parallel to the crack front); most nearly achieved in loading thick plates along a direction parallel to the plate surface. Under plane-strain conditions, the plane of fracture instability is normal to the axis of the principal tensile stress. 线弹性断裂力学中的应力条件，其中在垂直于施加拉应力轴和裂纹扩展方向（即平行于裂纹前沿）的方向上存在零应变；最接近于沿平行于板表面的方向加载厚板。在平面应变条件下，断裂失稳平面垂直于主拉应力轴。 |
| Diffusion coating | 扩散涂层 |
Coating on metal for corrosion- and/or oxidation-resistance. Coatings are produced by heating a metal in contact with an alloy in powder, liquid, or gaseous form at elevated temperature such that atoms of the coating diffuse into the substrate. Examples include chromium, aluminium, or silicon on substrates such as nickel-based superalloys, steels, and refractory metals. 金属上的防腐和/或抗氧化涂层。涂层是通过在高温下加热与粉末、液体或气体形式的合金接触的金属，从而使涂层的原子扩散到基体中而产生的。实例包括基底上的铬、铝或硅，如镍基高温合金、钢和耐火金属。 |
| Plowing | 犁 |
In tribology, the formation of grooves by plastic deformation of the softer of two surfaces in relative motion. 在摩擦学中，通过相对运动的两个表面中较软的表面的塑性变形形成凹槽。 |
| 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。 |
| Compressed liquid | 压缩液体 |
A liquid subjected to a pressure greater than the saturation pressure corresponding to its temperature. 承受大于与其温度对应的饱和压力的压力的液体。 |
| Subcritical annealing | 不完全退火 |
A process anneal performed on ferrous alloys at a temperature below Ac1. 在低于Ac1的温度下对铁合金进行的工艺退火。 |
| Diffusion | 扩散 |
(1) Spreading of a constituent in a gas, liquid, or solid, tending to make the composition of all parts uniform. (2) The spontaneous movement of atoms or molecules to new sites within a material. （1） 一种成分在气体、液体或固体中的扩散，趋于使所有部分的成分均匀。（2） 原子或分子自发运动到材料内的新位置。 |
| Scale height (Unit m) | 刻度高度（单位：m） |
The altitude H at which the atmospheric pressure has decreased to a certain fraction of its value at sea level B. It depends on the model adopted for the atmosphere: for an isothermal atmosphere, the pressure decreases exponentially with altitude. If H is taken as the altitude at which the pressure has fallen to B/e, then H = RT/g where R is the gas constant for air, T is the absolute temperature T, and g is the acceleration due to gravity. 大气压力降低到其在海平面B处数值的某一部分的高度H。它取决于大气采用的模型：对于等温大气，压力随高度呈指数下降。如果取H作为压力下降到B/e的高度，则H=RT/g，其中R是空气的气体常数，T是绝对温度T，g是重力引起的加速度。 |
| Torque reaction (Unit N.m) | 扭矩反作用力（单位：N.m） |
The torque needed to counteract an applied torque. For example, in a helicopter with a single main rotor, the tendency of the fuselage to rotate in the opposite direction to the rotor. 抵消施加扭矩所需的扭矩。例如，在具有单个主旋翼的直升机中，机身沿与旋翼相反的方向旋转的趋势。 |
| Shear strength | 抗剪强度 |
The maximum shear stress that a material is capable of sustaining. Shear strength is calculated from the maximum load during a shear or torsion test and is based on the original dimensions of the cross section of the specimen. 材料能够承受的最大剪切应力。抗剪强度根据剪切或扭转试验期间的最大载荷计算，并基于试样横截面的原始尺寸。 |
| Coarse threads | 粗螺纹 |
Threads with relatively large separation between corresponding points on the threads. 螺纹上相应点之间的间距相对较大的螺纹。 |
| Permissible variation | 允许偏差 |
For testing machines, the maximum allowable error in the value of the quantity indicated. It is convenient to express permissible variation in terms of the percent error. 对于试验机，所示数量值的最大允许误差。用误差百分比表示允许偏差是很方便的。 |
| Austenite stabilization | 奥氏体稳定化 |
Decrease, in comparison to a continuous cooling, in the amount of martensite occurring from austenite when cooling is interrupted at a temperature between Ms and Mf. This can be explained by the relaxation of stresses induced in the austenite by martensite crystals occurring before the interruption. The relaxation, in turn, leads to the dislocation rearrangement and their interaction with martensite/austenite interfaces, which makes the interfaces immobile. 与连续冷却相比，当在Ms和Mf之间的温度中断冷却时，从奥氏体中产生的马氏体的量减少。这可以通过中断前发生的马氏体晶体在奥氏体中引起的应力松弛来解释。反过来，松弛导致位错重排及其与马氏体/奥氏体界面的相互作用，这使得界面无法移动。 |
| 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。 |
| Engineering stress (s) | 工程应力 |
A term sometimes used for conventional stress in order to differentiate it from true stress. In tension testing, it is calculated by dividing the breaking load applied to the specimen by the original crosssectional area of the specimen. 一个术语，有时用于常规应力，以区别于真实应力。在拉伸试验中，通过将施加在试样上的断裂载荷除以试样的原始横截面积来计算。 |
| Congruent melting point (Unit K) | 全等熔点（单位K） |
congruent melting point (Unit K) The temperature at which a solid substance at a specified pressure changes phase to a liquid of identical composition. 一致的熔点（单位K）固体物质在特定压力下相变为具有相同成分的液体时的温度。 |
| Coherent structure | 相干结构 |
A term given to the larger eddies of turbulent shear flow, such as boundary layers, jets, and wakes, that show distinctive correlated patterns of motion. 一个术语，用于表示湍流剪切流的较大涡流，例如边界层、射流和尾流，它们显示出独特的相关运动模式。 |
| Scuffing | 擦伤 |
A form of adhesive wear that produces superficial scratches or a high polish on the rubbing surfaces. It is observed most often on inadequately lubricated parts. 粘着磨损的一种形式，在摩擦表面上产生表面划痕或高度抛光。通常在润滑不足的零件上观察到。 |
| Friction loss (Unit J) | 摩擦损失（单位J） |
The conversion of mechanical energy to heat due to friction within a machine, mechanism, linkage, etc. 由于机器、机构、连杆等内部的摩擦而将机械能转化为热能。 |
| Absolute rating | 绝对标称值 |
A theoretical size designation which is an estimation of the largest particle, by length, that can pass through a filter with a specific 一个理论尺寸名称，它是按长度估算的最大颗粒，它可以通过具有特定过滤器的过滤器 |
| Elongation measurement | 伸张率测量 |
Bolt elongation is directly proportional to axial stress when the applied stress is within the elastic range of the material. If both ends of a bolt are accessible, a micrometer measurement of bolt length made before and after the application of tension will ensure the required axial stress is applied. 当施加的应力在材料的弹性范围内时，螺栓伸长率与轴向应力成正比。如果螺栓的两端都可以接近，则在施加张力前后对螺栓长度进行测微计测量，以确保施加所需的轴向应力。 |
| Castellated nut | 槽形螺母 |
A nut having slots across the hexagonal faces, used with a bolt having a drilled hole so that a split (cotter) pin may be inserted through both nut and bolt to prevent unscrewing. 一种在六角面上有槽的螺母，与具有钻孔的螺栓一起使用，以便将开口（开口）销插入穿过螺母和螺栓以防止拧松。 |
| 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。 |
| Wrinkling | 起皱 |
A wavy condition obtained in deep drawing of sheet metal, in the area of the metal between the edge of the flange and the draw radius. Wrinkling may also occur in other forming operations when unbalanced compressive forces are set up. 在金属板深冲过程中，在法兰边缘和拉深半径之间的金属区域内获得的波浪状状态。当设置不平衡压缩力时，在其他成形操作中也可能发生起皱。 |
| Core | 核心 |
In a ferrous alloy prepared for case hardening, that portion of the alloy that is not part of the case . Typically considered to be the portion that (a) appears light on an etched cross section, (b) has an essentially unaltered chemical composition, or (c) has a hardness, after hardening, less than a specified value. 在为表面硬化而制备的铁合金中，合金中不属于表面的那部分。通常被认为是（a）在蚀刻横截面上看起来很轻，（b）化学成分基本不变，或（c）硬化后硬度低于规定值的那部分。 |
| Quench-age embrittlement | 淬火时效脆化 |
Embrittlement of low-carbon steels resulting from precipitation of solute carbon at existing dislocations and from precipitation hardening of the steel caused by differences in ferrite at different temperatures. Quenchage embrittlement usually is caused by rapid cooling of the steel from temperatures slightly below Ac1 (the temperature at which austenite begins to form), and can be minimized by quenching from lower temperatures. 低碳钢的脆化是由于溶质碳在现有位错处的沉淀和铁素体在不同温度下的差异导致的钢沉淀硬化造成的。淬火脆性通常是由钢从略低于Ac1的温度（奥氏体开始形成的温度）快速冷却引起的，可以通过从较低温度淬火来最小化。 |
| Pressure tap | 测压口 |
A small hole in the wall of a pipe or pressure vessel to which is attached a tube, the other end of which is connected to one side of a pressure transducer. 管子或压力容器壁上的小孔，与管子相连，管子的另一端与压力传感器的一侧相连。 |
| Acoustic separation | 声学分离 |
(Unit m) The separation of particles in a fluid using standing acoustic waves, typically ultrasound, to drive them to nodal points (acoustic particle concentration). （单位m）使用驻声波（通常是超声波）将流体中的粒子分离，以将它们驱动到节点（声学粒子浓度）。 |
| AISC | AISC |
The American Institute of Steel Construction. 美国钢结构学会。 |
| Newton (N) | 牛顿（N） |
The basic unit of force in the SI system, defined as the force that results in an acceleration of 1 m/s² when acting on a 1 kg mass. SI国际单位制中力的基本单位，定义为作用于1kg质量时产生1m/s²加速度的力。 |
| Continuous precipitation | 连续沉淀 |
Precipitation from a supersaturated solid solution in which the precipitate particles grow by longrange diffusion without recrystallization of the matrix. Continuous precipitates grow from nuclei distributed more or less uniformly throughout the matrix. They usually are randomly oriented, but may form a Widmanstätten structure. 来自过饱和固溶体的沉淀，其中沉淀颗粒通过长程扩散生长而无需基质再结晶。连续析出物从在整个基体中或多或少均匀分布的核生长而来。它们通常是随机取向的，但可能形成魏氏结构。 |
| Aerated bath nitriding | 空气搅拌液体渗氮法 |
A type of liquid nitriding in which air is pumped through the molten bath creating agitation and increased chemical activity. 一种液体氮化，其中空气被泵入熔池，产生搅拌并增加化学活性。 |
| Anti-freeze | 防冻液 |
A substance such as ethylene glycol added to the cooling system of a watercooled engine to lower the freezing point of the cooling water and also inhibit the formation of rust and other deposits. 一种物质，如乙二醇，添加到水冷发动机的冷却系统中，以降低冷却水的冰点，并抑制生锈和其他沉积物的形成。 |
| Radial-flow compressor | 离心式压缩机 |
A compressor in which the working gas enters the machine axially and is compressed as it flows radially out through the impeller. 一种压缩机，其中工作气体轴向进入机器，并在通过叶轮径向流出时被压缩。 |
| Cheese head | 圆柱头 |
A cylindrical head on a screw or bolt. For driving, it may be slotted, or hexagonally recessed. 螺钉或螺栓上的圆柱头。为了驱动，它可以是开槽的，也可以是六角形的。 |
| Check valve | 止回阀 |
(clack valve, non-return valve) A mechanical device that allows fluid flow in one direction only. The numerous designs include ball, diaphragm, disc, lift, split disc, and swing check valves. （瓣阀、止回阀）一种仅允许流体单向流动的机械装置。众多设计包括球阀、隔膜阀、盘阀、升降阀、分体盘阀和旋启式止回阀。 |
| Resistance factor | 阻力系数 |
Probabilistic factor representing the uncertainties in the designer’s estimate of the strength of a shear joint. Used in Load and resistance factor design. 概率系数，表示设计人员对剪切接头强度估计的不确定性。用于载荷和阻力系数设计。 |
| 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。 |
| Breaks | 断裂 |
Creases or ridges usually in “untempered” or in aged material where the yield point has been exceeded. Depending on the origin of the break, it may be termed a cross break, a coil break, an edge break, or a sticker break. 通常在“未回火”或超过屈服点的老化材料中出现折痕或隆起。根据断裂的起源，它可能被称为交叉断裂、线圈断裂、边缘断裂或贴纸断裂。 |
| 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。 |
| Tightness parameter | 密封参数 |
A dimensionless parameter which defines the mass leakage of a gasket as a functionof contained pressure and a contained fluid constant. 一种无量纲参数，将垫圈的质量泄漏定义为所含压力和所含流体常数的函数。 |
| Ion carburizing | 离子渗碳 |
A method of surface hardening in which carbon ions are diffused into a workpiece in a vacuum through the use of high-voltage electrical energy. Synonymous with plasma carburizing or glowdischarge carburizing. 一种表面硬化方法，利用高压电能将碳离子在真空中扩散到工件中。与等离子渗碳或辉光放电渗碳同义。 |
| Deformation (Unit 1/s) | 变形（单位1/s） |
A change in the form of a body due to stress, thermal change, change in moisture, or other causes. In solid mechanics, any change, reversible (elastic) or permanent (plastic), in the shape or size of parts of a body, or the whole body, caused by external or internal loading. It includes extension, compression, bending, and twisting. The same state of deformation in a body can appear as different combinations of elongation and shear. To state how much of the total strain is shear, it is split into dilatation and deviatoric components, the former changing volume but not shape, the latter shape but not volume. 由于压力、热变化、水分变化或其他原因导致的身体形态变化。在固体力学中，由外部或内部载荷引起的身体各部分或整个身体的形状或大小的任何可逆（弹性）或永久（塑性）变化。它包括拉伸、压缩、弯曲和扭曲。物体中相同的变形状态可以表现为伸长和剪切的不同组合。为了说明总应变中有多少是剪切，将其分为膨胀分量和偏差分量，前者改变体积但不改变形状，后者改变形状但不改变体积。 |
| Clearance angle | 后角 |
(relief angle) (Unit °) The angle between the underneath or flank of a cutting tool and the machined surface. （后角）（单位°）切削刀具的底部或侧面与加工表面之间的角度。 |
| Design code | 设计规范 |
(design standard) A standard or specification for any aspect of engineering design, issued by national organizations such as ANSI, ASME, BSI, DIN, and ISO. （设计标准）工程设计任何方面的标准或规范，由ANSI、ASME、BSI、DIN和ISO等国家组织发布。 |
| Elasticity | 弹性 |
The property of a material by virtue of which deformation caused by stress disappears on removal of the stress. A perfectly elastic body completely recovers its original shape and dimensions after release of stress. 一种材料的特性，通过这种特性，由应力引起的变形在去除应力后消失。完全弹性体在应力释放后完全恢复其原始形状和尺寸。 |
| Coefficient of discharge (CD) | 流量系数（CD） |
For flow through a nozzle or orifice plate, the ratio of the actual mass flow rate to the theoretical mass flow rate calculated assuming the flow to be isentropic. The coefficient of velocity (velocity coefficient) is the corresponding ratio of the actual average velocity to the theoretical value. For incompressible flow, the theoretical flow rate and velocity can be calculated using Bernoulli’s equation. 对于通过喷嘴或孔板的流量，实际质量流量与假设流量为等熵计算的理论质量流量之比。速度系数（速度系数）是实际平均速度与理论值的对应比。对于不可压缩流，可以使用伯努利方程计算理论流量和速度。 |
| Oil hardening | 油回火 |
The formation of martensite before tempering by quenching suitable steels in oil at lower cooling rates than given by water quenching, thus reducing the likelihood of component fracture or severe residual stresses. Quench-hardening treatment involving cooling in oil. 通过在油中以低于水淬的冷却速率淬火合适的钢，在回火前形成马氏体，从而降低部件断裂或严重残余应力的可能性。是一种淬火硬化处理，包括在油中冷却。 |
| Physical crack size (ap) | 物理裂纹尺寸（ap） |
The distance from a reference plane to the observed crack front. This distance may represent an average of several measurements along the crack front. The reference plane depends on the specimen form, and it is normally taken to be either the boundary or a plane containing either the load line or the centerline of a specimen or plate. 从基准面到观察到的裂纹前沿的距离。该距离可以表示沿裂纹前沿的若干测量的平均值。基准面取决于试样形状，通常视为边界或包含试样或板的载重线或中心线的平面。 |
| 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。 |
| Blank carburizing | 毛坯渗碳 |
Simulating the carburizing operation without introducing carbon. This is usually accomplished by using an inert material in place of the carburizing agent, or by applying a suitable protective coating to the ferrous alloy. 在不引入碳的情况下模拟渗碳操作。这通常通过使用惰性材料代替渗碳剂或通过在铁合金上施加合适的保护涂层来实现。 |
| Stress-intensity calibration | 应力强度校准 |
A mathematical expression, based on empirical or analytical results, that relates the stress-intensity factor to load and crack length for a specific specimen planar geometry. Also known as Kcalibration. 基于经验或分析结果的数学表达式，该表达式将特定试样平面几何形状的应力强度因子与载荷和裂纹长度联系起来。也称为K校准。 |
| Compressometer | 压力计 |
Instrument for measuring change in length over a given gage length caused by application or removal of a force. Commonly used in compression testing of metal specimens. 用于测量在给定标距上由施加或移除力引起的长度变化的仪器。常用于金属试样的压缩试验。 |
| Tare weight (Unit N) | 皮重（单位N） |
The weight of an empty container. 空容器的重量。 |
| Ultimate strength | 极限应力 |
The maximum tensile strength a bolt or material can support prior to rupture. Always found in the plastic region of the stress–strain or force–elongation curve, and so is not a design strength. Also called Tensile strength and ultimate tensile strength. The maximum stress (tensile, compressive, or shear) a material can sustain without fracture, determined by dividing maximum load by the original cross-sectional area of the specimen. Also known as nominal strength or maximum strength. 螺栓或材料在断裂前可支撑的最大抗拉强度。总是出现在应力-应变或力-伸长率曲线的塑性区域，因此不是设计强度。也称为抗拉强度和极限抗拉强度。材料在不断裂的情况下能够承受的最大应力（拉伸、压缩或剪切），通过将最大载荷除以试样的原始横截面积来确定。也称为标称强度或最大强度。 |
| Malleable cast iron | 可锻铸铁 |
A cast iron made by prolonged annealing of white cast iron in which decarburization or graphitization, or both, take place to eliminate some or all of the cementite. The graphite is in the form of temper carbon. If decarburization is the predominant reaction, the product will exhibit a light fracture surface, hence, “whiteheart malleable;” otherwise, the fracture surface will be dark, hence, “blackheart malleable.” Ferritic malleable has a predominantly ferritic matrix; pearlitic malleable may contain pearlitic, spheroidite or tempered martensite depending on heat treatment and desired hardness. 白口铸铁一种通过长时间退火制成的铸铁，脱碳，石墨化，或两者都发生，以消除部分或全部渗碳体。石墨是回火碳的形式。如果脱碳是主要反应，产品将呈现出较轻的断裂表面，“白心可锻”。否则，断裂表面将变暗，“黑心可锻”。铁素体可锻性材料主要为铁素体基体；根据热处理和所需硬度，珠光体可锻材料可能包含珠光体、球状体或回火马氏体。 |
| Mechanical units | 机械单位 |
The units of physical quantities, the dimensions of which includemass, length, and time. 物理量的单位，其量纲包括质量、长度和时间。 |
| Standard hole | 标准孔 |
A hole in a workpiece bored to a specified tolerance where clearance with a shaft is accomplished by allowance on the shaft. A standard shaft is machined to a specified tolerance where clearance with a hole is accomplished by allowance on the hole. 工件上的孔，钻孔至规定公差，其中与轴的间隙通过轴上的余量来实现。标准轴加工至规定公差，其中与孔的间隙通过孔上的公差实现。 |
| Sliding-vane compressor | 滑片压缩机 |
(rotary-vane compressor, vane compressor) A rotary compressor in which gas is compressed as the spaces between spring-loaded sliding vanes held in an offset rotor reduce as the rotor revolves within a cylindrical housing. （旋转叶片压缩机，叶片压缩机）一种旋转式压缩机，当转子在圆柱形外壳内旋转时，偏置转子中的弹簧加载滑动叶片之间的空间减小，从而压缩气体。 |
| Power | 力能 |
The rate of doing work or of producing or consuming energy. The unit of power is the watt, W, where 1 W = 1 N m/s. 做功或产生或消耗能量的速度。功率单位为瓦特，W，其中1W=1N m/s。 |
| Heat capacity (C) (Unit J/K) | 热容量（C）（单位J/K） |
The energy required to raise the temperature of a body by 1K without change of phase. Heat capacity is an extensive thermodynamic property dependent on temperature and pressure. 在不发生相变的情况下将物体的温度提高1K所需的能量。热容量是一种广泛的热力学性质，取决于温度和压力。 |
| Crack | 裂缝 |
A thin fissure-like defect in a component or structure across which material continuity is lost and which reduces the strength of the body. 部件或结构中的细裂缝状缺陷，材料连续性丧失并降低了身体的强度。 |
| 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。 |
| 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。 |
| Thermoelastic effect | 热弹性效应 |
The change in temperature of material under adiabatic elastic deformation, e.g. when loading is so rapid that the material is not in thermal equilibrium with its surroundings. For most materials, elastic tension lowers the temperature and compression raises it. The reverse occurs in elastomers such as rubber that exhibit entropic elasticity because stretching reduces the number of possible molecular configurations and so reduces the entropy. The thermoelastic effect gives rise to a stress–strain hysteresis loop in cyclic elastic loading and is one mechanism by which vibrational energy is dissipated internally in materials. 材料在绝热弹性变形下的温度变化，例如当加载速度如此之快，以至于材料与其周围环境不处于热平衡时。对于大多数材料，弹性张力降低温度，压缩提高温度。相反的情况发生在弹性体中，如橡胶，其表现出熵弹性，因为拉伸减少了可能的分子构型的数量，从而降低了熵。热弹性效应在循环弹性载荷中产生应力-应变迟滞回线，是振动能量在材料内部耗散的一种机制。 |
| International System of Units | 国际单位制 |
(SI system of units, Le Système international d’unités) The standard system of units now used almost universally in science and engineering except in the United States. The definitive reference on the SI is a booklet published by the International Bureau of Weights and Measures, often referred to as the BIPM SI Brochure. There are seven base units: metre (symbol m) for length; kilogram (kg) for mass; mole (mol) for amount of substance; second (s) for time; kelvin (K) for temperature; ampere (A) for electric current; and candela (cd) for luminous intensity. New SI unit definitions, based upon the values of the universal constants of nature (also termed the fundamental physical constants: the Avogadro constant, the Boltzmann constant, and the Planck constant), came into effect on 20 May 2019. Minor adjustments were also made to the values of these constants. In addition to the base units, there are 22 coherent derived units, including radian (rad) for plane angle, steradian (sr) for solid angle, hertz (Hz) for frequency, newton (N) for force, pascal (Pa) for pressure, joule (J) for energy, work, and amount of heat, and watt (W) for power and radiant flux. Recommended practice is to avoid combinations such as N/mm², MN/m² being preferred.(kg) for mass; mole (mol) for amount of substance; second (s) for time; kelvin (K) for temperature; ampere (A) for electric current; and candela (cd) for luminous intensity. New SI unit definitions, based upon the values of the universal constants of nature (also termed the fundamental physical constants: the Avogadro constant, the Boltzmann constant, and the Planck constant), came into effect on 20 May 2019. Minor adjustments were also made to the values of these constants. In addition to the base units, there are 22 coherent derived units, including radian (rad) for plane angle, steradian (sr) for solid angle, hertz (Hz) for frequency, newton (N) for force, pascal (Pa) for pressure, joule (J) for energy, work, and amount of heat, and watt (W) for power and radiant flux. Recommended practice is to avoid combinations such as N/mm², MN/m² being preferred. （国际单位制，Le Système international d\\\'unités）目前美国除外，在科学和工程中几乎是普遍使用的标准单位制。SI的最终参考是国际度量衡局出版的小册子，通常称为BIPM SI小册子。有七个基本单位：米（符号m）表示长度；质量为千克（kg）；物质量的摩尔（mol）；时间为秒；开尔文（K）表示温度；电流为安培（A）；而坎德拉（cd）表示发光强度。新的国际单位制定义于2019年5月20日生效，该定义基于自然界的普遍常数（也称为基本物理常数：阿伏伽德罗常数、玻尔兹曼常数和普朗克常数）。这些常数的值也进行了少量调整。除了基本单位外，还有22个相干导出单位，包括平面角的弧度（rad）、立体角的斯特拉迪安（sr）、频率的赫兹（Hz）、力的牛顿（N）、压力的帕斯卡（Pa）、能量、功和热量的焦耳（J）以及功率和辐射通量的瓦特（W）。建议的做法是避免N/mm²、MN/m²等组合。 |
| Endurance limit | 耐力极限 |
The maximum stress below which a material can presumably endure an infinite number of stress cycles. The value of the maximum stress and the stress ratio also should be stated. That completely reversing stress limit below which a bolt or joint member will have an essentially infinite life under cyclic fatigue loads. Note that the mean stress on the bolts here is zero. 材料可以承受无限次应力循环的最大应力。还应说明最大应力值和应力比。完全逆转的应力极限，低于该极限螺栓或接头构件在循环疲劳载荷下将具有基本上无限的寿命。请注意，此处螺栓上的平均应力为零。 |
| Absorption dynamometer | 吸收式测功机 |
A dynamometer in which input work or power is dissipated by mechanical friction, electrical resistance, hydraulic resistance, etc. 通过机械摩擦、电阻、液压阻力等耗散输入功或功率的测功机。 |
| 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。 |
| Freezing range | 冻融范围 |
That temperature range between liquidus and solidus temperatures in which molten and solid constituents coexist. 熔融和固体成分共存的液相线和固相线温度之间的温度范围。 |
| Longitudinal direction | 纵向 |
The principal direction of flow in a worked metal. See also normal direction and transverse direction. 加工金属中的主要流动方向。另请参见法向和横向。 |
| Pressure difference (Unit Pa) | 压差（单位Pa） |
(pressure differential, Δp) The difference between two pressures, one of which may be a reference pressure such as barometric pressure. In many flow processes, the pressure difference is more important than the absolute pressure level. （压差，Δp）两个压力之间的差值，其中一个压力可以是参考压力，如大气压力。在许多流动过程中，压差比绝对压力水平更重要。 |
| Design pressure (Unit Pa) | 设计压力（单位Pa） |
The greatest pressure that a closed container is expected to experience under normal operating conditions. 密闭容器在正常操作条件下预期承受的最大压力。 |
| Densimeter | 密度计 |
An instrument used to determine the density or relative density of a solid or liquid. 用于测定固体或液体的密度或相对密度的仪器。 |
| Stress distribution | 应力分布 |
The manner in which tensile, compressive, and shear stresses are distributed within a loaded body, indicated by loci of constant stress. 拉应力、压应力和剪应力在受载物体内的分布方式，由恒定应力轨迹表示。 |
| Kiln | 窑 |
An industrial oven for burning, baking, or drying. 用于燃烧、烘烤或干燥的工业烤箱。 |
| Absolute expansion | 绝对扩张 |
The true volumetric expansion of a liquid with temperature, after account is taken of any expansion of the container in which it is held. 考虑到容纳液体的容器的任何膨胀后，液体随温度的真实体积膨胀。 |
| Fatigue notch factor (Kf) | 疲劳缺口系数（Kf） |
The ratio of the fatigue strength of an unnotched specimen to the fatigue strength of a notched specimen of the same material and condition; both strengths are determined at the same number of stress cycles. 无缺口试样的疲劳强度与相同材料和条件的有缺口试样的疲劳强度之比；两种强度都是在相同数量的应力循环下确定的。 |
| Carbon steels | 碳钢 |
(plain carbon steels) Steels in which carbon is the principal alloying element, and the amount of manganese does not exceed 1.65% and the copper and silicon contents are less than 0.60%. There are three main types: low-carbon steels (0.08–0.35% carbon); medium-carbon steels (0.35–0.50% carbon); and high-carbon steels (0.50–2.0% carbon). （普通碳钢）以碳为主要合金元素，锰含量不超过1.65%，铜和硅含量低于0.60%的钢。主要有三种类型：低碳钢（0.08-0.35%碳）；中碳钢（0.35–0.50%碳）；和高碳钢（0.50–2.0%碳）。 |
| Mean stress (Unit Pa) | 平均应力（单位 Pa） |
The average of the maximum and minimum stresses for a material subjected to a stress cycle, as in a fatigue test. 承受应力循环的材料的最大和最小应力的平均值，如在疲劳试验中。 |
| Radioactive heat (Unit J) | 放射性热（单位J） |
Thermal energy released from the nucleus of an atom such as uranium235 by fission due to the absorption of a neutron. Heat is also produced by radioactive decay. 铀235等原子核因吸收中子而裂变释放的热能。放射性衰变也会产生热量。 |
| Fastener specification | 紧固件规格 |
A precise statement of set requirements to be satisfied by a fastener, its material, or its processing. It also indicates the procedure used to determine whether the requirements given are satisfied. 对紧固件、其材料或加工过程要满足的设定要求的精确陈述。它还指出了用于确定是否满足给定要求的程序。 |
| Median fatigue strength at N cycles | N次循环的中位疲劳强度 |
An estimate of the stress level at which 50% of the population would survive N cycles. The estimate is derived from a particular point of the fatigue life distribution, because there is no test procedure by which a frequency distribution of fatigue strengths at Ncycles can be directly observed. 估计50%的量在N个周期内生存的压力水平。该估计值来自疲劳寿命分布的一个特定点，因为没有试验程序可以直接观察N次循环疲劳强度的频率分布。 |
| Nano machining | 纳米加工 |
The machining of silicon chips typically less than 1 nm thick. 硅芯片的加工通常小于1nm厚。 |
| Mole (mol) | 摩尔（mol） |
The base unit of the amount of substance in the SI system. It was previously defined as the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kg of carbon-12. From 20 May 2019 it has been defined as the amount of substance containing exactly 6.022 140 76 × 1023 elementary entities. SI国际单位制中物质量的基本单位。此前，它被定义为一个系统中的物质量，该系统包含的基本实体数量与0.012千克碳-12中的原子数量相同。从2019年5月20日起，它已被定义为包含6.02214076×1023个基本实体的物质量。 |
| Indentation hardness | 压痕硬度 |
The resistance of a material to indentation as determined by hardness testing. The indenter, which may be spherical or diamond shaped, is pressed into the surface of a metal under specified load for a given time. (Unit Pa or, non-SI, kgf/mm²) A measurement of hardness taken by means of an indenter, pressed into a material by a load, which makes a permanent impression. The hardness is given by the load divided by the projected (sometimes surface) area of the indentation. Plasticity theory shows that the hardness is about 2.5–3 times the uniaxial yield stress. 通过硬度测试确定的材料抗压痕的能力。压头可以是球形或菱形，在规定的载荷下压入金属表面一段时间。（单位Pa或，非国际单位制，kgf/mm²）通过压头测量硬度，压入材料，形成永久压痕。硬度由载荷除以压痕的投影（有时是表面）面积得出。塑性理论表明，硬度约为单轴屈服应力的2.5–3倍。 |
| Air compressor | 空气压缩机 |
A turbomachine that draws in air and delivers it at higher pressure, temperature, and density. It can be of axial, fan, reciprocating, or rotary design. 一种涡轮机，它吸入空气并以更高的压力、温度和密度输送空气。它可以是轴流式、风扇式、往复式或旋转式设计。 |
| Damage mechanics | 损伤机制 |
The theory of degradation in bodies, particularly fracture by accumulated microstructural damage. Analyses take two approaches: (a) the use of some critical integrated function of stress and strain at which cracking is initiated and propagated; (b) incorporation of damage in the stress–strain curves to reflect weakened material. 物体退化理论，尤其是累积微观结构损伤导致的断裂。分析采用两种方法：（a）使用裂纹开始和扩展时的应力和应变的一些临界积分函数；（b）应力-应变曲线中包含损伤，以反映弱化材料。 |
| 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。 |
| Tolerances | 公差 |
A fractional allowance for variation from the specifications. In mass production, using automatic machines, parts are intended to be completely or partially interchangeable, and in batch production parts should ideally fit without the need for selection. In practice it is impossible for mass-produced parts to have exactly the same size, owing to tool wear, variations in raw materials, thermal effects, etc. In consequence, variations from exactness, termed tolerances, are assigned to what is permissible on the basic size. 与规范不同的部分公差。在大规模生产中，使用自动机器时，零件应完全或部分可互换，在批量生产中，零件应理想匹配，无需选择。在实践中，由于刀具磨损、原材料变化、热效应等原因，批量生产的零件不可能具有完全相同的尺寸。因此，将精度偏差（称为公差）指定给基本尺寸上允许的尺寸。 |
| Roughness | 粗糙度 |
The deviations from the wavy surface itself, caused by geometry of the cutting tool and its wear, machining conditions, microstructure of the workpiece, vibrations in the system, and so on. Surface roughness changes as a surface goes through the wearing-in process, but may then stabilize. 由刀具的几何形状及其磨损、加工条件、工件的微观结构、系统中的振动等引起的与波状表面本身的偏差。表面粗糙度随着表面经过磨合过程而变化，但随后可能会稳定下来。 |
| Gear ratio | 传动比 |
For two gears in contact, the ratio of the number of teeth on the driving gear to that on the driven gear. 对于接触的两个齿轮，主动齿轮上的齿数与从动齿轮上的齿数之比。 |
| 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。 |
| Rated load (Unit N) | 额定负荷（单位：N） |
The maximum load that a structure or component has been designed to carry. 结构或部件设计承受的最大荷载。 |
| Vacuum annealing | 真空退火 |
Annealing carried out at subatmospheric pressure. 在低于大气压的压力下进行退火。 |
| Sampling frequency (Unit Hz) | 采样频率（单位Hz） |
(sampling rate) The number of measurement samples per unit time taken from a continuous analogue signal to produce a discrete signal. It is the inverse of the time between successive measurements (sampling interval, sampling period, or sampling time). （采样率）从连续模拟信号中提取以产生离散信号的每单位时间的测量样本数。它是连续测量之间时间的倒数（采样间隔、采样周期或采样时间）。 |
| Austenitic grain size | 奥氏体晶粒尺寸 |
The size attained by the grains of steel when heated to the austenitic region; may be revealed by appropriate etching of cross sections after cooling to room temperature. 当加热到奥氏体区域时钢晶粒达到的尺寸；冷却至室温后，可通过适当蚀刻横截面来显示。 |
| Young’s modulus | 杨氏模量 |
A term used synonymously with modulus of elasticity. The ratio of tensile or compressive stresses to the resulting strain. 与弹性模量同义的术语。拉伸或压缩应力与产生应变的比率。 |
| 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。 |
| Sigma-phase embrittlement | σ相脆化 |
Embrittlement of iron-chromium alloys (most notably austenitic stainless steels) caused by precipitation at grain boundaries of the hard, brittle intermetallic sigma phase during long periods of exposure to temperatures between approximately 565 and 980 °C (1050 and 1800 °F). Sigmaphase embrittlement results in severe loss in toughness and ductility and can make the embrittled material structure susceptible to intergranular corrosion. 铁铬合金（最显著的是奥氏体不锈钢）的脆化是由于在长时间暴露于约565至980°C（1050至1800°F）的温度下，硬脆金属间化合物σ相的晶界处沉淀造成的。σ相脆化导致韧性和延展性的严重损失，可使脆化的材料结构易于发生晶间腐蚀。 |
| Forge | 锻造 |
To shape metal while holt and plastic by a hammering or forcing process. Dies used in process. 通过锤击或强制过程使金属成型，同时保持塑料成型。过程会使用模具。 |
| 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。 |
| Rockwell hardness test | 洛氏硬度测试 |
An indentation-hardness test using a calibrated machine that utilizes the depth of indentation, under constant load, as a measure of hardness. A direct-reading hardness test based on depth of indentation, in which a minor load (typically 30 to 100 N) is applied before the major load (typically 120 to 1 500 N). There are different scales using conical or spherical indenters for different ranges of hardness. An indentation hardness test based on the depth of penetration of a specified penetrator into the specimen under certain arbitrarily fixed conditions. 使用校准机器进行的压痕硬度测试，该机器利用恒定载荷下的压痕深度作为硬度测量值。一种基于压痕深度的直读硬度测试，其中在主要载荷（通常为120至1500N）之前施加较小载荷（通常是30至100N）。对于不同的硬度范围，使用锥形或球形压头有不同的刻度。在某些任意固定条件下，基于指定穿透器穿透试样深度的压痕硬度试验。 |
| System engineering | 系统工程 |
A methodology which integrates all disciplines and specialty groups into a team effort, forming a structured development process that proceeds from concept to production to operation. 一种将所有学科和专业组整合到团队工作中的方法，形成从概念到生产再到运营的结构化开发过程。 |
| Mechatronics | 机电一体化 |
The integration of mechanical engineering, electrical engineering, electronic engineering, and software engineering. 机械工程、电气工程、电子工程和软件工程的集成。 |
| Centrifugal pump | 离心泵 |
A pump into which liquid enters axially through the eye of the casing and is then accelerated through an impeller, thereby increasing both its kinetic energy and pressure before being delivered to a ring diffuser (the volute) that further increases the liquid pressure and from which it leaves. 一种泵，液体通过泵壳的眼轴向进入，然后通过叶轮加速，从而在输送到环形扩散器（蜗壳）之前增加其动能和压力，从而进一步增加液体压力并从中流出树叶。 |
| Process annealing | 中间退火 |
An imprecise term denoting various treatments used to improve workability. For the term to be meaningful, the condition of the material and the time-temperature cycle used must be stated. 一个不精确的术语，表示用于改善可加工性的各种处理方法。为了使术语有意义，必须说明材料的条件和使用的时间-温度循环。 |
| Micrometer | 千分尺 |
(micrometer gauge) A mechanical-contact device for the accurate measurement of the length, width, diameter, etc. of an object, the depth of a hole, the height of a step, etc. The usual arrangement is a spindle that is moved by rotation of a thimble, the distance then being read off a vernier scale. （千分尺）一种机械接触装置，用于精确测量物体的长度、宽度、直径等、孔的深度、台阶的高度等。通常的布置是通过顶针的旋转移动主轴，然后通过游标尺读取距离。 |
| Homogeneous carburizing | 均匀渗碳 |
Use of a carburizing process to convert a low-carbon ferrous alloy to one of uniform and higher carbon content throughout the section. 使用渗碳工艺将低碳铁合金转化为整个截面中碳含量均匀且较高的合金。 |
| Balance piston | 平衡活塞 |
(balance drum, dummy piston) A disc attached to the shaft of a turbine or compressor, to one side of which high or low pressure is applied to counteract the axial thrust produced by the pressure change across the machine. A form of thrust bearing. （平衡鼓，假活塞）连接在涡轮机或压缩机轴上的圆盘，在其一侧施加高压或低压，以抵消机器压力变化产生的轴向推力。推力轴承的一种形式。 |
| Chafing fatigue | 磨损疲劳 |
Fatigue damage initiated in a surface damaged by rubbing against another body. 因与另一个物体摩擦而损坏的表面引起的疲劳损坏。 |
| Homogenizing | 均质化 |
Holding at high temperature to eliminate or decrease chemical segregation by diffusion. 保持高温以消除或减少扩散引起的化学偏析。 |
| Boyle’s law | 波义耳定律 |
The product of the pressure of a gas p and its volume is constant at a given absolute temperature T. Together with Charles law, it yields the ideal gas equation p = Mrt where m is the mass of gas and R is the specific gas constant. The volume of a gas at constant temperature is inversely proportional to the pressure. This means that as pressure increases, the volume of a gas decreases. 在给定的绝对温度T下，气体的压力p与其体积的乘积是恒定的。与查尔斯定律一起，它产生了理想的气体方程p=Mrt，其中m是气体的质量，R是特定的气体常数。恒温下气体的体积与压力成反比。这意味着随着压力的增加，气体的体积会减少。 |
| Shear stress (Unit Pa) | 剪应力（单位Pa） |
(1) A stress that exists when parallel planes in metal crystals slide across each other. (2) The stress component tangential to the plane on which the forces act. Also known as tangential stress. (shearing stress, tangential stress, τ) 1. The stress which acts parallel to any plane within a solid material. It can arise due to a bending moment, a shear force, or torque applied to the body. 2. The stress corresponding to velocity gradients within a flowing viscous fluid. （剪应力，切向应力，τ）（1）当金属晶体中的平行平面彼此滑动时存在的应力。（2）与力作用平面相切的应力分量。也称为切向应力。1.平行于固体材料内任何平面的应力。它可能是由于施加在身体上的弯矩、剪力或扭矩引起的。2.对应于流动粘性流体内的速度梯度的应力。 |
| 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。 |
| Tangent modulus | 切线模量 |
The slope of the stress-strain curve at any specified stress or strain. See also modulus of elasticity. 在任何规定的应力或应变下，应力-应变曲线的斜率。另见弹性模量。 |
| Austempered steels | 等温钢 |
Medium to high carbon steels with improved mechanical properties as a result of austempering. After heating to between 800° and 900°C to form the austenite phase, they are quenched to, and held at, just above the martensite transformation range (between 260° and 370°C) to form bainite, before cooling further. Austempering of ductile cast irons results in a microstructure of bainite and spheroidal graphite. Austempered ductile irons have excellent toughness and wear properties. 由于等温淬火，机械性能得到改善的中高碳钢。在加热到800°和900°C之间形成奥氏体相后，将它们淬火并保持在略高于马氏体转变范围（260°和370°C之间）以形成贝氏体，然后进一步冷却。球墨铸铁的等温淬火导致贝氏体和球状石墨的微观结构。等温淬火球墨铸铁具有优异的韧性和耐磨性。 |
| Welding | 焊接 |
In tribology, the bonding between metallic surfaces in direct contact, at any temperature. A joining process in which the mating surfaces are at least softened, or more usually melted, unlike soldering and brazing. In solid-state (non-melting) welding, similar or dissimilar metals or thermoplastics may be joined by applying pressure to hot interfaces. In forge welding, joining is achieved by compression across the join between pre-heated workpieces. In friction welding (spin welding) one of the contacting surfaces is rotated rapidly before being loaded against the other. On contact, heat generated by friction softens the materials and permits severe plastic deformation that seals the joint. In friction stir welding, a wear-resistant tool is rotated rapidly, indents the surfaces and is traversed to form a join line. Resistance welding involves simultaneous pressure and electrically-generated heat, as in spot welding where a heavy electric current is passed for a short time through metal sheets which are pressed together between electrodes. 在摩擦学中，在任何温度下直接接触的金属表面之间的结合。与钎焊和钎焊不同，接合面至少软化或更通常熔化的接合工艺。在固态（非熔化）焊接中，相似或不同的金属或热塑性塑料可通过向热界面施加压力来连接。在锻造焊接中，通过压缩预热工件之间的连接来实现连接。在摩擦焊接（旋转焊接）中，一个接触表面在被加载到另一个表面之前快速旋转。接触时，摩擦产生的热量使材料软化，并允许密封接头的严重塑性变形。在搅拌摩擦焊中，耐磨工具快速旋转，使表面凹陷，并横穿形成连接线。电阻焊涉及同时产生的压力和电产生的热量，如点焊，在点焊中，大电流短时间通过电极之间压在一起的金属板。 |
| Angularity | 角度 |
The underfaces of the nut and the bolt head should be exactly perpendicular to the thread or shank axes. If the angle between the face and the axis is, for example, 868 or 948, the fastener is said to have an angularity of 48 (sometimes called Perpendicularity). 螺母和螺栓头的底面应与螺纹或柄轴完全垂直。例如，如果面和轴之间的角度为868或948，则称紧固件的角度为48（有时称为垂直度）。 |
| 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。 |
| Kinetic energy | 动能 |
Energy that an object possesses because it is in motion. It is the energy given to an object to set it in motion. On impact, it is converted into other forms of energy such as strain, heat, sound and light. 物体因运动而拥有的能量。它是赋予物体使其运动的能量。撞击时，它被转换成其他形式的能量，如应变、热、声和光。 |
| 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。 |
| Lobe | 凸轮 |
The projecting part such as rotor lobe or the cam lobe. 转子凸角或凸轮凸角等突出部分。 |
| Essential conditions | 必要条件 |
Each type of failure to which bolted joints are subject is set up by three or four conditions. The conditions vary, depending on the mode of failure, but never number more than four. Eliminating any one of the essential conditions for a particular type of failure can prevent that type of failure. 螺栓连接所遭受的每种类型的故障都由三个或四个条件确定。根据故障模式的不同，情况会有所不同，但数量不得超过四个。消除特定类型故障的任何一个基本条件都可以防止该类型故障。 |
| Coated abrasive | 涂附磨具 |
An abrasive tool consisting of a flexible backing material, such as a woven cloth, paper or vulcanized fibre, a bond material, such as a glue or synthetic resin, and grit. 一种研磨工具，由柔性背衬材料（例如编织布、纸或硫化纤维）、粘合材料（例如胶水或合成树脂）和砂砾组成。 |
| Atomization | 雾化 |
The production of a spray of fine droplets from a liquid, such as diesel oil or petrol, by injection through a nozzle (an atomizer). 通过喷嘴（雾化器）喷射从液体（例如柴油或汽油）中产生细小液滴喷雾。 |
| Centre line | 中心线 |
1. In an engineering drawing, a line of symmetry. 2. An imaginary line along a pipe, duct, or shaft that defines an axis of symmetry. 3. An imaginary straight line parallel to the intended direction of a surface located such that the areas above and below the line and the real wavy (rough) surface cancel out. 1.在工程图中，对称线。2.沿着管道、管道或竖井定义对称轴的假想线。3.一条平行于表面预期方向的假想直线，该直线上方和下方的区域与真实的波状（粗糙）表面相抵消。 |
| Cavity radiator | 空腔辐射器 |
A heated chamber having a small hole through which radiation, approximating blackbody radiation, passes out. 具有小孔的加热室，近似于黑体辐射的辐射通过该小孔传递出去。 |
| Izod test | 悬臂梁试验 |
A type of impact test in which a V-notched specimen, mounted vertically, is subjected to a sudden blow delivered by the weight at the end of a pendulum arm. The energy required to break off the free end is a measure of the impact strength or toughness of the material. 一种冲击试验，其中垂直安装的V形切口试样受到摆臂末端重量的突然冲击。断开自由端所需的能量是材料冲击强度或韧性的量度。 |
| Destructive testing | 破坏性测试 |
Measurement of the mechanical properties of a material, component, or structure, by increased loading until the sample fails by fracture, collapse, or buckling. 通过增加载荷测量材料、部件或结构的机械性能，直到样品因断裂、塌陷或屈曲而失效。 |
| Offset modulus | 补偿模量 |
The ratio of the offset yield stress to the extension at the offset point (plastics). 偏移屈服应力与偏移点（塑料）处延伸的比率。 |
| Ferrite | 铁素体 |
A solid solution of one or more elements in body-centered cubic iron. Unless otherwise designated (for instance, as chromium ferrite), the solute is generally assumed to be carbon. On some equilibrium diagrams, there are two ferrite regions separated by an austenite area. The lower area is alpha ferrite; the upper, delta ferrite. If there is no designation, alpha ferrite is assumed. 一种或多种元素在体心立方铁中的固溶体。除非另有说明（例如，铁酸铬），否则通常假定溶质为碳。在一些平衡图上，有两个铁素体区域被一个奥氏体区域隔开。下部区域为α铁素体；上部，δ铁氧体。如果没有指定，则假定为 α 铁氧体。 |
| Stress-intensity factor | 应力强度因子 |
A scaling factor, usually denoted by the symbol K, used in linear-elastic fracture mechanics to describe the intensification of applied stress at the tip of a crack of known size and shape. At the onset of rapid crack propagation in any structure containing a crack, the factor is called the critical stress-intensity factor, or the fracture toughness. 一种标度因子，通常用符号K表示，在线弹性断裂力学中用于描述已知尺寸和形状的裂纹尖端施加应力的增强。在任何含有裂纹的结构中，裂纹快速扩展开始时，该因子称为临界应力强度因子，或断裂韧性。 |
| Temper embrittlement | 回火脆化 |
Brittleness that results when certain steels are held within, or are cooled slowly through, a certain range of temperature below the transformation range. The brittleness is manifested as an upward shift in ductile-to-brittle transition temperature but only rarely produces a low value of reduction in area in a smooth-bar tension test of the embrittled material. The anomalous reduction in toughness of martensitic stainless steels when tempered in the range 370–600°C. Embrittlement of alloy steels caused by holding within or cooling slowly through a temperature range just below the transformation range. Embrittlement is the result of the segregation at grain boundaries of impurities such as arsenic, antimony, phosphorus, and tin; it is usually manifested as an upward shift in ductile-to-brittle transition temperature. Temper embrittlement can be reversed by retempering above the critical temperature range, then cooling rapidly. 当某些钢保持在低于转变范围的某一温度范围内或缓慢冷却时产生的脆性。脆性表现为延性到脆性转变温度的向上移动，但在脆性材料的平滑棒材拉伸试验中，很少产生较小的面积减小值。马氏体不锈钢在370–600°C范围内回火时的韧性异常降低。合金钢的脆化是由于在低于转变范围的温度范围内保持或缓慢冷却而引起的。脆化是杂质（如砷、锑、磷和锡）在晶界处偏析的结果；它通常表现为韧脆转变温度的上升。回火脆化可以通过在临界温度范围以上重新回火，然后快速冷却来逆转。 |
| Mohr–Coulomb fracture criterion | Mohr–Coulomb断裂准则 |
A fracture criterion, primarily for brittle materials, according to which failure occurs when the stress at a point in a material falls outside the envelope created by the Mohr’s circles for uniaxial tensile strength and uniaxial compressive strength. 一种断裂准则，主要适用于脆性材料，根据该准则，当材料中某一点的应力落在单轴抗拉强度和单轴抗压强度的莫尔圆所形成的包络线之外时，就会发生断裂。 |
| Bulk density (Unit kg/m³) | 容重（单位kg/m³） |
The average density of a mass of granular or powdered material at ambient conditions. 在环境条件下大量粒状或粉状材料的平均密度。 |
| Contact strength (Unit N) | 接触强度（单位N） |
The maximum allowable load between contacting bodies converted into a stress. 换算成应力的接触体之间的最大允许载荷。 |
| Selective quenching | 局部淬火 |
Quenching only certain portions of an object. 仅淬火工件的某些部分。 |
| Ideal critical diameter | 理想临界直径 |
(DI). Under an ideal quench condition, the bar diameter that has 50% martensite at the center of the bar when the surface is cooled at an infinitely rapid rate (that is, when H = ∞, where H is the quench severity factor). （DI）在理想淬火条件下，当表面以无限快的速度冷却时（即H=∞, 其中H是淬火严重度因子）。 |
| Modulus of resilience | 回弹系数 |
The amount of energy stored in a material when loaded to its elastic limit. It is determined by measuring the area under the stress-strain curve up to the elastic limit. 当加载到其弹性极限时，材料中储存的能量量。通过测量应力-应变曲线下直至弹性极限的面积来确定。 |
| Recrystallization temperature | 再结晶温度 |
The approximate minimum temperature at which complete recrystallization of a cold-worked metal occurs within a specified time. 冷加工金属在规定时间内发生完全再结晶的近似最低温度。 |
| Torsional angle (ϕ) | 扭转角（ψ） |
(Unit ° or rad) The angular deflexion between two locations on a straight bar subjected to a torque. （单位为°或rad）受扭矩作用的直杆上两个位置之间的角偏转。 |
| Fatigue limit for p % survival | p%存活率的疲劳极限 |
The limiting value of fatigue strength for p%survival as the number of stress cycles becomes very large; pmay be any number, such as 95, 90, etc. 随着应力循环次数的增加，p%存活率的疲劳强度极限值变得非常大；p可以是任何数字，例如95、90等。 |
| Two-dimensional flow | 二维流 |
A fluid flow in which the velocity at any time depends upon two spatial coordinates, such as the radial and axial locations in developing pipe flow. 一种流体流动，其中任何时候的速度取决于两个空间坐标，如发展中的管道流中的径向和轴向位置。 |
| U-bolt | U型螺栓 |
A rod threaded at both ends and bent into a U-shape. It is used for clamping. An externally threaded fastener bent in the shape of the letter U and with both ends threaded. 两端有螺纹并弯曲成U形的杆。用于夹紧。一种外螺纹紧固件，弯曲成字母U的形状，两端带有螺纹。 |
| Taper key | 楔键 |
A key with parallel sides but tapering cross section along its length. 边平行但横截面沿其长度逐渐变细的键。 |
| Stiffness | 刚度 |
(1) The ability of a metal or shape to resist elastic deflection.(2) The rate of stress increase with respect to the rate of increase in strain induced in the metal or shape; the greater the stress required to produce a given strain, the stiffer the material is said to be. （1）金属或形状抵抗弹性变形的能力。（2）所述应力增加速率相对于在所述金属或形状中诱导的应变增加速率；产生给定应变所需的应力越大，材料就越硬。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Bypass flow meter | 旁通流量计 |
(shunt flow meter) A flow meter installed in a pipework bypass which may itself be part of the flow meter. An orifice plate is used to ensure a fraction of the main flow passes through the bypass. （分流流量计）安装在管道旁路中的流量计，它本身可能是流量计的一部分。孔板用于确保一部分主流通过旁路。 |
| Elastic resilience | 弹性回弹 |
The amount of energy absorbed in stressing a material up to the elastic limit; or, the amount of energy that can be recovered when stress is released from the elastic limit. 向材料施加应力直至弹性极限所吸收的能量；或者当应力从弹性极限释放时可以恢复的能量值。 |
| Orange peel | 橘皮 |
A surface roughening in the form of a pebble-grained pattern where a metal of unusually coarse grain is stressed beyond its elastic limit. Also known as pebbles and alligator skin. 一种以卵石颗粒图案形式出现的粗糙化表面，其中晶粒异常粗的金属受到的应力超过其弹性极限。也称为卵石和鳄鱼皮。 |
| Fracture strength | 断裂强度 |
(fracture stress) (Unit Pa) The stress at which a material breaks. It is not absolute for a given material, as it depends on the laws of fracture mechanics and is size-dependent. （断裂应力）（单位Pa）材料断裂时的应力。对于给定的材料，它不是绝对的，因为它取决于断裂力学定律，并且取决于尺寸。 |
| 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。 |
| 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。 |
| Concentrated solar power plant (CSP plant) | 聚光太阳能发电厂（CSP发电厂） |
A power plant in which solar radiation is concentrated using mirrors or lenses, typically using parabolic trough mirrors which focus solar radiation on to receiver tubes along the trough’s focal line. In an alternative arrangement molten salt, heated by solar receivers mounted on a tower, is circulated through a steam generator. 使用镜子或透镜集中太阳辐射的发电厂，通常使用抛物面槽镜，将太阳辐射沿着槽的焦线聚焦到接收管上。在另一种布置中，由安装在塔上的太阳能接收器加热的熔盐通过蒸汽发生器循环。 |
| Fine pitch | 细牙螺纹 |
Fine pitch threads are often used within the automotive industry. They are more easily tapped into harder materials and have less tendency to loosen. 细螺距螺纹通常用于汽车行业。它们更容易被敲入较硬的材料中，并且不太容易松动。 |
| Precision | 精确 |
The closeness of agreement between the results of individual replicated measurements or tests. The standard deviation of the error of measurement may be used as a measure of “imprecision.” 单个重复测量或测试结果之间的一致性。测量误差的标准偏差可用作“不精确性”的度量 |
| Mechanical energy (Unit J) | 机械能（单位J） |
The sum of kinetic energy and potential energy for an object or a mechanical system, including the energy stored in springs, etc. 物体或机械系统的动能和势能之和，包括储存在弹簧等中的能量。 |
| Absolute value error | 绝对值误差 |
The magnitude of the error dlsregarding the algebraic sign, or, for a vectorial error, disregarding its function. 关于代数符号的误差幅度，或者，对于矢量误差，不考虑其函数。 |
| 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。 |
| Fitted bolt | 装配螺栓 |
A bolt with a plain unthreaded portion immediately beneath the head. 一种螺栓，其头部正下方有一个普通的无螺纹部分。 |
| Joint diagrams | 接合处关系图 |
Mathematical diagrams which illustrate the forces on and deflections of fasteners and joint members. 说明紧固件和连接件上的力和变形的数学图。 |
| Screw machine | 螺丝机 |
A machine tool for high-volume manufacture of small turned components from rod or bar. 一种用棒或棒大批量制造小零件的机床。 |
| Gear wheel | 齿轮 |
Any form of toothed wheel, particularly those having conjugate teeth employed in the transmission of motion and power. 任何形式的齿轮，特别是用于传递运动和动力的共轭齿的齿轮。 |
| 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。 |
| 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）。 |
| Monotron hardness test | 摩诺硬度试验 |
An obsolete method of determining indentation hardnessby measuring the load required to force a spherical penetrator into a metal to a specified depth. 一种已被淘汰的方法，通过测量将球形侵彻体压入金属至规定深度所需的载荷来确定压痕硬度。 |
| 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。 |
| 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。 |
| Vernier | 游标 |
A short auxiliary scale that slides along the main instrument scale to permit more accurate fractional reading of the least main division of the main scale. 一种短辅助刻度，沿主仪表刻度滑动，以便更准确地读取主刻度的最小主刻度。 |
| Fin | 翼 |
A thin projecting rib. 一根细长的凸肋。 |
| 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。 |
| Shear lip | 剪切唇 |
A narrow, slanting ridge along the edge of a fracture surface. The term sometimes also denotes a narrow, often crescent-shaped, fibrous region at the edge of a fracture that is otherwise of the cleavage type, even though this fibrous region is in the same plane as the rest of the fracture surface. 沿断裂面边缘的狭窄倾斜脊。该术语有时还表示断裂边缘处的狭窄、通常为新月形的纤维区域，否则为解理型，即使该纤维区域与断裂表面的其余部分位于同一平面内。 |
| Stretch forming | 拉伸成型 |
A manufacturing process in which sheet-metal components are physically stretched over a forming die using a press, punch, or edge clamps. Stretching combined with bending reduces springback. 一种制造工艺，其中使用压力机、冲头或边缘夹具在成形模上物理拉伸金属板部件。拉伸与弯曲相结合可减少回弹。 |
| 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。 |
| Preload relaxation | 预载松弛 |
Local yielding, due to excess bearing stress under nuts and bolt heads (caused by high local spots, rough surface finish, and lack of perfect squareness of bolt and nut bearing surfaces), may result in preload relaxation after preloads are first applied to a bolt. 由于螺母和螺栓头下的轴承应力过大（由局部斑点高、表面粗糙以及螺栓和螺母轴承表面缺乏完美的方正度造成），局部屈服可能会在首次向螺栓施加预载荷后导致预载荷松弛。 |
| Bias pressure (Unit Pa) | 偏压（单位Pa） |
In a fluidic device controlled by pressure difference, the magnitude of that difference. 在由压力差控制的流体装置中，该差值的大小。 |
| Principal stress (normal) | 主应力（正常） |
The maximum or minimum value of the normal stressat a point in a plane considered with respect to all possible orientations of the considered plane. On such principal planes the shear stress is zero. There are three principal stresses on three mutually perpendicular planes. The state of stress at a point may be: (1) uniaxial, a state of stress in which two of the three principal stresses are zero; (2) biaxial, a state of stress in which only one of the three principal stresses is zero; or (3) triaxial, a state of stress in which none of the principal stresses is zero. Multiaxial stress refers to either biaxial or triaxial stress. 相对于所考虑平面的所有可能方向，所考虑平面中某点处的法向应力的最大值或最小值。在这样的主平面上，剪切应力为零。在三个相互垂直的平面上有三个主应力。一点的应力状态可以是：（1）单轴，三个主应力中的两个为零的应力；（2）双轴，三个主应力中只有一个为零的应力状态；或（3）三轴，即主应力均不为零的应力状态。多轴应力是指双轴或三轴应力。 |
| Threaded fastener | 螺纹紧固件 |
Studs, bolts, and screws of all sorts, with associated nuts. One of the most interesting, complex, useful—and frustrating—components yet devised. 各种螺柱、螺栓和螺钉，以及相关的螺母。 |
| 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。 |
| Pressure snubber | 压力缓冲器 |
(pressure-pulse snubber) A device used for filtering, dampening, and the protection of transducers, pressure gauges, and switches, from pressure surges, pressure spikes, and water hammer. A typical design uses a fixed mesh or porous metal disc installed in an inline body. In a piston-type pressure-gauge snubber, a piston is forced against an orifice leading to the gauge. （压力脉冲缓冲器）一种用于过滤、阻尼和保护传感器、压力表和开关免受压力浪涌、压力尖峰和水锤影响的装置。典型的设计使用安装在内联阀体中的固定网格或多孔金属盘。在活塞式压力表缓冲器中，活塞被压靠在通向压力表的孔口上。 |
| Maximum material condition | 最大材料条件 |
(maximum metal condition) The situation where the volume of a manufactured component corresponds to the upper limit for all toleranced external dimensions, and to the lower limit for all internal dimensions. （最大金属条件）制造部件的体积对应于所有公差外部尺寸的上限和所有内部尺寸的下限的情况。 |
| 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。 |
| Shear test | 剪切试验 |
Any of several tests to obtain shear strength of a metal. Common tests used on mill products include the double-shear test, single-shear test, the blanking shear test (also known as the punching shear test) and the torsion test. 获得金属剪切强度的几种测试中的任何一种。轧机产品上常用的试验包括双剪试验、单剪试验、落料剪切试验（也称为冲切试验）和扭转试验。 |
| Second (s) | 秒（s） |
The SI base unit of time equal to 9 192 631 770 times the period of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom. SI基时间单位等于9192631770倍的辐射周期，对应于铯-133原子基态的两个超精细能级之间的跃迁。 |
| Double-shear test | 双剪试验 |
A shear test having two stationary, shear blades and one moving one and that uses solid round bars as test specimens. 一种剪切试验，具有两个固定的剪切刀片和一个移动的刀片，并使用实心圆棒作为试样。 |
| 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。 |
| Fin neck carriage bolt | 翼颈圆头方颈螺栓 |
A plain, circular, oval head bolt with two oppositely located fins to prevent rotation. 一种普通的圆形椭圆头螺栓，有两个相对的翼片以防止旋转。 |
| Graphitization | 石墨化 |
Formation of graphite in iron or steel. Where graphite is formed during solidification, the phenomenon is called primary graphitization; where formed later by heat treatment, secondary graphitization. 在铁或钢中形成石墨。在凝固过程中形成石墨的现象称为一次石墨化；后来通过热处理，形成二次石墨化。 |
| Centrifugal force (Unit N) | 离心力（单位N） |
The inertial reaction force to the centripetal force. It is equal in magnitude but opposite in direction. 惯性反作用力对向心力。它的大小相等，但方向相反。 |
| 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。 |
| Volumetric efficiency | 容积效率 |
For a piston engine, the ratio of the volume of the induced charge per induction stroke, determined at a reference pressure and temperature, to the swept volume. 对于活塞式发动机，在参考压力和温度下确定的每个进气冲程的进气体积与扫掠体积之比。 |
| Adhesive wear | 粘着磨损 |
Wear that develops when two surfaces slide across one another under pressure. The removal or displacement of material from a surface by the welding together and subsequent shearing of minute areas of two surfaces that slide across each other under pressure. In advanced stages, may lead to galling. Contrast with abrasive wear. 当两个表面在压力下相互滑动时产生的磨损。通过焊接在一起并随后剪切在压力下相互滑动的两个表面的微小区域，从表面去除或置换材料。在晚期，可能会导致擦伤。与磨料磨损形成对比。 |
| Impact strength 1. (Unit Pa) | 冲击强度1.（单位Pa） |
The stress to cause failure (by yielding or fracture) under conditions of high strain rate. 2. (Unit J) A term sometimes used to describe the energy required to fracture a specimen in a Charpy or Izod impact test even though the unit is not that of strength. 在高应变率条件下导致失效（通过屈服或断裂）的应力。2.（单位J）有时用于描述在夏比或悬臂梁式冲击试验中使样品断裂所需的能量，即使单位不是强度单位。 |
| Maximum-and-minimum thermometer | 最高和最低温度计 |
(minimum-maximum thermometer, Six’s thermometer) A liquid-in-glass instrument designed to register the maximum and minimum temperatures experienced over a given time period. （最低-最高温度计，Six's温度计）一种液体玻璃仪器，用于记录给定时间段内经历的最高和最低温度。 |
| Plug gauge | 塞规 |
A steel gauge used to determine the dimension or dimensions of a hole. It may be straight or tapered, and is typically circular, but in principle can have any cross section. 用于确定孔的尺寸的钢制量规。它可以是直的或锥形的，通常是圆形的，原则上可以有任何横截面。 |
| Structural frame | 结构框架 |
The underlying load-bearing framework of beams, columns, bracing, etc., of steel, concrete, brick, stone, timber etc., required to support the static and dynamic forces a building or component is subjected to, including its weight and that of its contents. 由钢、混凝土、砖、石、木材等制成的梁、柱、支撑等构成的底层承重框架，用于支撑建筑物或构件承受的静态和动态力，包括其重量及其内含物的重量。 |
| Coalescence | 聚结 |
Growth of grains at the expense of the remainder by absorption or the growth of a phase or particle at the expense of the remainder by absorption or reprecipitation. 通过吸收以牺牲剩余为代价的晶粒的生长或以通过吸收或再沉淀为代价的以剩余为代价的相或颗粒的生长。 |
| Typical basis | 典型基础 |
The typical property value is an average value. No statistical assurance is associated with this basis. 典型的属性值是平均值。没有与此基础相关的统计保证。 |
| Dowel | 销钉 |
A headless cylindrical pin that fits into corresponding holes in mating components, thus ensuring relative location. A round metal or wooden pin. A pin, usually of circular shape like a cylinder, used to pin or fasten something in position temporarily or permanently. 一种圆头金属或木制圆柱销，可插入配合组件的相应孔中，从而确保相对位置，用于暂时或永久地将某物固定或固定到位。 |
| Torque converter | 变矩器 |
A turbomachine used for torque amplification consisting of an impeller, a turbine, and a reaction member. Applications include motor-vehicle transmissions. 用于扭矩放大的涡轮机，由叶轮、涡轮机和反作用构件组成。应用包括机动车变速器。 |
| Collapse load (Unit N) | 毁坏荷载（单位N） |
The applied load at which a structure becomes a mechanism owing to the formation of sufficient plastic hinges for collapse to occur. 由于形成足够的塑性铰链以发生坍塌，结构成为机制的施加载荷。 |
| Overheating | 过热 |
Heating a metal or alloy to such a high temperature that its properties are impaired. When the original properties cannot be restored by further heat treating, by mechanical working, or by a combination of working and heat treating, the overheating is known as burning. 将金属或合金加热至其性能受损的高温。当通过进一步热处理、机械加工或加工与热处理的组合无法恢复原始性能时，过热称为燃烧。 |
| Degrees of freedom | 自由度 |
The number of independent variables (such as temperature, pressure, or concentration within the phases present) that may be altered at will without causing a phase change in an alloy system at equilibrium; or the number of such variables that must be fixed arbitrarily to define the system completely. 可以随意改变而不引起平衡时合金系统相变的自变量的数量（例如存在的相内的温度、压力或浓度）；或必须任意固定以完全定义系统的此类变量的数量。 |
| 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）。 |
| Thermal analysis | 热分析 |
A method for determining transformations in a metal by noting the temperatures at which thermal arrests occur. These arrests are manifested by changes in slope of the plotted or mechanically traced heating and cooling curves. When such data are secured under nearly equilibrium conditions of heating and cooling, the method is commonly used for determining certain critical temperatures required for the construction of equilibrium diagrams. 一种通过记录发生热阻的温度来确定金属转变的方法。这些阻力表现为绘制或机械追踪的加热和冷却曲线斜率的变化。当这些数据在加热和冷却的近似平衡条件下得到保证时，该方法通常用于确定构建平衡图所需的某些临界温度。 |
| 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。 |
| Fatigue limit | 疲劳极限 |
The maximum stress that presumably leads to fatigue fracture in a specified number of stress cycles. The value of the maximum stress and the stress ratio also should be stated. Compare with endurance limit. 在指定数量的应力循环中可能导致疲劳断裂的最大应力。还应说明最大应力值和应力比。与耐力极限比较。 |
| Breaking load | 断裂载荷 |
The maximum load (or force) applied to a test specimen or structural member loaded to rupture. 施加到加载到破裂的试样或结构构件上的最大载荷（或力）。 |
| Bypass ratio | 旁路比 |
In a turbofan engine, the ratio of the mass flow rate of the bypass stream to the mass flow rate through the core of the engine. 在涡扇发动机中，旁通流的质量流量与通过发动机核心的质量流量之比。 |
| Arbitration bar | 抗弯试棒 |
A test bar, cast with a heat of material, used to determine chemical composition, hardness, tensile strength, and deflection and strength under transverse loading in order to establish the state of acceptability of the casting. 用热材料铸造的测试棒，用于确定化学成分、硬度、抗拉强度、横向载荷下的挠度和强度，以确定铸件的可接受状态。 |
| 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。 |
| DTI | DTI |
Direct tension indicator. A fastener used primarily in the structural steel industry, designed to indicate that a certain minimum amount of tension has been developed in the fastener during assembly. 直接张力指示器。一种主要用于结构钢行业的紧固件，旨在表明在装配过程中紧固件中产生了一定的最小张力。 |
| Yield strength | 屈服强度 |
That stress level which will create a permanent deformation of 0.2% or 0.5% or some other small, preselected, amount in a body. Approximately equal to the elastic and proportional limits of the material; a little higher than the proof strength of a bolt. The stress at which a material exhibits a specified deviation from proportionality of stress and strain. An offset of 0.2% is used for many metals. 该应力水平将在物体中产生0.2%或0.5%的永久变形，或其他一些小的、预先选定的量。近似等于材料的弹性和比例极限；略高于螺栓的强度。材料表现出与应力和应变比例的特定偏差的应力。许多金属使用0.2%的偏移量。 |
| Hydrodynamics | 流体力学 |
A term sometimes used to mean fluid dynamics, even when the fluid is a gas or a liquid other than water. 有时用于表示流体动力学的术语，即使流体是气体或水以外的液体。 |
| Minor diameter | 螺纹小径 |
On a straight thread, the diameter of the imaginary cylinder which just touches the root of an external thread or the crest of an internal thread. 在直螺纹上，仅接触外螺纹根部或内螺纹顶部的假想圆柱体的直径。 |
| Pitch diameter | 中径 |
For screw threads, the diameter of an imaginary cylinder, the surface of which would pass through the threads at such points that would make the width of the groove and width of the land equal to one half the pitch. 对于螺纹，指一个假想圆柱体的直径，其表面将在使凹槽宽度和焊盘宽度等于螺距一半的点穿过螺纹。 |
| Steady pin | 定位销 |
A dowel, key, or pin that prevents a pulley from turning on its shaft. 防止滑轮在其轴上转动的销钉、键或销。 |
| 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。 |
| Preload accuracy | 预载精度 |
A measure of the precision with which a given tool or procedure creates preload in a bolt when the bolt is tightened. A common torque wrench, for example, is said to produce preload with an accuracy of +30%. The mean preload, however, may not be that which the designer intended, or may not be what he should have intended. Accuracy as used here, in other words, is synonymous with Scatter. 当螺栓拧紧时，给定工具或程序在螺栓中产生预紧力的精度度量。例如，一个普通的扭矩扳手据说可以产生精度为+30%的预载。然而，平均预载可能不是设计者预期的。这里使用的准确度是分散度的同义词。 |
| Caustic quenching | 苛性淬火 |
Quenching with aqueous solutions of 5 to 10% sodium hydroxide (NaOH). 用5%至10%氢氧化钠（NaOH）水溶液淬灭。 |
| Stove bolt | 炉用螺栓 |
This bolt has been so named because of its use in stove building. It is made in a number of different forms, either with a round button, or flat countersunk head, the head having a slot for a screwdriver and the threaded end being provided with a square or hexagon nut. 这种螺栓因其在炉灶建筑中的用途而得名。它有多种不同的形式，有圆形按钮或平沉头，头部有螺丝刀槽，螺纹端有方形或六角螺母。 |
| 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。 |
| 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。 |
| Turbine flow meter | 涡轮流量计 |
(axial flow meter, propeller meter) An in-line flow meter in which the rotation speed N of a propeller or rotor is a measure of the mass flowrate ṁ. Calibration is always necessary but with appropriate design ṁ is closely proportional to N over a wide range. （轴向流量计、螺旋桨流量计）一种串联流量计，其中螺旋桨或转子的转速N是质量流量的测量值ṁ. 校准总是必要的，但需要适当的设计ṁ在很宽的范围内与N成正比。 |
| 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。 |
| Kelvin (K) | 开尔文（K） |
The SI unit of temperature. The Kelvin temperature scale has a zero point at absolute zero and degree intervals (kelvins) the same size as degrees Celsius. The freezing point of water occurs at 273K (0ºC) and the boiling point at 373 K (100ºC). The base unit of thermodynamic temperature in the SI system. It was previously defined to be the fraction 1/273.16 of the thermodynamic temperature of the triple point of water. From 20 May 2019 it has been defined by taking the fixed numerical value of the Boltzmann constant kB to be 1.380 649 × 10−23 when expressed in the unit J/K, which is equal to kg.m²/(s²K). 国际单位制中热力学温度的基本单位。开尔文温度标度在绝对零度和与摄氏度大小相同的度间隔（开尔文）处有一个零点。水的冰点为273K（0ºC），沸点为373K（100ºC）。它先前被定义为水三相点热力学温度的分数1/273.16。从2019年5月20日起，通过将玻尔兹曼常数kB的固定数值取为1.380649×10来定义−当以等于kg·m²/（s²K）的单位J/K表示时。 |
| Interrupted quenching | 间断淬火 |
A quenching procedure in which the workpiece is removed from the first quench at a temperature substantially higher than that of the quenchant and is then subjected to a second quenching system having a different cooling rate than the first. 在该淬火过程中，工件在显著高于淬火剂的温度下从第一次淬火中取出，然后经受具有不同于第一次淬火的冷却速率的第二次淬火系统。 |
| Constant life diagram | 恒定寿命图 |
A plot of experimentally derived fatigue-life data; perhaps the most complex and complete of the popular charts used to represent such data. 实验得出的疲劳寿命数据图；可能是用于表示此类数据的最复杂和最完整的流行图表。 |
| Damage tolerance | 损伤容限 |
(defect tolerance) A design philosophy that takes into account initial imperfections, crack-growth rates and conditions at final fracture, and uses fracture mechanics to demonstrate that cracks should not grow to their critical length within the design life (or at least should be capable of ready detection). （缺陷公差）考虑初始缺陷、裂纹扩展速率和最终断裂条件的设计理念，并使用断裂力学证明裂纹不应在设计寿命内增长到其临界长度（或至少应能够随时检测）。 |
| Depth gauge | 深度计 |
1. A precision instrument, typically consisting of a machine-divided steel rule passing through a hardened-steel cross head, used to measure the depths of slots, holes, shoulders, projections, etc. 2. A device used by divers to indicate the water depth. 1. 一种精密仪器，通常由穿过硬化钢十字头的机器分割钢尺组成，用于测量槽、孔、肩部、突起等的深度。 2. 潜水员用来指示深度的装置水深。 |
| Shear fracture | 剪切断裂 |
A ductile fracture in which a crystal (or a polycrystalline mass)has separated by sliding or tearing under the action of shear stresses. Contrast with cleavage fracture. 在剪切应力作用下，晶体（或多晶块）通过滑动或撕裂而分离的韧性断裂。与解理断裂形成对比。 |
| Degradation | 降解 |
The reduction with time of the physical properties of a material. 材料的物理性质随时间的减少。 |
| Clip gauge | 夹规 |
A displacement gauge consisting of two thin strain-gauged cantilever arms attached through knife edges to a testpiece to give the load–line displacement in fracture mechanics test pieces, or used as an extensometer in tensile tests. 一种位移计，由两个通过刀刃连接到试件上的薄应变测量悬臂组成，以提供断裂力学试件中的载荷线位移，或用作拉伸试验中的引伸计。 |
| Sigma phase | σ相 |
A hard, brittle, nonmagnetic intermediate phase with a tetragonal crystal structure, containing 30 atoms per unit cell, space group P42/mnm, occurring in many binary and ternary alloys of the transition elements. The composition of this phase in the various systems is not the same, and the phase usually exhibits a wide range in homogeneity. Alloying with a third transition element usually enlarges the field of homogeneity and extends it deep into the ternary section. 一种硬、脆、非磁性中间相，具有四方晶体结构，每单位晶胞含有30个原子，空间群P42/mnm，存在于许多过渡元素的二元和三元合金中。该相在各种系统中的组成不尽相同，并且该相通常表现出宽范围的均匀性。与第三过渡元素的合金化通常会扩大均匀性范围，并将其延伸到三元区。 |
| Recrystallization annealing | 再结晶退火 |
Annealing cold-worked metal to produce a new grain structure without phase change. 退火冷加工金属以产生新的晶粒结构而不发生相变。 |
| Honing | 珩磨 |
Honing is a controlled, low-speed sizing and surface-finishing process in which stock is removed by the shearing action to the bonded abrasive grains of a honing stone, or stick. Finish polishing of surfaces and cutting edges in which very fine abrasive powders, such as rouge, are employed. Honing is usually applied to cylindrical surfaces and lapping to flat, but the usage is not consistent. 珩磨是一种受控的低速尺寸和表面精加工工艺，其中通过对珩磨石或棒的粘结磨粒的剪切作用去除原料。表面和切削刃的精抛光，其中使用了非常细的研磨粉，例如胭脂。珩磨通常用于圆柱面，研磨至平面，但用法并不一致。 |
| 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。 |
| Dynamic strain aging | 动态应变时效 |
A behavior in metals in which solute atoms are sufficiently mobile to move toward and interact with dislocations. This results in strengthening over a specific range of elevated temperature and strain rate. 金属的一种特点，其中溶质原子具有足够的移动能力，能够向位错移动并与位错相互作用，会导致在特定的高温和应变速率范围内强化。 |
| Radiation pressure (Unit μPa) | 辐射压力（单位：μPa） |
The pressure exerted on a surface exposed to any form of electromagnetic radiation. If the radiation is absorbed, it is equal to the power-flux density divided by the speed of light. 施加在暴露于任何形式电磁辐射的表面上的压力。如果辐射被吸收，它等于功率通量密度除以光速。 |
| Anode | 阳极 |
That electrode in a battery or corrosion cell which produces electrons. It is the electrode which is destroyed (corrodes). 电池或腐蚀电池中产生电子的电极。被破坏（腐蚀）的是电极。 |
| T-bolt | T型螺栓 |
A threaded bolt having a square or rectangular end which fits into the T slot of a machine table for clamping workpieces. 一种带有方形或矩形端头的螺栓，可嵌入机床工作台的T形槽中，用于夹紧工件。 |
| Computer control | 电脑控制 |
The control of an engineering device or system by pre-programmed computer or by feedback control. 通过预编程计算机或反馈控制对工程设备或系统进行控制。 |
| Bucket | 吊桶 |
1. A cup-shaped vane with a central dividing ridge attached to the periphery of the runner of an impulse water turbine such as a Pelton turbine. 2. A rotor blade in a compressor or turbine. 1.一种杯形叶片，所述杯形叶片具有附接到冲击式水轮机（例如冲击式水轮机台）的转轮的外围的中央分隔脊。2.压缩机或涡轮机中的转子叶片。 |
| Double tempering | 双回火 |
A treatment in which a quench-hardened ferrous metal is subjected to two complete tempering cycles, usually at substantially the same temperature, for the purpose of ensuring completion of the tempering reaction and promoting stability of the resulting microstructure. 一种处理，其中淬火硬化的黑色金属经过两个完整的回火循环，通常在基本相同的温度下，以确保完成回火反应并提高所得微观结构的稳定性。 |
| Crystalline defects | 结晶缺陷 |
The deviations from a perfect three-dimensional atomic packing that are responsible for much of the structure-sensitive properties of the materials. Crystal defects can be point defects (dislocations) or surface defects (vacancies), line defects (dislocations), or surface defects (grain boundaries). 与完美的三维原子堆积的偏差是造成材料的大部分结构敏感特性的原因。晶体缺陷可以是点缺陷（位错）或表面缺陷（空位）、线缺陷（位错）或表面缺陷（晶界）。 |
| Plane-strain fracture toughness (KIc) | 平面应变断裂韧性（KIc） |
The crack extension resistance under conditions of crack-tip plane strain. 裂纹尖端平面应变条件下的裂纹扩展阻力。 |
| Oil quenching | 油淬 |
Hardening of carbon steel in an oil bath. Oils are categorized as conventional, fast, martempering, or hot quenching. 碳钢在油浴中的硬化。分为常规、快速、马氏体淬火或热淬火。 |
| Archimedes screw | 阿基米德螺旋泵 |
A machine which comprises a rotating helical blade inside a closefitting tube, which may be used to pump liquids, slurries (such as sewage), granular materials, etc. If water flows into the top of an inclined or vertical Archimedes screw, the screw will rotate and can be used to drive an electrical generator. 一种机器，它在紧密的管子内包含一个旋转的螺旋叶片，可用于泵送液体、泥浆（如污水）、颗粒材料等。如果水流入倾斜或垂直的阿基米德螺杆的顶部，螺杆将旋转，可用于驱动发电机。 |
| Blank nitriding | 空白渗氮 |
Simulating the nitriding operation without introducing nitrogen. This is usually accomplished by using an inert material in place of the nitriding agent or by applying a suitable protective coating to the ferrous alloy. 在不引入氮气的情况下模拟氮化操作。这通常通过使用惰性材料代替氮化剂或通过在铁合金上施加合适的保护涂层来实现。 |
| Band clutch | 带式离合器 |
A friction clutch in which drive is achieved by a band contracting on to the rim of the clutch. 一种摩擦离合器，其驱动是通过一条带在离合器边缘上收缩来实现的。 |
| 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。 |
| Fastener quality | 紧固件质量 |
A fastener’s adherence to its specification for dimensional tolerances, mechanical properties, and other requirements stated under applicable standards. 紧固件对尺寸公差、机械性能和适用标准规定的其他要求的规范的遵守情况。 |
| Yielding | 屈服 |
Evidence of plastic deformation in structural materials. Also known as plastic flow or creep. 结构材料塑性变形的证据。也称为塑性流动或蠕变。 |
| Corrosion cell | 腐蚀电池 |
A natural ‘‘battery’’ formed when two metals having different electrical potentials (an Anode and a Cathode) are connected together in the presence of a liquid (the Electrolyte). 当两种具有不同电势的金属（阳极和阴极）在液体（电解质）存在下连接在一起时形成的天然“电池”。 |
| Coupling | 耦合 |
A detachable mechanism forming a joint. A connector of two components of a joint. 1. Any mechanical fastening connecting two or more shafts, or parts of a mechanism, in order to transmit power. 2. A device for connecting two vehicles. 一种形成关节的可拆卸机构。关节的两个组件的连接器。1.连接两个或多个轴或机构部件的任何机械紧固件，以传递动力。2.连接两辆车的装置。 |
| 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。 |
| Solution heat treatment | 固溶热处理 |
Heating an alloy to a suitable temperature, holding at that temperature long enough to cause one or more constituents to enter into solid solution, and then cooling rapidly enough to hold these constituents in solution. 将合金加热到合适的温度，在该温度下保持足够长的时间以使一种或多种成分进入固溶体，然后快速冷却以将这些成分保持在溶液中。 |
| 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。 |
| Wind pump | 风泵 |
A pump driven directly by a windmill on a tower. Widely used in remote locations. 由塔上的风车直接驱动的泵。广泛应用于偏远地区。 |
| Tensometer | 拉力计 |
A bench-top device, used to perform tension and compression tests. 用于进行拉伸和压缩试验的台式装置。 |
| Turbocharging | 涡轮增压 |
A method of supercharging in which the hot exhaust gas from a piston engine is used to drive a turbine which powers the supercharging compressor. A turbocharger is the turbine/compressor combination. The compressor is usually of radial outflow design while radial, axial, and mixed-flow turbines are all in use. The wastegate is a valve that reduces the flow of exhaust gas into the turbine to limit the boost produced or overspeeding. Not shown in the diagram are bearings, oil passages, etc. 一种增压方法，其中活塞发动机的热废气用于驱动涡轮，涡轮为增压压缩机提供动力。涡轮增压器是涡轮/压缩机组合。压缩机通常为径向流出设计，而径向、轴向和混流式涡轮机都在使用。废气旁通阀是一种减少进入涡轮的废气流量以限制产生的增压或超速的阀。 |
| 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。 |
| Columnar structure | 柱状结构 |
A coarse structure of parallel elongated grains formed by unidirectional growth, most often observed in castings, but sometimes in structures resulting from diffusional growth accompanied by a solid-state transformation. 由单向生长形成的平行细长晶粒的粗略结构，最常见于铸件中，但有时也出现在伴随固态转变的扩散生长产生的结构中。 |
| Reverse engineering | 逆向工程 |
The disassembly of a machine, mechanism, system or device, measurement of its component parts, and identification of the materials used so that if required, a functioning replica can be produced. 拆卸机器、机构、系统或装置，测量其组成部分，并识别所用材料，以便在需要时可以生产出功能正常的复制品。 |
| Cavitation damage | 气蚀损坏 |
Erosion of a solid surface through the formation and collapse of cavities or bubbles in an adjacent liquid that contains vapor and/or gas. 通过在包含蒸汽和/或气体的相邻液体中形成空穴或气泡并破坏固体表面。 |
| Static equilibrium | 静态平衡 |
A solid body, structure, or physical system (or any subdivided part) will be in static equilibrium, either at rest or moving with constant velocity, if the resultants of all external forces and moments acting on it are zero. 如果作用在固体上的所有外力和力矩的合力为零，则固体、结构或物理系统（或任何细分部分）无论是静止还是以恒定速度移动，都是处于静态平衡。 |
| Clevis | U形夹 |
A U-shaped hook with holes at the ends through which a retaining bolt or pin (clevis pin) passes. 一种U形钩，末端有孔，固定螺栓或销（U形销）穿过这些孔。 |
| Pump | 泵 |
A machine designed to cause a liquid, gas, vapour, or slurry to flow due to the reciprocating motion of pistons, rotation of vanes, or rotation of an impeller. 通过活塞的往复运动、叶片的旋转或叶轮的旋转而使液体、气体、蒸汽或泥浆流动的机器。 |
| Ball mill | 球磨机 |
A mill for grinding and pulverizing materials, consisting of a horizontal rotating drum containing loose steel or ceramic balls. 一种用于研磨和粉碎物料的磨机，由装有松散钢球或陶瓷球的水平旋转滚筒组成。 |
| Dynamic recovery | 动态恢复 |
A process occurring in hot working of metals in which a fine subgrain structure forms within the elongated grains due to annihilation of dislocations due to easy cross slip and climb. It results in a lowering of the flow stress. Dynamic recovery, as opposed to dynamic recrystallization that occurs in hot working, occurs in metals of high stacking fault energy such as aluminum, αiron, and most bcc metals. 金属热加工中发生的一种过程，由于易于交叉滑动和攀爬，位错湮灭，细长晶粒内形成细亚晶粒结构。这导致流动应力降低。与热加工中发生的动态再结晶相反，动态回复发生在高层错能金属中，如铝、α铁和大多数bcc金属。 |
| Degradation of energy | 能源退化 |
Conversion of energy into forms of lower usefulness due to irreversibilities in energy transfer and conversion processes. The increase in entropy can be regarded as a measure of the degradation of energy. 由于能量转移和转换过程中的不可逆性，将能量转换为低效形式。熵的增加可以看作是能量退化的量度。 |
| Abrasive wear | 磨料磨损 |
The removal or displacement of material from a surface when hard particles slide or roll across the surface under pressure. The particles may be loose or may be part of another surface in contact with the surface being worn. Contrast with adhesive wear. 当硬质颗粒在压力下在表面上滑动或滚动时，材料从表面上的去除或位移。颗粒可能是松散的或可能是与被磨损表面接触的另一个表面的一部分。与粘着磨损形成对比。 |
| 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。 |
| Constant-force spring | 恒力弹簧 |
A spring that has the same restoring force regardless of displacement. The most common type takes the form of a coiled strip that, owing to tight coiling during manufacture, is pre-stressed (a steel measuring tape is an example). The uncoiling force is approximately constant as the change of curvature of the strip is approximately constant. Not to be confused with a clockwork spring from which power can be obtained. 无论位移如何，具有相同恢复力的弹簧。最常见的类型是卷绕带，由于制造过程中的紧密卷绕，该卷绕带是预应力的（钢卷尺就是一个例子）。随着带材曲率的变化近似恒定，开卷力近似恒定。不要与可获得动力的发条弹簧混淆。 |
| 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。 |
| Base metal hardness | 母材硬度 |
Hardness closest to the surface (when traversing from core to outside diameter) just before an increase or decrease occurs, denoting, respectively, carburization or decarburization. 在发生增加或减少之前最接近表面的硬度（从芯部到外径时），分别表示渗碳或脱碳。 |
| 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。 |
| Bearing stress | 承受应力 |
The force per unit of bearing area. 每单位承载面积的力。 |
| Decarburization | 脱碳 |
Loss of carbon from the surface layer of a carbon-containing alloy due to reaction with one or more chemical substances in a medium that contacts the surface. 由于与接触表面的介质中的一种或多种化学物质发生反应，含碳合金表面层的碳损失。 |
| Tensile test (tension test) | 拉伸试验（拉力试验） |
A test in which a precisely-machined tensile specimen (tensile testpiece), typically circular or rectangular in cross section with large end sections that are gripped in the testing machine, is subjected to an increasing tensile load, usually to the point of fracture, to produce a stress–strain curve from which such material properties as modulus of elasticity, limit of proportionality, proof stress, yield point, and ultimate tensile stress can be determined. The relevant standard is ISO 6892-1. 一种试验，在这种试验中，精密加工的拉伸试样（拉伸试件）的横截面通常为圆形或矩形，具有在试验机中夹紧的大端部，受到越来越大的拉伸载荷，通常达到断裂点，以产生应力-应变曲线，从中可以看出弹性模量、比例极限等材料特性，可以确定验证应力、屈服点和极限拉伸应力。相关标准为ISO 6892-1。 |
| Hydrogen damage | 氢损伤 |
A general term for the embrittlement, cracking, blistering, and hydride formation that can occur when hydrogen is present in some metals. 当氢存在于某些金属中时可能发生的脆化、开裂、起泡和氢化物形成的总称。 |
| Volume (Unit m³) | 体积（单位m³） |
The amount of space occupied by a specified mass of substance or by an object. 一定质量的物质或物体占据的空间量。 |
| 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。 |
| Secondary hardening | 二次硬化 |
The process whereby some low-alloy steels, quenched to produce martensite, produce fine precipitates when tempered above 550°C, which inhibit dislocation motion and reverse the trend towards lower strength at higher tempering temperatures. 某些低合金钢经淬火产生马氏体，在550°C以上回火时产生细小沉淀的过程，这抑制了位错运动，扭转了在较高回火温度下强度降低的趋势。 |
| Counter sink | 台面水槽 |
To cut or shape a depression in an object so that the head of a screw may set flush or below the surface. 在物体上切割或塑造一个凹陷，使螺钉的头部可以齐平或低于表面。 |
| 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。 |
| Cold working | 冷加工 |
The plastic deformation of a metal, by rolling (cold rolling), drawing, forging (cold forging), etc. at a temperature well below its recrystallization temperature, which results not only in permanent shape change but also increase in strength and loss of ductility owing to work-hardening. 金属在远低于其再结晶温度的温度下通过轧制（冷轧）、拉拔、锻造（冷锻）等方式发生塑性变形，这不仅会导致永久的形状变化，还会增加强度并降低延展性由于加工硬化。 |
| Gear motor | 齿轮马达 |
Essentially a gear pump run in reverse, in which high-pressure fluid supplied to one side of the casing causes the gears to rotate. 本质上是一个齿轮泵反向运行，其中供应到外壳一侧的高压流体导致齿轮旋转。 |
| Centrifugal fan | 离心风机 |
A machine with a rotor consisting of a number of blades mounted around a hub and used for moving air or other gases. The gas enters the rotor axially and is discharged radially at increased pressure. 一种带有转子的机器，转子由安装在轮毂周围的许多叶片组成，用于移动空气或其他气体。气体轴向进入转子并在增加的压力下径向排出。 |
| Weight (W) (Unit N) | 重量（W）（单位：N） |
The force of attraction on a body due to gravity. A body’s weight is the product of its mass and the gravitational field strength at that point. Mass remains constant, but weight depends on the object’s position on the Earth’s surface, decreasing with increasing altitude. If g is the acceleration due to gravity, the weight of a mass m is given by W = mg. On Earth, the acceleration due to gravity is approximately 9.81 m/s², so that the weight of a 1 kg mass is 9.81 N. More generally, the weight is the force exerted on the mass of a body when in the gravitational field of another body. 重力由于重力作用在物体上的吸引力。物体的重量是其质量和该点引力场强度的乘积。质量保持不变，但重量取决于物体在地球表面的位置，随着海拔的升高而减小。如果g是重力引起的加速度，则质量m的重量由W=mg给出。在地球上，重力引起的加速度约为9.81m/s²，因此1千克质量的重量为9.81N。更一般地说，重量是在另一个物体的重力场中施加在物体质量上的力。 |
| Wheel | 轮 |
A solid disc, or a circular ring with spokes radiating from a central hub, either attached to an axle around which it revolves or which revolves with a rotating axle. 一个实心圆盘，或一个带有辐条的圆环，辐条从一个中心毂放射出来，或附在一个绕其旋转的轴上，或与一个旋转轴一起旋转。 |
| Acceleration-error constant | 加速度误差常数 |
When the reference (demand) input to a control system is parabolic, the output signal will also be parabolic in steady state. The signal that is constant in this situation is the acceleration and thus for a parabolic input the steady-state error, referred to as the acceleration-error constant, is the error in the acceleration. 当控制系统的参考（需求）输入是抛物线时，输出信号在稳定状态下也将是抛物线。在这种情况下恒定的信号是加速度，因此对于抛物线输入，称为加速度误差常数的稳态误差是加速度中的误差。 |
| Width across flats | 平面宽度 |
A principal dimension of nuts, or of bolt heads. Work hardening The slight increase in hardness and strength produced when a body is loaded past its yield point. Also called strain hardening. 螺母或螺栓头的主要尺寸。加工硬化：当物体被加载超过其屈服点时，硬度和强度略有增加。也称为应变硬化。 |
| Critical strain | 临界应变 |
The strain just sufficient to cause recrystallization; because the strain is small, usually only a few percent, recrystallization takes place from only a few nuclei, which produces a recrystallized structure consisting of very large grains. 刚好足以引起再结晶的应变；由于应变很小，通常只有百分之几，再结晶只发生在少数核上，从而产生由非常大的晶粒组成的再结晶结构。 |
| Full-size fastener | 全尺寸紧固件 |
Finished fastener with a shank diameter of ds ≈ d or ds > d, or screw threaded to the head, or fully threaded stud. 柄径为ds≈d或ds>d的紧固件，或螺纹连接到头部，或全螺纹螺柱。 |
| 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。 |
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