| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Stress relieving | 应力消除 |
Heating to a suitable temperature, holding long enough to reduce residual stresses, and then cooling slowly enough to minimize the development of new residual stresses. 加热到合适的温度，保持足够长的时间以减少残余应力，然后缓慢冷却以尽量减少新残余应力的产生。 |
| Wing | 翼 |
A relatively long and thin body with a cross section designed to produce lift when there is motion relative to a fluid. The principal applications are to aircraft and highperformance motor vehicles. 一种相对长而薄的物体，其横截面设计用于在相对于流体运动时产生升力。主要应用于飞机和高性能机动车辆。 |
| Axial load (Unit N) | 轴向载荷（单位N） |
In general, a tensile or compressive load directed along the axis of a component. Strictly the load should pass through the centroid of the cross section to avoid inducing bending moments and be perpendicular to the plane of the section. 通常，沿部件的轴定向的拉伸或压缩载荷。严格来说，载荷应通过横截面的质心以避免产生弯矩并垂直于横截面。 |
| Starting friction | 起动摩擦 |
(limiting friction, static friction, stiction) (Unit N) The force required to initiate movement between two bodies in contact. （极限摩擦力、静摩擦力、粘滞）（单位N）在两个接触物体之间启动运动所需的力。 |
| Bearing strain | 轴承应变 |
The ratio of the deformation of the bearing hole, in the direction of the applied force, to the pin diameter in a bearing test. 轴承孔在作用力方向上的变形与轴承测试中销直径的比值。 |
| 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。 |
| Working section | 工作区 |
That part of a wind tunnel in which models are placed for testing, or where detailed measurements are performed. 风洞中放置模型进行测试或进行详细测量的部分。 |
| 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。 |
| 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。 |
| Coefficient of restitution (e) | 回弹系数（e） |
The ratio of the relative velocity of two colliding bodies after collision to that before. In perfectly elastic collisions e = 1; when all the impact energy is dissipated, e = 0. 两个碰撞体在碰撞后与碰撞前的相对速度之比。在完全弹性碰撞中e=1；当所有的冲击能量都消散时，e=0。 |
| Hydrogen-induced delayed cracking | 氢致延迟开裂 |
A term sometimes used to identify a form of hydrogen embrittlement in which a metal appears to fracture spontaneously under a steady stress less than the yield stress. There is usually a delay between the application of stress (or exposure of the stressed metal to hydrogen) and the onset of cracking. Also referred to as static fatigue. 有时用于识别一种氢脆形式的术语，其中金属在小于屈服应力的稳定应力下似乎会自发断裂。在施加应力（或将受应力金属暴露于氢）与开裂开始之间通常存在延迟。也称为静态疲劳。 |
| Scleroscope hardness number (HSc or HSd) | 硬化镜硬度值（HSc或HSd） |
A number related to the height of rebound of a diamond-tipped hammer dropped on the material being tested. It is measured on a scale determined by dividing into 100 units the average rebound of the hammer from a quenched(to maximum hardness) and untempered AISI W5 tool steel test block. 与落在被测材料上的菱形锤的回弹高度相关的数字。通过将锤子从淬火（达到最大硬度）和未淬火的AISI W5工具钢试块上的平均回弹分为100个单位来测量。 |
| Work ratio | 工作比 |
The ratio of the net work out to the actual work out for a thermodynamic cycle. 热力学循环的净功与实际功之比。 |
| Serrations | 锯齿 |
A row of notches or tooth-like projections on an edge or surface. On an engineering drawing, serrations on the surface of a circular component are shown over about 60° of arc. 边缘或表面上的一排凹口或齿状突起。在工程图纸上，圆形部件表面的锯齿超过约60°的圆弧。 |
| Hot shortness | 热脆性 |
The reduction of ductility in steels at high temperatures caused by melting of sulfides that wet grain boundaries and spread along them. 高温下钢的延展性降低，这是由于硫化物的熔化润湿晶界并沿晶界扩散而引起的。 |
| Cohesive zone | 凝聚力区 |
In fracture-mechanics modelling and simulation, the region at the crack tip over which an assumed traction (load-displacement) relation has to be overcome to permit initiation and propagation of a crack. 在断裂力学建模和模拟中，必须克服假定的牵引（载荷-位移）关系以允许裂纹萌生和扩展的裂纹尖端区域。 |
| Bimetallic strip | 双金属片 |
A strip formed by welding, riveting or brazing together two metals having different coefficients of expansion, which causes the strip to curl when its temperature changes. Typical combinations are steel and copper or steel and brass. 将两种膨胀系数不同的金属焊接、铆接或钎焊在一起形成的带材，当温度变化时，带材会卷曲。典型的组合是钢和铜或钢和黄铜。 |
| 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。 |
| Concentrated load | 集中负荷 |
A load on a component which is distributed over a very small area, idealized as the line load of a wedge or knife edge, and the point load of a cone. 分布在非常小的区域上的部件上的载荷，理想化为楔形或刀刃的线载荷和锥体的点载荷。 |
| 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。 |
| Angle of friction | 摩擦角 |
(friction angle, β) (Unit °) For a body in contact with a plane surface, the angle between the normal to the surface and the resultant force between the body and the surface. If the friction force is F and normal force is N, β is given by F/N = μ = tan β where μ is the coefficient of friction. （摩擦角，β）（单位°）对于与平面接触的物体，表面法线与物体与表面之间的合力之间的夹角。如果摩擦力为F，法向力为N，则β由F/N=μ=tanβ给出，其中μ是摩擦系数。 |
| 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。 |
| Cementite | 渗碳体 |
A compound of iron and carbon, known chemically as iron carbide and having the approximate chemical formula Fe3C. It is characterized by an orthorhombic crystal structure. When it occurs as a phase in steel, the chemical composition will be altered by the presence of manganese and other carbide-forming elements. 碳化铁一种铁和碳的化合物，化学上称为碳化铁，化学式近似为Fe3C。其特征在于正交晶体结构。当它在钢中以相形式出现时，锰和其他碳化物形成元素的存在将改变其化学成分。 |
| 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。 |
| Machine | 机器 |
A mechanism that transmits power in the performance of a useful task. More than one machine in one place, either connected or performing separate functions, is termed machinery. 在执行有用任务时传递能量的机制。一个地方有一台以上的连接或执行单独的功能，称为机器。 |
| Dynamics | 动力学 |
The branch of mechanics that deals with objects in motion. Its two main branches are kinematics, which studies motion without regards to its cause, and kinetics, which also takes into account forces that cause motion. 力学中研究运动物体的分支。它的两个主要分支是运动学和动力学，前者研究运动而不考虑其原因，后者也考虑引起运动的力。 |
| Range of stress (Sr) | 应力范围（Sr） |
The algebraic difference between the maximum and minimum stress in one cycle—that is, Sr = Smax – Smin 一个循环中最大和最小应力之间的代数差，即Sr=Smax–Smin |
| Two-stroke engine | 二冲程发动机 |
(two-cycle engine) A petrol or diesel engine in which an air/fuel charge is introduced through an induction port, compressed and burned, expanded and then exhausted through an exhaust port. The two ports in the cylinder wall are opened and closed by the piston. There are two strokes in each revolution of the crankshaft. In total-loss lubrication petrol engines, the lubricating oil is mixed with the fuel. （双循环发动机）一种汽油或柴油发动机，其中空气/燃料通过进气口引入，压缩和燃烧，膨胀，然后通过排气口排出。气缸壁上的两个口由活塞打开和关闭。曲轴每转一圈有两个冲程。在全失润滑汽油发动机中，润滑油与燃油混合。 |
| 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。 |
| Batch | 一批 |
A definite quantity of some product or material produced under conditions that are considered uniform. A batch is usually smaller than a lot. 在被认为是均匀的条件下生产的一定数量的某些产品或材料。批次通常小于很多。 |
| Junker machine | 容克机 |
A test machine, first proposed by Gerhard Junker, for testing the vibration resistance of fasteners. 由Gerhard Junker首次提出的测试机，用于测试紧固件的抗振性。 |
| Gearbox | 变速箱 |
A mechanism consisting of meshing gears which transmit power and torque to an output shaft from an input shaft directly connected to an engine. The mechanism is normally contained within a casing filled with lubricating oil. The diagram shows a simple four-speed sliding-mesh gearbox in which gears with different numbers of teeth are slid along parallel splined shafts within the gearbox to mesh with each other and change the ratio of output to input speed (gear ratio). 一种由啮合齿轮组成的机构，将动力和扭矩从直接连接到发动机的输入轴传递到输出轴。该机构通常包含在充满润滑油的外壳内。示例一个简单的四速滑动啮合齿轮箱，其中具有不同齿数的齿轮沿着齿轮箱内的平行花键轴滑动，以相互啮合并改变输出与输入速度的比率（齿轮比）。 |
| 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。 |
| Stead’s brittleness | 斯特德脆性 |
A condition of brittleness that causes transcrystalline fracture in the coarse grain structure that results from prolonged annealing of thin sheets of low-carbon steel previously rolled at a temperature below about 705 °C (1300 °F). The fracture usually occurs at about 45° to the direction of rolling. 一种脆性状态，导致粗晶结构中发生穿晶断裂，这是由于之前在低于约705°C（1300°F）的温度下轧制的低碳钢薄板经过长时间退火造成的。断裂通常发生在与轧制方向约45°处。 |
| Dilatometer | 膨胀计 |
An instrument for measuring length or volume changes in a solid during heating and subsequent cooling or isothermal holding. · An instrument for measuring the linear expansion or contraction in a metal resulting from changes in such factors as temperature and allotropy. 一种在加热和随后的冷却或等温保持过程中测量固体长度或体积变化，测量金属因温度和同素异形体等因素的变化而引起的线性膨胀或收缩的仪器。 |
| Mass flow meter | 质量流量计 |
An instrument, such as a Coriolis flow meter, which measures the mass flow rate of a fluid flowing through a pipe or other duct, rather than its volume flow rate. 一种仪器，例如科里奥利流量计，一种测量流经管道或其他管道的流体的质量流率而不是其体积流率的仪器。 |
| Compression test | 压缩测试 |
A method for assessing the ability of a material to withstand compressive loads. The determination of the stress–strain curve of a material by axial loading of a specimen in compression. In brittle materials failure is in the elastic range; more ductile materials will yield before fracture; very ductile materials will plastically deform extensively before failure. The compression strength (compressive strength), with unit Pa, is the compressive stress that causes failure in a component or structure. 一种评估材料承受压缩载荷能力的方法。通过压缩试样的轴向载荷确定材料的应力-应变曲线。在脆性材料中，破坏在弹性范围内；韧性更强的材料在断裂前会屈服；韧性很强的材料在失效前会发生广泛的塑性变形。抗压强度（抗压强度），单位为Pa，是导致部件或结构失效的压应力。 |
| 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。 |
| Ductile | 延展性材料 |
(ductile material) Describes a material that can be deformed permanently to large strains without fracture. If a bolt can be stretched well past its yield point before breaking, it is said to be ductile. （延展性材料）描述一种可以永久变形到大应变而不断裂的材料。如果螺栓在断裂前可以很好地拉伸超过其屈服点，则称其具有延展性。 |
| Induction hardening | 感应淬火 |
A surface-hardening process in which only the surface layer of a suitable ferrous workpiece is heated by electromagnetic induction to above the upper critical temperature and immediately quenched. 一种表面硬化工艺，在该工艺中，只有合适的含铁工件的表面层通过电磁感应加热到高于上临界温度，并立即淬火。 |
| Steam gauge | 汽压表 |
A pressure gauge used to measure gauge pressure in a line, boiler, cylinder, or other device operating with steam. 一种压力表，用于测量管道、锅炉、汽缸或其他与蒸汽一起工作的装置中的表压。 |
| 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。 |
| Crack-extension force (G) | 裂纹扩展力（G） |
The elastic energy per unit of new separation area that would be made available at the front of an ideal crack in an elastic solid during a virtual increment of forward crack extension. 在向前裂纹扩展的虚拟增量期间，在弹性固体中理想裂纹的前端可获得的每单位新分离面积的弹性能量。 |
| Alloy | 合金 |
1. A metallic material composed of two or more elements, one of which is usually a metal to which the other elements are added, e.g. iron-carbon or aluminium-copper (binary alloy); nickel-chromium-iron (ternary alloy). 2. A plastic produced as a blend of two or more immiscible polymers. This results in material that cannot be achieved by polymerization. 1.由两种或多种元素组成的金属材料，其中一种通常是添加了其他元素的金属，例如铁碳或铝铜（二元合金）；镍铬铁（三元合金）。2.由两种或多种不混溶聚合物混合而成的塑料。这导致无法通过聚合获得的材料。 |
| 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。 |
| Depth (Unit m) | 深度（单位米） |
1. The vertical distance below a datum surface, especially the sea surface. 2. The distance between the top and bottom of a hole, step in a surface, or a container. 1.基准面以下的垂直距离，尤其是海面。2. 孔的顶部和底部之间的距离、表面上的台阶或容器中的距离。 |
| Tensiometer | 张力计 |
An instrument used to measure surface tension. 用来测量表面张力的仪器。 |
| Grain size | 晶粒大小 |
A measure of the areas or volumes of grains in a polycrystalline metal, usually expressed as an average when the individual sizes are fairly uniform. In metals containing two or more phases, the grain size refers to that of the matrix unless otherwise specified. For metals, a measure of the areas or volumes of grains in a polycrystalline material, usually expressed as an average when the individual sizes are fairly uniform. In metals containing two or more phases, the grain size refers to that of the matrix unless otherwise specified. Grain sizes are reported in terms of number of grains per unit area or volume, average diameter, or as a grainsize number derived from area measurements. 多晶金属中晶粒的面积或体积的量度，通常表示为单个尺寸相当均匀时的平均值。在含有两相或多相的金属中，除非另有说明，晶粒尺寸是指基体的晶粒尺寸。多晶材料中晶粒的面积或体积的量度，通常表示为单个尺寸相当均匀时的平均值。在含有两相或多相的金属中，除非另有说明，晶粒尺寸是指基体的晶粒尺寸。晶粒尺寸以每单位面积或体积的晶粒数、平均直径或从面积测量得出的晶粒尺寸数来报告。 |
| Isothermal annealing | 等温退火 |
Austenitizing a ferrous alloy and then cooling to and holding at a temperature at which austenite transforms to a relatively soft ferrite carbide aggregate. 将铁合金奥氏体化，然后冷却至奥氏体转变为相对软的铁素体碳化物集合体的温度并保持该温度。 |
| 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。 |
| Thermochemical treatment | 热化学处理 |
Heat treatment carried out in a medium suitably chosen to produce a change in the chemical composition of the object by exchange with the medium. 在适当选择的介质中进行热处理，以通过与介质交换产生物体化学成分的变化。 |
| Vent | 发泄 |
A small valve that allows the release of pressurized fluid from a pipe, pressure vessel, etc., often to the atmosphere. 一种小阀门，允许将加压流体从管道、压力容器等中释放到大气中。 |
| 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。 |
| Radian (rad) | 弧度（rad） |
A coherent derived SI unit defined as the plane angle subtended at the centre of a circle by an arc having a length equal to the radius. Thus 2π radians are equivalent to 360° and 1 rad ≈ 57.3°. 一种相干导出的国际单位制单位，定义为在圆心处被长度等于半径的弧对向的平面角。因此，2π弧度相当于360°和1弧度≈57.3°. |
| 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。 |
| Kiln | 窑 |
An industrial oven for burning, baking, or drying. 用于燃烧、烘烤或干燥的工业烤箱。 |
| Mechanical properties of solid materials | 固体材料的力学性能 |
The strength and stiffness properties of solid materials such as fracture toughness, the moduli of elasticity, percent elongation, 固体材料的强度和刚度特性，例如断裂韧性、弹性模量、伸长率、 |
| Screw feeder | 螺旋给料机 |
A mechanism for handling bulk materials in which a rotating helicoidal screw moves the material axially forward. Similar to a screw conveyor, but required to discharge material at a controlled rate very accurately. It operates with the screw completely full. 一种用于处理散装物料的机构，其中旋转的螺旋螺杆使物料轴向向前移动。类似于螺旋输送机，但需要以受控速率非常精确地排出物料。它在螺杆完全充满的情况下运行。 |
| 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。 |
| Zirconia-toughened alumina composites | 氧化锆增韧氧化铝复合材料 |
(ZTA composites) Ceramic composites based on aluminium oxide to which zirconium oxide is added, resulting in improved fracture toughness. （ZTA复合材料）基于氧化铝的陶瓷复合材料，其中添加了氧化锆，从而提高了断裂韧性。 |
| Union (union joint) | 活接头 |
A threaded pipe fitting that allows two pipes to be connected anddetached without the need for either to be rotated, and without damaging the pipe ends. 一种螺纹管件，允许连接和拆卸两个管道，而无需旋转任何一个管道，且不会损坏管道端部。 |
| Morse taper | 莫氏锥度 |
A self holding, standard taper largely used on drilling tools, drilling machine spindles, and some lathes. 一种自持式标准锥度，主要用于钻孔工具、钻床主轴和一些车床。 |
| Absolute pressure | 绝对压力 |
1. The pressure measured relative to zero pressure (vacuum). 2. Gage pressure plus barometric pressure in the same units. 1.相对于零压力（真空）测量的压力。2.表压加上大气压力的单位相同。 |
| Turbine | 涡轮 |
A turbomachine in which a rotor (turbine wheel) or impeller is caused to rotate and convert flow energy into shaft power or thrust. 转子（涡轮）或叶轮旋转并将流动能量转换为轴功率或推力的涡轮机。 |
| Thermodynamics laws | 热力学定律 |
The zeroth, first, second, and third laws of thermodynamics. 热力学第零、第一、第二和第三定律。 |
| Biomechanics | 生物力学 |
The application of mechanical-engineering principles, including thermodynamics, fluid mechanics, and solid mechanics together with materials engineering, to biological systems. 机械工程原理（包括热力学、流体力学和固体力学以及材料工程）在生物系统中的应用。 |
| 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。 |
| 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。 |
| Anneal to temper | 退火回火 |
A final partial anneal that softens a cold worked nonferrous alloy to a specified level of hardness or tensile strength. 将冷加工的有色金属合金软化到规定的硬度或抗拉强度水平的最终局部退火。 |
| Absolute stability | 绝对稳定 |
Condtion of a linear system in which there exists a limiting value of the open-loop gain such that the system is stable for all lower values of that gain, and unstable for all higher values. 线性系统的条件，其中存在开环增益的限制值，使得系统对于该增益的所有较低值都是稳定的，而对于所有较高值来说都是不稳定的。 |
| Twist | 扭转 |
The helix produced in a cylindrical component, such as a shaft, wire, tensioned cable, or rope, when one end is rotated relative to the other. Measured either as the number of turns per unit length, or by the helix angle (twist angle). 当一端相对于另一端旋转时，在圆柱形部件（如轴、钢丝、张紧电缆或绳索）中产生的螺旋。以每单位长度的圈数或螺旋角（扭曲角）测量。 |
| Dimensioning | 尺寸标注 |
The specification on an engineering drawing of the size (e.g. length, radius, angle, or spacing) and the relative location (e.g. angular position) of each feature of a component. The numerical values often include the tolerances. There should be no more dimensions than are necessary to manufacture the component. 工程图纸上对部件每个特征的尺寸（例如长度、半径、角度或间距）和相对位置（例如角位置）的规范。数值通常包括公差。尺寸不应超过制造组件所需的尺寸。 |
| Pressure-relief valve | 减压阀 |
A valve that limits the maximum pressure in a pressure vessel or fluid-power system to a specified level. 将压力容器或流体动力系统中的最大压力限制在规定水平的阀门。 |
| Working load (Unit N) | 工作负荷（单位：N） |
The tension in a bolt in use; tension produced by a combination of Residual preload and a portion (usually) of any External load. The Joint diagram is usually used to predict the approximate working load a fastener will see in service. The load under which a component or structure is designed to operate under normal conditions. 螺栓在使用中的张力；残余预载荷和部分（通常）任何外部载荷的组合产生的张力。连接图通常用于预测紧固件在使用中的近似工作载荷。部件或结构设计为在正常条件下运行的荷载。 |
| Critical temperature | 临界温度 |
(1) Synonymous with critical point if the pressure is constant. (2) The temperature above which the vapor phase cannot be condensed to liquid by an increase in pressure. （1） 如果压力恒定，则与临界点同义。（2） 高于该温度时，气相不能通过压力升高而冷凝为液体。 |
| 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。 |
| Supercooling | 过冷 |
Cooling below the temperature at which an equilibrium phase transformation can take place, without actually obtaining the transformation. 在没有实际获得相变的情况下，冷却到可以发生平衡相变的温度以下。 |
| Size dimension (Unit m) | 尺寸范围（单位：米） |
The specified value of a diameter, length, width, etc. of a feature required to specify the finished form of a component or assembly. 指定部件或组件的成品形状所需的特征的直径、长度、宽度等的指定值。 |
| Bearing failure | 轴承故障 |
A failure that occurs in a riveted or bolted joint when the transverse load divided by the bearing area results in a stress that leads to permanent plastic deformation. 当横向载荷除以承载面积产生导致永久塑性变形的应力时，铆接或螺栓连接中发生的失效。 |
| Crack size (a) | 裂纹尺寸（a） |
A lineal measure of a principal planar dimension of a crack. This measure is commonly used in the calculation of quantities descriptive of the stress and displacement fields. In practice, the value of crack size is obtained from procedures for measurement of physical crack size, original crack size, or effective crack size, as appropriate to the situation under consideration. 裂纹主平面尺寸的线性度量。这种测量通常用于计算描述应力场和位移场的量。在实践中，裂纹尺寸的值是通过测量物理裂纹尺寸、原始裂纹尺寸或有效裂纹尺寸的程序获得的，视情况而定。 |
| Free carbon | 游离碳 |
The part of the total carbon in steel or cast iron that is present in elemental form as graphite or temper carbon. Contrast with combined carbon. 钢或铸铁中总碳中以石墨或回火碳等元素形式存在的部分。与结合碳形成对比。 |
| Stress cracking | 应力开裂 |
A family of failure modes, each of which involves high stress and chemical action. The family includes Hydrogen embrittlement, Stress corrosion cracking, stress embrittlement, and hydrogen-assisted stress corrosion. 一系列失效模式，每种模式都涉及高应力和化学作用。该系列包括氢脆、应力腐蚀开裂、应力脆化和氢辅助应力腐蚀。 |
| 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。 |
| Tribology | 摩擦学 |
The science and technology concerned with interacting surfaces in relative motion. 与相对运动中相互作用的表面有关的科学和技术。 |
| Swept volume (Unit m³) | 扫描体（单位m³) |
In the cylinder of a piston engine or other device, the volume between top and bottom dead centre positions of a piston; equal to πR2S where R is the piston radius and S is the stroke. 在活塞发动机或其他装置的气缸中，活塞上止点和下止点位置之间的体积；等于πR2S，其中R是活塞半径，S是冲程。 |
| Gamma iron | 加马铁 |
The face-centered cubic form of pure iron, stable from 910 to 1400 °C (1670 to 2550 °F). 纯铁的面心立方形式，在910至1400°C（1670 2550°F）温度范围内稳定。 |
| Shear strain rate(Unit 1/s) | 剪切应变率（单位1/s） |
In the deformation of solids, the rate at which shear strain is applied in a test or changes with time in a loaded component or structure. 在固体变形中，在试验中施加剪切应变的速率，或在加载部件或结构中随时间变化的速率。 |
| Root diameter (Unit m) | 根部直径（单位：m） |
The diameter of the circle passing through the roots of teeth in gear teeth or screw threads. 穿过齿轮齿或螺纹中齿根的圆的直径。 |
| Positive-displacement machine | 正排量机 |
A machine that incorporates pistons, valves, etc. to ensure positive admission and delivery of a working fluid and prevent undesired reversal of flow. This class of machine incorporates all reciprocating compressors and expanders and some types of rotary compressor, the Roots blower, agear pump, a lobe pump, and a vane pump. 包含活塞、阀门等的机器，以确保工作流体的正向进入和输送，并防止不期望的反向流动。这类机器包括所有往复式压缩机和膨胀机以及一些类型的旋转压缩机、罗茨鼓风机、抽水机、凸轮泵和叶片泵。 |
| Maximum stress-intensity factor (Kmax) | 最大应力强度因子（Kmax） |
The maximum value of the stress-intensity factorin a fatigue cycle. 疲劳循环中应力强度因子的最大值。 |
| Toggle (toggle clamp) | 拨动（拨动夹） |
A device consisting of two pinned levers that are almost in line between two end points in the same plane. Bringing the levers into line generates large forces between the ends. Used to obtain a large mechanical advantage or as a locking mechanism. 由两个销杆组成的装置，在同一平面的两个端点之间几乎成一条直线。将杠杆对齐会在端部之间产生较大的力。用于获得较大的机械优势或用作锁定机构。 |
| 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）。 |
| 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。 |
| Critical point | 临界点 |
(1) The temperature or pressure at which a change in crystal structure, phase or physical properties occurs. Same as transformation temperature. (2) In an equilibrium diagram, that specific value of composition, temperature and pressure, or combinations thereof, at which the phases of a heterogeneous system are in equilibrium. （1） 晶体结构、相或物理性质发生变化的温度或压力。与转变温度相同。（2） 在平衡图中，指组成、温度和压力或其组合的特定值，在该值下，多相体系的相处于平衡状态。 |
| Cleavage | 分裂 |
The tendency of a material to cleave or split along definite crystallographic planes. 材料沿特定晶面劈裂或分裂的趋势。 |
| Liquid carburizing | 液体渗碳 |
Surface hardening of steel by immersion into a molten bath consisting of cyanides and other salts. 通过浸入由氰化物和其他盐组成的熔池中对钢进行表面硬化。 |
| Scatter | 分散 |
Data points or calculations are said to be scattered when they are not all the same. A ‘‘lot of scatter in preload’’ means wide variation in the preloads found in individual bolts. 当数据点或计算不尽相同时，它们被称为分散的。“预载的大量分散”意味着单个螺栓中的预载差异很大。 |
| 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。 |
| Proof stress | 弹性极限应力 |
(1) The stress that will cause a specified small permanent set in a material. (2) A specified stress to be applied to a member or structure to indicate its ability to withstand service loads. （1）在材料中引起规定的小永久变形的应力。（2）施加在构件或结构上的规定应力，以表明其承受工作荷载的能力。 |
| 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。 |
| Concurrent engineering | 并行工程 |
The integration of the procedures for product design, material selection and manufacturing method to include life-cycle analysis. 产品设计、材料选择和制造方法程序的整合，包括生命周期分析。 |
| 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。 |
| Compression failure | 压缩失败 |
The reduction or removal of a component’s load-bearing capacity in compression, caused by buckling, fracture, crease formation in fibre composites, etc. 由纤维复合材料中的屈曲、断裂、折痕形成等引起的部件在压缩中的承载能力的降低或消除。 |
| Compression member | 压缩构件 |
A structural component, the major loading on which is compressive. 一种结构部件，其上的主要载荷是压缩的。 |
| Rotary piston flow meter | 旋转活塞流量计 |
A rotary liquid flow meter in which a cylindrical rotor, eccentrically mounted within a cylindrical casing, the axes of the two cylinders being parallel, is caused to rotate by the liquid flow. The flow rate is determined from the number of rotations of the rotor in a given time. 一种旋转式液体流量计，其中偏心安装在圆柱形外壳内的圆柱形转子，两个圆柱体的轴线平行，由液体流引起旋转。流量由转子在给定时间内的转数确定。 |
| Translational joint | 平移铰 |
A robot joint where the controlled variable is straight line movement. 控制变量为直线运动的机器人关节。 |
| Shoulder screw | 轴肩螺钉 |
A screw having two or more diameters or shoulders and commonly used for supporting levers and other machine parts that have to operate freely. 一种具有两个或两个以上直径或轴肩的螺钉，通常用于支撑杠杆和其他必须自由操作的机器部件。 |
| 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。 |
| Pitch angle (Unit °) | 俯仰角（单位°） |
For a bevel gear, the angle between the axis and the pitch-cone generator. 对于锥齿轮，轴与节锥生成器之间的角度。 |
| 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。 |
| Constant-mesh gearbox | 恒啮合齿轮箱 |
A gearbox in which the pairs of gears giving different speed ratios are constantly in mesh, different ratios being obtained by connecting or disconnecting the relevant gear to the driving shaft. 一种齿轮箱，其中提供不同速比的齿轮对始终啮合，通过将相关齿轮连接或断开驱动轴获得不同的速比。 |
| U-tube | U型管 |
A device consisting of two vertical tubes connected at either the top or bottom by a length of tubing such that a U-shape is formed. 由两个垂直管组成的装置，在顶部或底部通过一段管子连接，形成U形。 |
| Springback | 回弹 |
The extent to which metal tends to return to its original shape or contour after undergoing a forming operation. 金属在经历成形操作后趋于恢复其原始形状或轮廓的程度。 |
| Crack length (depth) (a) | 裂纹长度（深度）（a） |
In fatigue and stress corrosion cracking, the physical crack size used to determine the crack growth rate and the stress-intensity factor. For the compact-type specimen, crack length is measured from the line connecting the bearing points of load application. For the center-cracked-tension specimen, crack length is measured from the perpendicular bisector of the central crack. 在疲劳和应力腐蚀裂纹中，用于确定裂纹扩展速率和应力强度因子的物理裂纹尺寸。对于紧凑型试样，裂纹长度从连接载荷施加点的线开始测量。对于中心裂纹拉伸试样，从中心裂纹的垂直平分线测量裂纹长度。 |
| Austenite-stabilizer | 奥氏体稳定剂 |
Alloying element expanding the γ-phase field in the corresponding phase diagram, which manifests itself in a decrease of the A3 temperature and an increase of the A4 temperature in binary alloys Fe–M as well as in a decrease of A1 temperature in ternary alloys Fe–C–M (M is an alloying element). The solubility of austenite-stabilizers in ferrite is much lower than in austenite. Under the influence of austenite-stabilizers, austenite can become thermodynamically stable down to room temperature. 合金元素扩展了相应相图中的γ相场，这表现为二元合金Fe-M中A3温度的降低和A4温度的升高，以及A1温度的降低三元合金Fe–C–M（M是合金元素）。奥氏体稳定剂在铁素体中的溶解度远低于在奥氏体中的溶解度。在奥氏体稳定剂的影响下，奥氏体可以在低至室温时变得热力学稳定。 |
| Age hardening | 时效硬化 |
Raising the strength and hardness of an alloy by heating a supersaturated solid solution at a relatively low temperature to induce precipitation of a finely dispersed second phase. Also known as aging or precipitation hardening. Hardening by aging, usually after rapid cooling or cold working. 通过在相对较低的温度下加热过饱和固溶体以诱导细分散的第二相沉淀来提高合金的强度和硬度。也称为时效或沉淀硬化。通常在快速冷却或冷加工后。 |
| 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。 |
| Breaking load (Unit N) | 断裂负荷（单位N） |
The load applied at some point to a component or structure which leads to fracture. The breaking stress (breaking strength) is the average stress at which a member breaks, given by the breaking load divided by the area over which it acts. 在某个点施加到导致断裂的部件或结构的载荷。断裂应力（断裂强度）是构件断裂时的平均应力，由断裂载荷除以其作用的面积给出。 |
| Lubricant | 润滑剂 |
Any substance interposed between two surfaces for the purpose of reducing the friction or wear between them. 为了减少两个表面之间的摩擦或磨损而置于两个表面间的任何物质。 |
| Major diameter | 螺纹大径 |
On a straight thread, the diameter of the imaginary cylinder that just touches the crest of an external thread or the root of an internal thread. 在直螺纹上，仅接触外螺纹顶部或内螺纹根部的假想圆柱体的直径。 |
| Coil spring | 螺旋弹簧 |
A spiral (‘clockwork’) or helical (cylindrical) spring. A spring steel wire wound in a spiral pattern. 螺旋（“发条”）或螺旋（圆柱形）弹簧。以螺旋状缠绕的弹簧钢丝。 |
| Flame annealing | 火焰退火 |
Annealing in which the heat is applied directly by a flame. 通过火焰直接加热的退火。 |
| Nonlinear behavior | 非线性行为 |
A fastener or joint system is said to exhibit nonlinear behavior when the relationship between the External load on the joint and deformation of the parts is nonlinear, or when the relationship between increasing Preload and deformation is nonlinear. 当接头上的外部载荷与零件变形之间的关系是非线性的，或者当增加的预载荷与变形之间的联系是非线性的时，可以说紧固件或接头系统表现出非线性行为。 |
| Pop rivet | 拉钉 |
A hollow rivet that enables a connexion to be made from one side only of an assembly. 一种空心铆钉，使连接只能从组件的一侧进行。 |
| Torsion-bar suspension | 扭杆悬架 |
A type of motor-vehicle suspension in which one end of a torsion bar is rigidly fixed to the chassis while the other carries a lever to which are attached the components that carry a wheel. In a torsion-beam suspension, a beam connects the wheels on either side of the vehicle. 一种汽车悬架，其中扭力杆的一端刚性固定在底盘上，而另一端带有一个杠杆，杠杆上连接着承载车轮的部件。在扭转梁悬架中，梁连接车辆两侧的车轮。 |
| Grain growth | 晶粒生长 |
An increase in the average size of the grains in polycrystalline metal, usually as a result of heating at elevated temperature. 多晶金属中晶粒平均尺寸的增加，通常是高温加热的结果。 |
| Selective quenching | 局部淬火 |
Quenching only certain portions of an object. 仅淬火工件的某些部分。 |
| International Practical Temperature Scale (IPTS) | 国际实用温标（IPTS） |
A close approximation to the thermodynamic temperature scale based upon the triple points of hydrogen (13.8 K), neon (24.6 K), oxygen (54.4 K), argon (83.8 K), mercury (234.3 K), and water (273.2 K); the melting point of gallium (302.9 K); and the freezing points of indium (429.7 K), tin (505.1 K), zinc (692.7 K), aluminium (933.5 K), silver (1 234.9 K), gold (1 337.3 K), and copper (1 基于氢（13.8K）、氖（24.6K）、氧（54.4K）、氩（83.8K），汞（234.3K）和水（273.2K）的三相点的热力学温度标度的近似值；镓的熔点（302.9K）；铟（429.7K）、锡（505.1K）、锌（692.7K），铝（933.5K）、银（1234.9K）、金（1337.3K）和铜等。 |
| Dew point analyzer | 露点分析仪 |
An atmosphere monitoring device that measures the partial pressure of water vapor in an atmosphere. 一种大气监测装置，用于测量大气中水蒸气的分压。 |
| Allotropy | 同素异形体 |
A near synonym for polymorphism. Allotropy is generally restricted to describing polymorphic behavior in elements, terminal phases, and alloys whose behavior closely parallels that of the predominant constituent element. 多态性的近义词。同素异形体通常仅限于描述元素、终端相和合金中的多晶型行为，其行为与主要组成元素的行为非常相似。 |
| Hot dipping | 热浸 |
(hot-dip galvanizing) A process of coating an iron, steel, or aluminium object with a thin layer of zinc by passing it through a bath of molten zinc at a temperature of about 460°C. （热浸镀锌）通过使铁、钢或铝物体通过温度约为460°C的熔融锌浴，在铁、钢或铝物体上镀上一层薄薄的锌层的工艺。 |
| Engine | 引擎 |
A machine that converts energy, including the chemical energy in a fuel and electrical energy, into mechanical energy, usually to produce power delivered through a rotating shaft or thrust. Examples include internal-combustion engines, gas and steam turbines, rocket engines, electric, hydraulic and pneumatic motors. 一种将能量（包括燃料中的化学能和电能）转换为机械能的机器，通常通过旋转轴或推力产生动力。例子包括内燃机、燃气轮机和蒸汽轮机、火箭发动机、电动、液压和气动马达。 |
| Semi-rotary pump | 半回转泵 |
A form of self-priming pump, often hand-operated, suitable for pumping water and light oils such as diesel oil and petrol. As shown in the diagram, liquid is sucked into one side of the pump through flap valves and simultaneously ejected from the other side on one stroke. The sequence is reversed on each successive stroke. 一种自吸泵，通常是手动的，适用于泵送水和轻油，如柴油和汽油。液体通过翻板阀吸入泵的一侧，同时在一个冲程中从另一侧排出。在每个连续冲程上，顺序颠倒。 |
| 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。 |
| Cavitation tunnel | 空泡试验筒 |
A closed-circuit recirculating water tunnel in which the static pressure can be reduced to sufficiently low levels for cavitation studies to be performed. 一种闭路循环水隧洞，其中静压可降至足够低的水平，以便进行气蚀研究。 |
| Hardenability | 淬透性 |
Defined as the ability of a ferrous material to acquire hardness after austenitization and quenching. The relative ability of a ferrous alloy to form martensite when quenched from a temperature above the upper critical temperature. Hardenability is commonly measured as the distance below a quenched surface where the metal exhibits a specific hardness (50 HRC, for example) or a specific percentage of martensite in the microstructure. 定义为黑色金属材料在奥氏体化和淬火后获得硬度的能力。铁合金从高于上临界温度的温度淬火时形成马氏体的相对能力。淬透性通常以淬火表面下方的距离来测量，金属在淬火表面处表现出特定硬度（例如50HRC）或微观结构中马氏体的特定百分比。 |
| Load | 负载 |
For testing machines, a force applied to a test piece that is measured in units such as pound-force, newton, or kilogram-force. 对于试验机，施加在试件上的力，以磅力、牛顿或千克力等单位测量。 |
| Combustible | 易燃 |
(inflammable) A term for substances that can be ignited and burned. （易燃）可点燃和燃烧的物质的术语。 |
| Fretting fatigue | 微动疲劳 |
Fatigue fracture that initiate at a surface area where fretting has occurred. The progressive damage to a solid surface that arises from fretting. 在发生微动的表面区域开始的疲劳断裂。由微动引起的对固体表面的渐进性损坏。 |
| Coefficient of rolling friction | 滚动摩擦系数 |
The ratio of force parallel to a surface, on which an object rolls, to the normal force. Unlike sliding friction, rolling friction depends on the size of the contact patch and the radius of the rolling element, and the behaviour depends on whether the contact is elastic, viscoelastic, or plastic and on hysteresis losses. 平行于物体滚动表面的力与法向力之比。与滑动摩擦不同，滚动摩擦取决于接触片的大小和滚动元件的半径，其行为取决于接触是弹性的、粘弹性的还是塑性的以及滞后损失。 |
| Partial annealing | 不完全退火 |
An imprecise term used to denote a treatment given cold-worked material to reduce the strength to a controlled level or to effect stress relief. To be meaningful, the type of material, the degree of cold work, and the time-temperature schedule must be stated. 一个不精确的术语，用于表示冷加工材料的处理，以将强度降低到受控水平或消除应力。为了有意义，必须说明材料类型、冷加工程度和时间-温度计划。 |
| Linear (tensile or compressive) strain | 线性（拉伸或压缩）应变 |
The change per unit length due to force in an original linear dimension. An increase in length is considered positive. 由于原始线性尺寸中的力，每单位长度的变化。长度的增加被认为是正的。 |
| Breaking stress | 断裂应力 |
The stress at failure. Also known as rupture stress. 失效时的应力。也称为破裂应力。 |
| Alpha iron | 阿尔法铁 |
The body-centered cubic form of pure iron, stable below 910 °C (1670 °F). 纯铁的体心立方形式，在910°C(1670°F)以下稳定。 |
| Countersinking | 埋头孔 |
The flaring out of the rim of a drilled hole to form a truncated conical depression to receive a screw having a conical head, thus giving a flush fitting. 从钻孔的边缘向外张开以形成截锥形凹陷，以容纳具有锥形头的螺钉，从而提供齐平的配件。 |
| Tension joint | 张力接头 |
A joint which is primarily subjected to loads acting more or less parallel to the axes of the bolts. 主要承受或多或少平行于螺栓轴线的载荷的接头。 |
| Hypoeutectic alloy | 亚共晶合金 |
In an alloy system exhibiting a eutectic, any alloy whose composition has an excess of base metal compared with the eutectic composition, and whose equilibrium microstructure contains some eutectic structure. 在呈现共晶的合金系统中，其成分比共晶成分多的任何合金，其平衡微观结构包含一些共晶结构。 |
| Water-jet cutting | 水射流切割 |
Cutting of materials such as rock by means of a high-speed jet of water containing abrasive particles. 通过含有磨料颗粒的高速水射流切割岩石等材料。 |
| Rubber hardness | 橡胶硬度 |
The indentation hardness of rubber-like materials in which the depth of indentation under load is measured. This is a measure of elastic moduli rather than yield stress as with ductile materials, since there is little, if any, permanent impression remaining on unloading rubbery materials. 测量负载下压痕深度的橡胶类材料的压痕硬度。这是对弹性模量的测量，而不是对韧性材料的屈服应力，因为卸载橡胶材料时几乎没有（如果有的话）永久压痕。 |
| Threading machine | 螺纹机 |
A machine used to cut an external thread on a rod, tube, bolt blank, etc. or an internal thread in a hole, tube, nut blank, etc. 用于切割杆、管、螺栓毛坯等上的外螺纹或孔、管、螺母毛坯等中的内螺纹的机器。 |
| Shoulder | 轴肩 |
The portion of a shaft, stepped component, or flanged component, where a change in diameter or other dimension occurs. Even for a nominal step change, in practice there will be a radius where shoulder and shaft meet in order to avoid too severe a stress concentration. 轴、阶梯部件或法兰部件的直径或其他尺寸发生变化的部分。即使是名义阶跃变化，在实践中，肩部和轴相交处也会有一个半径，以避免出现过严重的应力集中。 |
| Fog quenching | 雾淬 |
Quenching in a fine vapor or mist. 在细蒸汽或薄雾中淬火。 |
| PSI (pounds per square inch) | PSI（磅/平方英寸） |
Pressure measurement. Psia (pounds per square inch absolute) measures actual pressure with no allowance for atmospheric pressure. Psig (pounds per square inch gauge) measures pressure with the gauge set to zero (0) at atmospheric pressure (14.7 psia). In other words psig = psia – 14.7. 压力测量。Psia（绝对磅/平方英寸）测量实际压力，不考虑大气压力。Psig（磅/平方英寸表压）在大气压（14.7 psia）下，将表压设置为零（0）时测量压力。换句话说，psig=psia–14.7。 |
| 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。 |
| Acoustics | 声学 |
The science and engineering of sound; its production, propagation, control, interaction with materials, etc. 声音科学与工程；它的产生、传播、控制、与材料的相互作用等。 |
| Load and resistance factor design | 负载和阻力系数设计 |
A design procedure developed for the AISC by the Research Council on Structural Connections. Assigns uncertainties in the strength of (i.e., resistance of) and in the service loads to be placed on a shear joint to estimate the probable strength of the joint. It is a recently defined alternative to the Allowable stress design procedure. 结构连接研究委员会为AISC制定的设计程序。分配剪切接头的强度（即阻力）和工作荷载的不确定性，以估计接头的可能强度。它是最近定义的容许应力设计程序的替代方案。 |
| Pressure control valve | 压力控制阀 |
A valve used to set the pressure level in a pressure vessel or piping system. 用于设置压力容器或管道系统中压力水平的阀门。 |
| Ultrasonic method | 超声波法 |
Measuring elongation uses a sound pulse, generated at one end of a bolt, that travels the length of a bolt, bounces off the far end, and returns to the sound generator in a measured period of time. 测量伸长使用在螺栓一端产生的声音脉冲，该脉冲沿螺栓长度传播，从远端反弹，并在测量的时间段内返回到声音发生器。 |
| Scragging machine | 刮擦机 |
1. A machine to test springs by impulsive loading 2. A machine to increase the service life of coil springs by compressing them to their minimum solid length before use, thereby inducing favourable residual stresses. 1.一种通过冲击载荷测试弹簧的机器2.一种在使用前将螺旋弹簧压缩至其最小实心长度以提高其使用寿命的机器，从而产生有利的残余应力。 |
| 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。 |
| Shear joint | 剪切接头 |
A joint which is subjected primarily to loads acting more or less perpendicular to the axes of the bolts. 主要承受或多或少垂直于螺栓轴线的载荷的接头。 |
| Impact wrench | 冲击扳手 |
An air- or electric-powered wrench in which multiple blows from tiny hammers are used to produce output torque to tighten fasteners. A pneumatically-or electrically-powered socket wrench used to tighten or loosen nuts through the application of torque in a rapid series of impulses. 一种气动或电动扳手，使用小锤子多次敲击来产生输出扭矩以拧紧紧固件，用于通过在一系列快速脉冲中施加扭矩来拧紧或松开螺母。 |
| Cooling stresses | 冷却应力 |
Residual stresses resulting from nonuniform distribution of temperature during cooling. 冷却过程中温度分布不均匀导致的残余应力。 |
| 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。 |
| Shear strength (Unit Pa) | 抗剪强度（单位Pa） |
The maximum shear stress that can be withstood by a material either (a) before plasticity occurs or (b) before rupture. 材料在（a）塑性发生之前或（b）断裂之前能够承受的最大剪切应力。 |
| 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。 |
| Normality | 常态 |
The principle that the vector sum of plastic strain increments is perpendicular to the yield surface. 塑性应变增量矢量和垂直于屈服面的原理。 |
| Total carbon | 总碳 |
The sum of the free and combined carbon (including carbon in solution) in a ferrous alloy. 铁合金中游离碳和结合碳（包括溶液中的碳）的总和。 |
| 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。 |
| Cavitation | 空蚀空化 |
The formation of vapour- or gas-filled cavities in a liquid due to reduction of the local pressure, often due to acceleration of the fluid, such as in flow through a convergent nozzle. If there is no dissolved gas in the liquid, vaporous cavitation occurs when the pressure falls below the saturated vapour pressure. If the bubbles are formed due to high temperature, the process is termed boiling. If there is dissolved gas, gaseous cavitation occurs due to pressure reduction, temperature increase, or diffusion (degassing). At the tips of marine propellers and in hydraulic machinery, the collapse of cavitation bubbles can cause noise and vibration and lead to surface damage in the form of pitting. 由于局部压力降低而在液体中形成充满蒸汽或气体的空腔，通常原因是流体的加速，例如收敛喷嘴的流动。如果液体中没有溶解气体，当压力降至饱和蒸汽压力以下时，会发生蒸汽空化。如果气泡是由于高温形成的，则该过程称为沸腾。如果存在溶解气体，则由于压力降低、温度升高或扩散（脱气），会发生气穴。在船用螺旋桨尖端和液压机械中，空化气泡的破裂可能会引起噪音和振动，并导致以点蚀形式出现的表面损坏。 |
| 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。 |
| Torsional stress | 扭转应力 |
The shear stress on a transverse cross section resulting from a twisting action. 扭转作用在横截面上产生的剪切应力。 |
| Electroplating | 电镀 |
Deposition of one metal on to another using electrolysis. The metal to be plated forms the cathode in an electrolytic cell, and the metal to be deposited forms the anode. 使用电解将一种金属沉积到另一种金属上。待镀金属形成电解池中的阴极，待沉积金属形成阳极。 |
| 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。 |
| Biaxial stress | 双轴应力 |
Generalized loading of a body in a single plane with no loading normal to it. 物体在一个平面内的广义载荷，没有垂直于它的载荷。 |
| 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。 |
| Horizontal batch furnace | 卧式间歇炉 |
A versatile batch-type furnace that can give light or deep case depths, and because the parts are not exposed to air, horizontal batch furnaces can give surfaces almost entirely free of oxides. 一种多功能间歇式炉，可以提供浅或深的外壳深度，并且由于零件不暴露在空气中，卧式间歇式炉可以使表面几乎完全没有氧化物。 |
| Q-factor | 品质因素 |
(quality factor, sharpness of resonance) A non-dimensional parameter that describes, for a given resonant mode, the sharpness of the peak in the frequency response of a lightly-damped linear oscillator: Q = ωRES/Δω where ωRES is the resonance frequency and Δω is the half-power bandwidth of the resonance. It is inversely related to the damping such that a broad peak corresponds to high damping and a narrow peak to low damping. （品质因数，共振尖锐度）一个无量纲参数，用于描述给定共振模式下，轻阻尼线性振荡器频率响应峰值的尖锐度：Q=ωRES/Δω，其中ωRES是共振频率，Δω是共振的半功率带宽。它与阻尼成反比，因此宽峰值对应于高阻尼，窄峰值对应于低阻尼。 |
| Tap wrench | 螺丝攻扳手 |
A lever with an adjustable square hole at its centre into which is fitted the shank of a tap so that torque can be applied to cut a thread. 一种杠杆，其中心有一个可调节的方孔，丝锥柄安装在该孔中，以便施加扭矩以切断螺纹。 |
| 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。 |
| Actual power | 实际功率 |
(actual horsepower) (Unit W or hp) The power delivered at the output shaft of an engine, before subsequent transmission through a gearbox etc. （实际马力）（单位W或hp）在随后通过变速箱等传输之前，在发动机输出轴上传递的功率。 |
| 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。 |
| Maximum load (Pmax) | 最大负载（Pmax） |
(1) The load having the highest algebraic value in the load cycle. Tensile loads are considered positive and compressive loads negative. (2)Used to determine the strength of a structural member; the load that can be borne before failure is apparent. （1）负载循环中具有最高代数值的负载。拉伸荷载视为正荷载，压缩荷载视为负荷载。（2）用于确定结构构件的强度；失效前可承受的载荷是明显的。 |
| Machine screw | 机械螺丝 |
A countersunk, slotted screw with machined threads such as are found on bolts. A relatively small screw, usually less than 20 mm in diameter, with the thread running along the whole length up to the head, intended to be screwed into threaded holes. If inserted through plain holes in assembled parts and held together by a nut, an undesirable contact surface of threads bearing against the surface of a hole results. 带有机加工螺纹的沉头开槽螺钉，如螺栓上的螺纹。一种相对较小的螺钉，直径通常小于20毫米，螺纹沿整个长度一直延伸到头部，用于拧入螺纹孔中。如果通过装配零件上的平孔插入并用螺母固定在一起，则会导致螺纹与孔表面接触不良。 |
| Vacuum servo | 真空服务器 |
A vacuum-operated servomotor which is used in a motor vehicle to provide a brake effort greater than the capability of the driver. 一种真空操作的伺服电机，用于机动车中，以提供大于驾驶员能力的制动力。 |
| Caustic cracking | 苛性开裂 |
A form of stress-corrosion cracking most frequently encountered in carbon steels or iron-chromiumnickel alloys that are exposed to concentrated hydroxide solutions at temperatures of 200 to 250 °C (400 to 480 °F). Also known as caustic embrittlement. 在200至250°C（400至480°F）的温度下暴露于浓氢氧化物溶液中的碳钢或铁铬镍合金中最常遇到的一种应力腐蚀开裂形式。也称为碱脆。 |
| Black oxide | 黑色氧化物 |
A black finish on a metal produced by immersing it in hot oxidizing salts or salt solutions. 通过将金属浸入热氧化盐或盐溶液中产生的黑色饰面。 |
| Nut factor | 螺母系数 |
An experimental constant used to evaluate or describe the ratio between the torque applied to a fastener and the Preload achieved as a result. 用于评估或描述施加在紧固件上的扭矩与由此获得的预载之间的比率的实验常数。 |
| Blue brittleness | 蓝色脆性 |
Anomalous loss of ductility when quenched steels are tempered in the range 250–350°C (temperatures that produce blue tints on the surface of components). Brittleness exhibited by some steels after being heated to some temperature within the range of about 205 to 370 °C (400 to 700 °F), particularly if the steel is worked at the elevated temperature. Killed steels are virtually free of this kind of brittleness. 当淬火钢在250–350°C范围内回火（在部件表面产生蓝色色调的温度）时，延展性异常损失。某些钢在加热到约205至370°C（400至700°F）范围内的某个温度后表现出脆性，特别是在高温下加工钢时。镇静钢几乎没有这种脆性。 |
| Mechanical efficiency (η) | 机械效率（η） |
1. In general for a machine, the ratio of output work to input work. 2. For a compressor, the ratio of indicated power to shaft power; for a reciprocating engine or an expander, the ratio of shaft power to indicated power. 1.一般而言，机器的输出功与输入功之比。2.对于压缩机，指示功率与轴功率之比；对于往复式发动机或膨胀机，轴功率与指示功率之比。 |
| Actuating system | 驱动系统 |
A system in which an electrical, pneumatic or hydraulic input supplied to an actuator produces force, torque, or displacement, usually in a controlled way. 一种系统，其中提供给执行器的电气、气动或液压输入通常以受控方式产生力、扭矩或位移。 |
| Cast steel | 铸钢 |
Steel that is cast into shapes. It has superior properties to most cast irons, but is more expensive to produce. 铸成形状的钢。与大多数铸铁相比，它具有优越的性能，但生产成本更高。 |
| 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。 |
| Unit | 单位 |
A numerical indication of the magnitude of a physical quantity. The basic units of mass, length, time, etc. are relative to agreed standards. 物理量大小的数字指示。质量、长度、时间等基本单位与商定的标准相对应。 |
| Notch strength | 缺口强度 |
The maximum load on a notched tensile-test specimen divided by the minimum cross-sectional area (the area at the root of the notch). Also known as notch tensile strength. 缺口拉伸试样上的最大载荷除以最小横截面积（缺口根部的面积）。也称为缺口抗拉强度。 |
| Acoustic power | 声功率 |
(sound power) (Unit W) The rate of flow of acoustic energy across a specified surface. （声功率）（单位W）声能流过指定表面的速率。 |
| Transmission dynamometer | 传动测功机 |
A dynamometer in which the power transmitted by a shaft is obtained from the product of its rotation speed and the torque determined from measured shear strains along the shaft. 一种测功机，其中轴传递的功率由其转速和扭矩的乘积获得，扭矩由沿轴测得的剪切应变确定。 |
| Dynamic coupling | 动态耦合 |
In vibrations, the existence of inertial terms depending on mass in the governing equations, so that there is only a force if there is a corresponding acceleration. 在振动中，惯性项的存在取决于控制方程中的质量，因此只有当有相应的加速度时才有力。 |
| 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。 |
| Failure of the bolt | 螺栓失效 |
Term implying that the bolt has broken or the threads have stripped. There can be many reasons for this. 表示螺栓断裂或螺纹脱落的术语。原因可能有很多种。 |
| Auxetic materials | 拉胀材料 |
Those man-made materials for which Poisson’s ratio is negative, so that the cross section expands when subjected to a longitudinal tensile stress and contracts when subjected to a longitudinal compressive stress. 泊松比为负的人造材料，其横截面在受到纵向拉应力时会膨胀，在受到纵向压应力时会收缩。 |
| Three-quarters hard | 四分之三硬度 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about midway between those of half hard and full hard tempers. 一种非铁合金和一些铁合金的回火，其特征是抗拉强度和硬度介于半硬回火和全硬回火之间。 |
| 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。 |
| 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。 |
| Fatigue life for p % survival | p%存活率的疲劳寿命 |
An estimate of the fatigue life that p% of the population would attain or exceed at a given stress level. The observed value of the median fatigue life estimates the fatigue life for 50% survival. Fatigue life for p% survival values, where p is any number, such as 95, 90, etc., may also be estimated from the individual fatigue life values. p%存活在给定应力水平下达到或超过的疲劳寿命估计值。中值疲劳寿命的观察值估计了50%存活率的疲劳寿命。p%存活值的疲劳寿命，其中p为任何数字，如95、90等，也可根据单个疲劳寿命值进行估算。 |
| Absolute temperature (Unit K) | 绝对温度（单位K） |
A temperature T measured relative to absolute zero, 0 K or −273.15°C, the lowest temperature achievable at which molecular motion vanishes so that a body would have zero heat energy. The kelvin is equal in magnitude to the degree Celsius (°C). The kelvin temperature scale (kelvin absolute temperature scale) is an absolute or thermodynamic temperature scale derived from the Celsius scale: T(K) = T(°C) + 273.15. The Rankine absolute scale is derived from the Fahrenheit scale such that T(R) = T(°F) + 459.67, i.e. a scale relative to 0 R or −459.67°F where R is the Rankine degree symbol and °F is the Fahrenheit symbol. 相对于绝对零、0K或0K测量的温度T−273.15°C，分子运动消失的最低温度，因此物体的热能为零。开尔文的大小等于摄氏度（℃）。开尔文温度标度（开尔文绝对温度标度）是从摄氏标度得出的绝对或热力学温度标度：T（K）=T（°C）+273.15。兰金绝对标度是从华氏标度得出，使得T（R）=T（°F）+459.67，即相对于0R或0R的标度−459.67°F，其中R是朗肯度符号，°F是华氏度符号。 |
| Combustion deposit | 燃烧沉积物 |
Ash, carbon, and other incombustible solids, often due to impurities in the fuel, that build up on any surfaces exposed to products of combustion. They can lead to corrosion, reduced heat transfer and so higher flue-gas temperatures and reduced efficiency. 灰、碳和其他不燃固体，通常是由于燃料中的杂质，在暴露于燃烧产物的任何表面上堆积。它们会导致腐蚀、传热降低，从而导致烟气温度升高和效率降低。 |
| Pressure gauge | 压力表 |
An instrument used to measure absolute or gauge pressure. The sensing element may be a tube which deflects when pressurized, as in a Bourdon gauge, a bellows as in an aneroid barometer, a piezoelectric crystal, a piezoresistive element, etc. 测量绝对压力或表压的仪器。传感元件可以是加压时会偏转的管，如波登压力表、无液气压计中的波纹管、压电晶体、压阻元件等。 |
| Condensate strainer | 冷凝水过滤器 |
A filter in a steam plant used to remove particulate matter from condensate before it is added to feedwater. 蒸汽设备中的过滤器，用于在将冷凝水添加到给水中之前去除冷凝水中的颗粒物。 |
| Controlled cooling | 控制冷却 |
Cooling from an elevated temperature in a predetermined manner, to avoid hardening, cracking, or internal damage, or to produce desired microstructure or mechanical properties. 以预定方式从升高的温度冷却，以避免硬化、开裂或内部损坏，或产生所需的微观结构或机械性能。 |
| Square | 正方 |
1. A regular quadrilateral, i.e. a polygon with four equal sides and four right angles. 2. An instrument to check angles of internal and external surfaces and flatness. 1.正四边形，即具有四条等边和四个直角的多边形。2.一种检查内外表面角度和平面度的仪器。 |
| Athermal transformation | 非热变化 |
A reaction that proceeds without benefit of thermal fluctuations; that is, thermal activation is not required. In contrast, a reaction that occurs at constant temperature is an isothermal transformation; thermal activation is necessary in this case and the reaction proceeds as a function of time. 在没有热波动的情况下进行的反应；也就是说，不需要热激活。相反，在恒温下发生的反应是等温转变。在这种情况下，热活化是必要的，并且反应作为时间的函数进行。 |
| Screw compressor | 螺杆压缩机 |
A positive-displacement rotary compressor in which gas is progressively compressed by two intermeshing, counter-rotating, helical screws. 一种容积式旋转压缩机，其中气体由两个相互啮合、反向旋转的螺旋螺杆逐渐压缩。 |
| Mole number (N) | 摩尔数（N） |
The number of moles in a given mass m of a substance, equal to m divided by the molar mass of the substance. 摩尔数物质给定质量m中的摩尔数，等于m除以物质的摩尔质量。 |
| Bánki turbine | 班基涡轮机 |
A cross-flow, impulse-type water turbine for very low heads in which a jet of water in the form of a flat sheet passes transversely through the turbine, so going through the runner twice. The thin runner blades which run horizontally across the turbine parallel to the axis of rotation are profiled in cross section. 一种用于非常低水头的横流脉冲式水轮机，其中平板形式的水射流横向穿过涡轮机，因此穿过转轮两次。平行于旋转轴水平穿过涡轮机的薄转轮叶片在横截面上具有轮廓。 |
| Radial load (Unit N) | 径向负荷（单位：N） |
1. Centrifugal loading induced in a rotating body. 2. (through-wallthickness load) The radial component of loading arising from internal or external pressurization of a closed vessel. There will also be axial and hoop loading. 1.旋转体中产生的离心载荷。2.（贯穿壁厚载荷）由封闭容器的内部或外部加压产生的载荷的径向分量。还存在轴向和环向载荷。 |
| Stress | 应力（单位Pa） |
The intensity of the internally distributed forces or components of forces that resist a change in the volume or shape of a material that is or has been subjected to external forces. Stress is expressed in force per unit area and is calculated on the basis of the original dimensions of the cross section of the specimen. Stress can be either direct (tension or compression)or shear. 1. Stress ‘at a point’ (i.e. over a volume of material that is very small compared with that of the component or structure) is the load per unit area for every face of an infinitesimal cube surrounding the point. 2. In fluid flow the stress tensor σij is the sum of an isotropic part −pδij, δij being the Kronecker delta, having the same form as the stress tensor for a fluid at rest, p being the static pressure, and the non-isotropic, deviatoric stress tensor dij which is due entirely to the fluid motion. 内部分布力或力分量的强度，这些力或力的分量抵抗正在或已经受到外力的材料的体积或形状的变化。应力以单位面积的力表示，并根据试样横截面的原始尺寸计算。应力可以是直接（拉伸或压缩）或剪切。1.“在一点”的应力（即在与组件或结构相比非常小的材料体积上）是围绕该点的无限小立方体的每个面的单位面积载荷。2. 在流体流动中，应力张量σij是各向同性部分-pδij的总和，δij是Kroneckerδ，具有与静止流体的应力张量相同的形式，p是静压，非各向同性, 偏应力张量 dij 完全由流体运动引起。 |
| Total elongation | 总伸长率 |
A total amount of permanent extension of a test piece broken in a tensile test. 拉伸试验中断裂试样的永久延伸总量。 |
| Rockwell superficial hardness test | 洛氏表面硬度试验 |
Same as Rockwell hardness test, except that smaller minor and major loads are used. 与洛氏硬度测试相同，只是使用较小的次要载荷和主要载荷。 |
| Impact energy (Unit J) | 冲击能量（单位J） |
The amount of energy required to fracture a material, usually measured by means of an Izod test or Charpy test.The type of specimen and test conditions affect the values and therefore should be specified. 1. The sum of the kinetic energies of all the bodies involved at the instant of collision of two or more moving bodies. 2. The energy required to fracture a specimen in a Charpy or Izod impact test. 使材料断裂所需的能量，通常通过悬臂梁式试验或夏比试验测量。试样类型和试验条件会影响数值，因此应加以说明。1.两个或多个运动物体碰撞瞬间所有物体的动能之和。2.夏比或悬臂冲击试验中断裂试样所需的能量。 |
| Cap screw | 帽螺钉 |
A bolt where the thread runs right up to the head and engages in a threaded hole or captive nut in an adjoining member. A finished screw 5mm or larger, used for fastening two pieces together by passing the screw through a clearance hole in one part and screwing in into a tapped hole in the other. A finished screw, used for fastening two pieces together by passing the screw through a clearance hole in one part and screwing it into a tapped hole in the other. Heads may be hexagon, round, flat, fillister or socket type. 一个5毫米或更大的螺钉，其螺纹一直延伸到头部，并与相邻构件的螺纹孔或外加螺母啮合,用于将两个部件固定在一起，方法是将螺钉穿过一个部分的间隙孔，然后拧入另一个部分的螺纹孔。头部可以是六角形、圆形、扁平形、圆角形或套筒形。 |
| Compressor blades | 压缩机叶片 |
The aerofoil-shaped vanes that form the rotor(s) and stator(s) of an axial-flow compressor. The aerodynamic design is more critical than is the case for turbine blades because there is an increase in pressure across each row of blades. The arrows in the diagram indicate the flow direction relative to the blades. 形成轴流式压缩机的转子和定子的翼型叶片。空气动力学设计比涡轮叶片的情况更为关键，因为每排叶片的压力都会增加。图中的箭头表示相对于叶片的流动方向。 |
| Olsen cup test | 奥尔森杯测试 |
A cupping test in which a piece of sheet metal, restrained except at the center, is deformed by a standard steel ball until fracture occurs. The height of the cup at time of fracture is a measure of the ductility. 一种杯突试验，其中一块金属板，除了中心以外，被一个标准钢球变形，直到发生断裂。断裂时杯的高度是延展性的量度。 |
| Compound pendulum | 复摆 |
A rigid body free to swing about an axis. 可绕轴自由摆动的刚体。 |
| Fastener | 紧固件 |
A fastener is a mechanical device for holding two or more bodies in definite positions with respect to each other. 紧固件是一种机械装置，用于将两个或多个物体相对于彼此固定在确定的位置。 |
| Hot strength (Unit Pa) | 热强度（单位Pa） |
The yield stress (or sometimes fracture stress) of a material at temperatures above about half its melting point in kelvins. 材料在高于其熔点一半（以开尔文为单位）的温度下的屈服应力（有时为断裂应力）。 |
| Creep–time relations | 蠕变时间关系 |
Algebraic or numerical relations between creep strain and time at constant stress. 恒定应力下蠕变应变与时间之间的代数或数值关系。 |
| Deposit gauge | 沉积量计 |
(deposition gauge) An instrument employed in air pollution studies for measuring the amount of pollutant deposited on a given area in a given time under given conditions. （沉降计）在空气污染研究中使用的仪器，用于测量在给定条件下在给定时间内沉积在给定区域上的污染物量。 |
| Coherent precipitate | 相干沉淀 |
A crystalline precipitate that forms from solid solution with an orientation that maintains continuity between the crystal lattice of the precipitate and the lattice of the matrix, usually accompanied by some strain in both lattices. Because the lattices fit at the interface between precipitate and matrix, there is no discernible phase boundary. 由固溶体形成的结晶沉淀物，其取向保持沉淀物晶格和基体晶格之间的连续性，通常伴随着两个晶格中的一些应变。由于晶格适合于沉淀和基体之间的界面，因此不存在可识别的相边界。 |
| Coaxial | 同轴 |
A term for components having a common axis such as concentric shafts. 具有共同轴线的部件的术语，例如同心轴。 |
| 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。 |
| Yield stress | 屈服应力 |
The stress level of highly ductile materials, such as structural steels, at which large strains take place without further increase in stress. 高韧性材料（如结构钢）的应力水平，在该应力水平下发生大应变而不会进一步增加。 |
| Car furnace | 车炉 |
A batch-type furnace using a car on rails to enter and leave the furnace area. Car furnaces are used for lower stress relieving ranges. 一种间歇式炉，使用轨道上的小车进出炉区。汽车炉用于较低的应力消除范围。 |
| Heat balance (heat budget) | 热平衡（热预算） |
An energy balance involving only heat transfer across the system boundary and the stored energy. 仅涉及跨系统边界的热传递和存储能量的能量平衡。 |
| 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。 |
| Galling | 磨损 |
An extreme form of adhesive wear, in which large chunks of one part stick to the mating part (during sliding contact). 一种极端形式的粘着磨损，其中一个零件的大块粘在配合零件上（在滑动接触期间）。 |
| Rotary valve (rotating valve) | 旋转阀 |
A cylindrical or conical plug in which there is a transverse hole through which fluid can flow when the hole is aligned with the adjacent piping. 一种圆柱形或锥形塞，其中有一个横向孔，当该孔与相邻管道对齐时，流体可通过该孔流动。 |
| Tensile strength (Unit Pa) | 抗拉强度（单位Pa） |
In tension testing, the ratio of maximum load to original cross-sectional area. Also known as ultimate strength. The resistance that a material offers to tensile stress. It is defined as the smallest tensile stress required to break the body. (ultimate strength, ultimate tensile strength, UTS, Rm, Rm) The nominal or engineering stress given by the maximum load in a tension test divided by the original cross-sectional area of the specimen. The maximum load could be the fracture load for a brittle material, but for a ductile material it is usually taken as the load at which necking begins, beyond which the load falls. 在拉伸试验中，最大载荷与原始横截面积之比。也称为极限强度。材料对拉伸应力的抵抗力。它被定义为破坏主体所需的最小拉伸应力。（极限强度、极限抗拉强度、UTS、Rm、Rm）拉伸试验中最大载荷除以试样原始横截面积得出的标称或工程应力。对于脆性材料，最大载荷可以是断裂载荷，但对于韧性材料，最大荷载通常被视为颈缩开始时的载荷，超过该载荷时，载荷下降。 |
| Available draught (Unit Pa) | 可用通风量（单位Pa） |
The reduced pressure of combustion gases in a furnace or boiler, either forced or due to the buoyancy of hot gases, which is used to draw in combustion air and remove products of combustion. 炉子或锅炉中燃烧气体的压力降低，无论是强制还是由于热气体的浮力，用于吸入燃烧空气并去除燃烧产物。 |
| True strain | 真应变 |
(1) The ratio of the change in dimension, resulting from a given load increment, to the magnitude of the dimension immediately prior to applying the load increment. (2) In a body subjected to axial force, the natural logarithm of the ratio of the gage length at the moment of observation to the original gage length. Also known as natural strain. Compare with engineering strain. （1）给定载荷增量导致的尺寸变化与施加载荷增量之前尺寸大小的比率。（2）在承受轴向力的物体中，观察时刻标距与原始标距之比的自然对数。也称为自然应变。与工程应变相比。 |
| Oldham coupling | 十字联轴节 |
(double-slider coupling) A device for connecting a pair of misaligned parallel shafts, on the end of each of which are flanges having diametral tenons (tongues) that engage with matching slots spaced at 90° in an intermediate disc. As the coupling rotates, the disc compensates for shaft offset by sliding along each tenon in turn. Low-friction surfaces are requisite and the disc is often made of a polymer. An alternative arrangement has the slots in the flanges and the tenons on the disc. （双滑块联轴器）一种连接一对未对准平行轴的装置，在每个平行轴的端部有法兰，法兰具有直径榫（舌），与中间盘中间隔90°的匹配槽接合。当联轴器旋转时，圆盘通过依次沿每个榫头滑动来补偿轴偏移。低摩擦表面是必需的，阀盘通常由聚合物制成。另一种布置方式是法兰上的槽和阀盘上的榫头。 |
| Transverse strain | 横向应变 |
Linear strain in a plane perpendicular to the loading axis of a specimen. 垂直于试样加载轴的平面内的线性应变。 |
| 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 |
| Spring | 弹簧 |
An elastic component which stores mechanical energy and exerts a force when deformed. The slope of the curve of applied force F to the deflexion of a spring x, dF/dx, is termed the spring rate or spring modulus k with unit N/m. For a linear spring, the F(x) curve is proportional and k is called the spring constant. An elastic device which yields under stress or pressure but returns to its original state or position when the stress or pressure is removed. 储存机械能并在变形时施加力的弹性部件。作用力F与弹簧x偏转的曲线斜率dF/dx称为弹簧率或弹簧模量k，单位为N/m。对于线性弹簧，F（x）曲线成比例，k称为弹簧常数。一种弹性装置，在应力或压力下屈服，但在应力和压力消除后恢复到其原始状态或位置。 |
| Spalling | 剥落 |
The separation of macroscopic particles from a surface in the form of flakes or chips. 以薄片或碎片形式从表面分离宏观颗粒。 |
| Pitch (Unit m) | 间距（单位：m） |
1. In a cascade of identical turbine or compressor blades, the distance between successive blades measured parallel to the leading edges. 2. For a screw thread, the distance between adjacent thread forms measured parallel to the thread axis. 3. For an aircraft, the vertical relationship between the nose and the horizon. The pitch axis is an axis in the plane of the wings of an aircraft, perpendicular to the centreline, about which the aircraft rotates. Pitch motion is the corresponding up or down movement of the aircraft nose. Pitch attitude is the angle between the centreline of an aircraft and the horizontal. The angle is positive when the nose is above its position when the centreline is horizontal. 1.在相同涡轮或压缩机叶片的叶栅中，平行于前缘测量的连续叶片之间的距离。2.对于螺纹，平行于螺纹轴线测量的相邻螺纹形状之间的距离。3.对于飞机，机头和水平线之间的垂直关系。俯仰轴是飞机机翼平面内垂直于中心线的轴，飞机绕中心线旋转。俯仰运动是飞机机头的相应向上或向下运动。俯仰姿态是飞机中心线与水平线之间的角度。当中心线水平时，当机头高于其位置时，角度为正。 |
| Computer-aided design (CAD) | 计算机辅助设计（CAD） |
Generally, design and calculations performed by computer; more specifically, the use of computer graphics and models to communicate design concepts. Computer-aided design and computer-aided manufacturing (CAD/CAM) is where component dimensions resulting from CAD are passed by electronic means directly to machines for manufacture. 一般由计算机进行设计和计算，更具体地说，使用计算机图形和模型来传达设计概念。计算机辅助设计和计算机辅助制造（CAD/CAM）是由CAD产生的组件尺寸通过电子方式直接传递到机器进行制造。 |
| Structural-integrity analysis | 结构完整性分析 |
Assessment of components and structures for likelihood of failure by buckling, fracture, yielding, etc. under conditions of normal and accident loading. 在正常和事故荷载条件下，评估部件和结构因屈曲、断裂、屈服等而失效的可能性。 |
| 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。 |
| Radial wave equation | 径向波动方程 |
A differential equation describing the transmission of a wave in a system with radial symmetry. 描述波在径向对称系统中传输的微分方程。 |
| Hot hardness | 热硬度 |
The hardness of materials at high temperatures, often used to rank the performance of cutting tools. 材料在高温下的硬度，常用来对刀具的性能进行排名。 |
| Effective length of a bolt | 螺栓的有效长度 |
The grip length plus some portion of the bolt (often one-half of the thickness of the nuts) which lies within the nut(s) plus some portion (often one-half the thickness) of the head. 握持长度加上位于螺母内的螺栓的某些部分（通常是螺母厚度的二分之一）加上头部的某些部分（通常是厚度的二分之一）。 |
| 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。 |
| Mode of failure | 故障模式 |
The various ways in which a material can fail when subjected to loading, surface damage, chemical attack, heating, cooling, or radiation, in either isolation or combination. The failure modes include fracture, fatigue, creep, corrosion, erosion, and embrittlement. 材料在受到载荷、表面损伤、化学侵蚀、加热、冷却或辐射时，可能发生失效的各种方式，无论是单独还是组合。失效模式包括断裂、疲劳、蠕变、腐蚀、侵蚀和脆化。 |
| 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。 |
| Resistance thermometer | 电阻温度计 |
A thermometer in which the sensing element is basically a metal wire, usually of platinum, for which the variation of resistance with temperature is known accurately. A resistance pyrometer is a resistance thermometer intended for use up to about 1 000°C. 一种温度计，其中传感元件基本上是一根金属线，通常是铂，可以准确地知道电阻随温度的变化。电阻高温计是一种电阻温度计，用于高达约1000°C的温度。 |
| Composite property | 复合属性 |
In thermodynamics, a property defined in terms of the properties of a closed system and its surroundings, such as the non-flow exergy function. 在热力学中，根据封闭系统及其周围环境的性质定义的性质，例如非流动火用函数。 |
| Elongation | 伸张率 |
A term used in mechanical testing to describe the amount of extension of a test piece when stressed. 机械测试中使用的术语，用于描述试样在受力时的延伸量。 |
| Time quenching | 时间淬火 |
A term used to describe a quench in which the cooling rate of the part being quenched must be changed abruptly at some time during the cooling cycle. 用于描述淬火的术语，其中被淬火零件的冷却速率必须在冷却循环的某个时间突然改变。 |
| Repeatability | 重复性 |
A term used to refer to the test-result variability associated with a limited set of specifically defined sources of variability within a single laboratory. 一个术语，用于指与单个实验室内一组有限的特定变异源相关的测试结果变异性。 |
| Avogadro constant | 阿伏伽德罗常数 |
(Avogadro number, NA) A fundamental physical constant with the fixed numerical value 6.022 140 76 × 1023 mol−1. The mole contains exactly this number of elementary entities. A minor adjustment to the value of the Avogadro constant was made effective on 20 May 2019. （阿伏伽德罗数，NA）一个固定数值为6.02214076×1023mol的基本物理常数−摩尔正好包含这个数量的基本实体。对阿伏伽德罗常数值的微小调整于2019年5月20日生效。 |
| 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）。 |
| Nanoparticles | 纳米颗粒 |
Particles with dimensions of order 1 nm which have either been introduced into microstructures for reinforcement or are present as impurities. 尺寸为1nm级的颗粒，其已被引入微结构中用于增强或作为杂质存在。 |
| Bernoulli’s law | 伯努利定律 |
For a steadily flowing fluid (liquid or gas), the sum of the pressure, kinetic energy per unit volume and potential energy per unit volume is constant at any point in the fluid. Using this relationship, it is possible to measure the velocity of a fluid by measuring its pressure at two points, as with a manometer or Pitot tube. 对于稳定流动的流体（液体或气体），压力、每单位体积的动能和每单位体积的势能之和在流体中的任何点都是恒定的。使用这种关系，可以通过在两个点测量流体的压力来测量流体的速度，就像使用压力计或皮托管一样。 |
| Slant fracture | 倾斜裂缝 |
A type of fracture appearance, typical of plane-stress fractures, in which the plane of metal separation is inclined at an angle (usually about 45°) to the axis of the applied stress. 一种断裂现象，典型的平面应力断裂，其中金属分离面与施加应力的轴成一定角度（通常约45°）倾斜。 |
| Acoustic pyrometer | 声学高温计 |
A non-intrusive pyrometer based on the principle that the sound speed in a gas is proportional to the square root of its absolute temperature. 一种非侵入式高温计，其原理是气体中的声速与其绝对温度的平方根成正比。 |
| British Standards Institution (BSI) | 英国标准协会（BSI） |
The Institution in the UK responsible for the preparation and publication of standard specifications (British standards) for manufactured goods, their design, manufacture and testing. 负责为制成品及其设计、制造和测试制定和发布标准规范（英国标准）的英国机构。 |
| Preload | 预载 |
The tension created in a threaded fastener when the nut is first tightened. Often used interchangeably, but incorrectly, with Working load or bolt force or bolt tension 第一次拧紧螺母时螺纹紧固件中产生的张力。经常与工作载荷或螺栓力或螺栓张力互换使用但容易使用不当。 |
| Standard | 标准 |
(standard specification) A set of specifications for components, machines, materials, or processes intended to achieve uniformity, efficiency, and a specified quality. In the UK, standards issued by the British Standards Institution (BSI) are now generally those of the International Organization for Standardization (ISO). （标准规范）为实现一致性、效率和特定质量而制定的一套组件、机器、材料或工艺规范。在英国，英国标准协会（BSI）发布的标准现在基本上是国际标准化组织（ISO）的标准。 |
| Crank angle (Unit °) | 曲柄角度（单位°） |
The angle between the crank of a slider-crank mechanism and a line from the crankshaft centreline to the piston axis. 曲柄滑块机构的曲柄与曲轴中心线到活塞轴线的直线之间的角度。 |
| Offset | 偏移 |
The distance along the strain coordinate between the initial portion of a stress-strain curve and a line parallel to the initial portion that intersects the stress-strain curve at a value of stress (commonly 0.2%) that is used as a measure of the yield strength. Used for materials that have no obvious yield point. 应力-应变曲线的初始部分与平行于初始部分的线之间沿应变坐标的距离，该线以应力值（通常为0.2%）与应力-变形曲线相交，该应力值用作屈服强度的度量。用于没有明显屈服点的材料。 |
| Hydrogen embrittlement | 氢脆 |
A condition of low toughness, low ductility or cracking in metals resulting from the absorption of hydrogen. A common and troublesome form of Stress cracking. Several theories have been proposed to explain hydrogen embrittlement, but, at present, the exact mechanism is still unknown. What is known, however, is the fact that if hydrogen is trapped in a bolt by poor electroplating practices, it can encourage stress cracking. Bolts can fail, suddenly and unexpectedly, under normal loads. Premature crack growth over time under tensile stress leading to unexpected failure in certain metals, caused by small amounts of hydrogen in the microstructure. Hydrogen may enter steels during melting or heat treating, or during processes such as electroplating. 因吸收氢而导致金属韧性低、延展性低或开裂的情况，是一种常见且麻烦的应力开裂形式。在拉伸应力下，裂纹随时间过早扩展，导致某些金属发生意外失效，这是由微观结构中的少量氢引起的。在熔化或热处理过程中，或在电镀等过程中，氢可能进入钢中。已经提出了几种理论来解释氢脆，但目前，确切的机理仍然未知。已知的事实是，如果氢因电镀不当而被困在螺栓中，则会导致应力开裂。在正常载荷下，螺栓可能突然意外失效。 |
| Grain-boundary liquation | 晶界液化 |
An advanced stage of overheating in which material in the region of austenitic grain boundaries melts. 奥氏体晶界区域的材料熔化的过热阶段。 |
| 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。 |
| Dynamic load (Unit N) | 动态负载（单位N） |
1. Loading of a component or structure by a moving object whose point of application changes with time, e.g. the live load of a train passing over a bridge. 2. A load applied to a particular part of a component or structure in a short time interval. 1. 应用点随时间变化的移动物体对部件或结构的加载，例如通过桥梁的火车的活荷载。2. 在短时间内施加到部件或结构的特定部分的载荷。 |
| Torsion test | 扭力测试 |
A test designed to provide data for the calculation of the shear modulus, modulus of rupture in torsion, and yield strength in shear. 为计算剪切模量、扭转断裂模量和剪切屈服强度而设计的试验。 |
| Brake lining | 制动衬片 |
The replaceable friction material that covers a brake shoe in an internally expanding brake. 在内膨胀制动器中覆盖制动的可更换摩擦材料。 |
| 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。 |
| Initial stress | 初始应力 |
The stress produced by strain in a specimen immediately on achieving the given constant-strain conditions in a stress-relaxation test before stress-relaxation occurs. Sometimes referred to as instantaneous stress. 在应力松弛发生之前，在应力松弛试验中达到给定的恒定应变条件时，试样立即应变所产生的应力。有时称为瞬时压力。 |
| Pulley | 带轮 |
A free or driven wheel on a shaft with an appropriately shaped rim to carry a flat belt, vee belt, notched belt, rope, or chain. Used to transmit power or motion. 轴上的自由轮或从动轮，具有适当形状的轮缘，以承载平皮带、V形皮带、槽口皮带、绳索或链条。用于传递动力或运动。 |
| Bearing stress | 承受应力 |
The force per unit of bearing area. 每单位承载面积的力。 |
| 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。 |
| ANSI | ANSI |
The acronym for American National Standards Institute. 美国国家标准协会的缩写。 |
| Calorie | 卡路里 |
(cal, gram calorie, small calorie) An obsolete (i.e. non-SI) unit of energy equal to 4.186 8 J. It is the amount of energy needed to raise the temperature of 1 gram of pure airfree water from 14.5°C to 15.5°C at standard atmospheric pressure. （卡，克热量，小热量）一种已被淘汰的（即非SI）能量单位，等于4.1868J。它是在标准大气压力下将1克纯无空气水的温度从14.5℃升高到15.5℃所需的能量。 |
| 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。 |
| Scratch hardness | 划痕硬度 |
The resistance of a material, such as a metal, alloy, plastic, or mineral, to scratching by a much harder indenter, such as a diamond stylus, moved slowly across the surface. The scratch hardness number is computed from the loads and the dimensions of the residual scratch. 一种材料（如金属、合金、塑料或矿物）对更硬的压头（如金刚石触针）划伤的抵抗力，在表面上缓慢移动。根据载荷和残余划痕的尺寸计算划痕硬度值。 |
| Ultrasonic extensometer | 超声波伸长计 |
An electronic instrument which measures the change in length of a fastener ultrasonically as, or before and after, the fastener is tightened. 一种电子仪器，可在紧固件拧紧时或前后通过超声波测量紧固件长度的变化。 |
| Lockbolt | 锁紧螺栓 |
A fastener which bears a superficial resemblance to a bolt, but which engages a collar (instead of a nut) with annular grooves (instead of threads). The collar is swaged over the grooves on the male fastener to develop preload. 表面上类似于螺栓的紧固件，但与环槽（而不是螺纹）接合的轴环（而不是螺母）。套环在阳紧固件上的凹槽上锻造，以产生预紧力。 |
| Atomic volume | 原子体积 |
Volume of unit cell per atom. 每个原子的晶胞体积。 |
| Safe working load (Unit N) | 安全工作负荷（单位：N） |
The steady or unsteady load against which a component or structure is designed for normal operation. It is lower than that which would cause failure by buckling, fracture, or yielding, so as to accommodate uncertainty, possible fault or accident conditions. 部件或结构设计用于正常运行的稳定或不稳定荷载。该值低于因屈曲、断裂或屈服而导致失效的值，以适应不确定性、可能的故障或事故条件。 |
| Fastener with reduced shank | 短柄紧固件 |
Finished fastener with a shank diameter of ds ≈ d2. 柄径为ds≈d2的紧固件。 |
| Oxidative wear | 氧化磨损 |
A type of wear resulting from the sliding action between two metallic components that generates oxide films on the metal surfaces. These oxide films prevent the formation of a metallic bond between the sliding surfaces, resulting in fine wear debris and low wear rates. 由两个金属部件之间的滑动作用导致的一种磨损，在金属表面上产生氧化膜。这些氧化膜防止在滑动表面之间形成金属结合，导致细磨屑和低磨损率。 |
| Apparent area of contact | 表观接触面积 |
In tribology, the area of contact between two solid surfaces defined by the boundaries of their macroscopic interface. 在摩擦学中，两个固体表面之间的接触区域由其宏观界面的边界定义。 |
| Vapour–pressure curve | 蒸汽压力曲线 |
For a pure substance, the curve of saturation pressure plotted vs saturation temperature. 对于纯物质，绘制了饱和压力与饱和温度的曲线。 |
| 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。 |
| Condenser vacuum | 冷凝器真空 |
The sub-atmospheric pressure imposed on the condenser of a steam-power plant which leads to an appreciable increase in overall efficiency. 施加在蒸汽发电厂冷凝器上的低于大气压的压力导致整体效率显着提高。 |
| Flange rotation | 法兰转角 |
Angular distortion of a flange under the influence of bolt and reaction forces. Measured with respect to the center of the cross section of the flange. 法兰在螺栓和反作用力影响下的角度变形。相对于法兰横截面的中心测量。 |
| 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。 |
| Statistic | 统计 |
A summary value calculated from the observed values in a sample. 根据样本中的观察值计算得出的汇总值。 |
| 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。 |
| Inspection gauge | 检验规 |
Any of various gauges used in manufacturing and quality control to check dimensions, finish, etc. 任何用于制造和质量控制的各种量规，以检查尺寸、光洁度等。 |
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