| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| 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。 |
| Actual cubic feet per minute | 实际立方英尺每分钟 |
(acfm) An obsolete (i.e. non-SI) measure of volumetric flow rate; the volume of a gas flowing per minute at actual operating pressure and temperature, as opposed to the corresponding volume flow rate at STP. （acfm）已被淘汰的（即非SI）体积流量测量；在实际工作压力和温度下每分钟流动的气体体积，与STP下的相应体积流量相反。 |
| 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。 |
| Graphitizing | 石墨化退火 |
Annealing a ferrous alloy in such a way that some or all of the carbon is precipitated as graphite. 以使部分或全部碳以石墨的形式沉淀的方式对铁合金进行退火。 |
| Tracking problem | 跟踪问题 |
A control problem where the set point changes with time and thus the plant output must follow the changing set point. The opposite of a regulator problem. 一种控制问题，其中设定值随时间变化，因此设备输出必须遵循变化的设定值。与调节器问题相反。 |
| Non-ferrous metal | 有色金属 |
Strictly, all metals and alloys that do not contain iron, but usually taken to mean aluminium- and copper-based alloys. 严格来说，所有不含铁的金属和合金，但通常指铝基和铜基合金。 |
| 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。 |
| Hypereutectoid alloy | 过共析合金 |
In an alloy system exhibiting a eutectoid, any alloy whose composition has an excess of alloying element compared with the eutectoid composition, and whose equilibrium microstructure contains some eutectoid structure. 在呈现共晶的合金系统中，合金成分比共晶成分多的任何合金，其平衡微观结构包含一些共晶结构。 |
| Initial preload | 初始预载 |
The tension created in a single bolt as it is tightened. Will usually be modified by subsequent assembly operations or by in-service loads and conditions. 拧紧单个螺栓时产生的张力。通常会通过后续的装配操作或在役负载和条件进行修改。 |
| Centre of pressure | 压力中心 |
1. The location, on an aerofoil or other body that develops lift, of the resultant lift force. 2. The location, on a surface submerged in a liquid, of the resultant force due to the pressure acting on the surface. Because hydrostatic pressure increases with depth, the centre of pressure is generally below the centroid of the surface. 1.在产生升力的机翼或其他物体上，合成升力的位置。2.在浸没在液体中的表面上，由于作用在表面上的压力而产生的合力的位置。由于静水压力随深度增加，压力中心通常低于表面质心。 |
| Ferralium | 铁素体钢 |
Ferralium is a type of Super Duplex Stainless Steel which is optimised for use within fasteners. 一种超级双相不锈钢，经过优化用于紧固件。 |
| Metre (m) | 米（m） |
The base unit of length in the SI system. It is equal to the distance travelled by light in vacuum in 1/299 792 458 seconds. SI系统中长度的基本单位。它等于光在真空中在1/299792458秒内传播的距离。 |
| Joint | 关节接合处 |
The part of a robot arm permitting either rotational or translational motion. Each joint provides a single degree of freedom, and thus a minimum of six is required if the robot is to be able to position and orientate the end effector anywhere within the workspace. A joint is described by four parameters: the joint angle, joint offset, joint twist, and link length. The joint angle is the angle between an extrapolation of the previous link length and the present link length, measured positive anticlockwise in a plane normal to the joint axis. This is variable in a rotational joint and fixed in a translational joint. The joint offset is the distance between the link length for the previous link and that for the present link, measured along the joint axis. This is variable for a translational joint and fixed for a rotational joint. The joint twist for the nth joint is the angle between the axes of joints Jn and Jn+1, measured positive anticlockwise in a plane normal to the link length and viewed from the position of the Jn+1 joint. The link length is the mutually perpendicular distance between planes passing through the axes of joint Jn and Jn+1. Both the joint twist and link length are fixed in all joints. 机器人手臂上允许旋转或平移运动的部分。每个接合处都有自由度，如果机器人要能够在工作空间内的任何位置定位和定向末端执行器，则至少需要六个接合处具有自由度。关节接合处由四个参数描述：关节角度、关节偏移、关节扭曲和链接长度。关节角度是在垂直于关节轴的平面内逆时针测量的先前连杆长度和当前连杆长度的外推之间的角度。这在旋转关节中是可变的，在平移关节中是固定的。关节偏移是沿关节轴测量的前一个连杆和当前连杆的连杆长度之间的距离。这对于平移关节是可变的，对于旋转关节是固定的。第n个关节的关节扭曲是关节Jn和Jn+1轴之间的角度，在垂直于连杆长度的平面内逆时针测量，从Jn+2关节的位置观察。连杆长度是穿过关节轴Jn和Jn+1的平面之间相互垂直的距离。关节扭曲和连杆长度在所有关节中都是固定的。 |
| Absorptance | 吸收率 |
(absorptivity, absorption coefficient, α) The fraction of radiant flux incident on a surface that is absorbed by the surface. The term also applies to absorption of radiation by a volume of fluid. For a semi-transparent surface, α + ρ + τ = 1, where ρ is the reflectance and τ is the transmittance. （吸收率，吸收系数，α）入射到表面的辐射通量被表面吸收的部分。该术语也适用于一定体积的流体对辐射的吸收。对于半透明表面，α+ρ+τ=1，其中ρ是反射率，τ是透射率。 |
| Cap nut | 盖型螺母 |
A nut with a blind threaded hole, for example a dome nut to cover the end of a bolt. 带有盲螺纹孔的螺母，例如用于覆盖螺栓末端的圆顶螺母。 |
| 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）。 |
| Fin | 翼 |
A thin projecting rib. 一根细长的凸肋。 |
| 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。 |
| Abradant | 研磨剂 |
The differently sized grits of hard materials such as emery employed for grinding, polishing, etc. The abrasive grade is determined by the grit size (grit number) originally related to the hole sizes in wire sieves. 用于研磨、抛光等的硬质材料（例如金刚砂）的不同尺寸粒度。磨料等级由最初与金属丝筛孔尺寸相关的粒度（粒度数）决定。 |
| Dynamic mechanical measurement | 动态机械测量 |
A technique in which either the modulus and/or damping of a substance under oscillatory load or displacement is measured as a function of temperature, frequency, or time, or a combination thereof. 一种技术，其中在振荡载荷或位移下测量物质的模量和/或阻尼作为温度、频率或时间或其组合的函数。 |
| Reverse pitch (Unit °) | 反向螺距（单位°） |
The pitch of a variable-pitch propeller that produces negative thrust. 产生负推力的变桨距螺旋桨的桨距。 |
| Centi (c) | 厘（c） |
An SI unit prefix indicating a multiplier of 0.01; thus centimetre is a unit of length equal to one one-hundredth of a metre or 10 mm. 表示乘数0.01的SI单位前缀；因此厘米是长度单位，等于一米的百分之一或10毫米。 |
| 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。 |
| Toughening mechanisms | 增韧机理 |
Various methods of increasing the resistance to crack initiation and propagation in materials. They include transformation toughening, in which the microstructure around the crack tip alters so as to slow down or arrest cracks; deflexion of cracks; various ways of de-sharpening crack tips; fibre bridging of cracks; and fibre pull-out. 增加材料中裂纹萌生和扩展阻力的各种方法。它们包括相变增韧，其中裂纹尖端周围的微观结构发生变化，以减缓或阻止裂纹；裂纹偏转；消除裂纹尖端锐化的各种方法；纤维桥接裂纹；和纤维拉出。 |
| 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。 |
| Cold die quenching | 冷模淬火 |
A quench utilizing cold, flat, or shaped dies to extract heat from a part. Cold die quenching is slow, expensive, and is limited to smaller parts with large surface areas. 利用冷、平或成型模具从零件中提取热量的淬火。冷模淬火速度慢、成本高，并且仅限于表面积较大的较小零件。 |
| Horsepower | 马力 |
Unit indicating the rate at which work is done. The electrical equivalent of one horsepower is 746 watts. 单位表示完成工作的速率。一马力的电当量为746瓦。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| ASME | ASME |
The American Society of Mechanical Engineers. 美国机械工程师学会。 |
| Liquation temperature | 液化温度 |
The lowest temperature at which partial melting can occur in an alloy that exhibits the greatest possible degree of segregation. 偏析程度最高的合金发生部分熔融的最低温度。 |
| Ductility | 延展性 |
The ability of a material to deform plastically before fracturing. Measured by elongation or reduction in area in a tensile test, by height of cupping in a cupping test, or by the radius or angle of bend in a bend test. 材料在断裂前发生塑性变形的能力。通过拉伸试验中的伸长率或面积减少量、杯突试验中的杯突高度或弯曲试验中的弯曲半径或角度来测量。 |
| Joule | 焦耳 |
The SI unit of energy. One joule is the work done by a force of one newton acting over a distance of one metre. The symbol is J, where 1 J = 1 N m. 国际单位制能量单位。一焦耳是一牛顿的力在一米的距离上所做的功。符号为J，其中1j=1m。 |
| Laser sintering | 激光烧结 |
A manufacturing technique by which parts are built layer by layer (each typically 20 μm thick) from plastic or metal (Direct Metal Laser Sintering, DMLS) material in powder form, each layer being sintered by a scanning laser. 一种制造技术，通过这种制造技术，零件由粉末形式的塑料或金属（直接金属激光烧结，DMLS）材料逐层（每个厚度通常为 20 微米）构建，每一层都由扫描激光烧结。 |
| Submerged-electrode furnace | 浸入式电极炉 |
A furnace used for liquid carburizing of parts by heating molten salt baths with the use of electrodes submerged in the ceramic lining. 一种通过使用浸入陶瓷衬里中的电极加热熔融盐浴对零件进行液体渗碳的炉。 |
| Thread rolling | 滚丝 |
Thread rolling (also known as roll threading) is a cold forming process for producing threads or other helical or annular forms by rolling the impression of hardened steel dies into the surface of a cylindrical or conical blank. Polygonal blanks are also thread rolled for the purpose of fabricating thread-forming and self-locking screws. The preferred polygonal shape is trilobular and is produced in flat die machines. 螺纹滚压（也称为滚压螺纹）是一种冷成型工艺，通过将硬化钢模具的压痕滚压到圆柱形或锥形坯料的表面来生产螺纹或其他螺旋或环形形状。多边形坯料也进行螺纹轧制，以制造螺纹成型和自锁螺钉。优选的多边形形状为三棱形，并在平模机中生产。 |
| 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。 |
| 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。 |
| 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。 |
| Air conditioning | 空调 |
The process of controlling the temperature and humidity in rooms, buildings, aircraft, passenger vehicles, etc. More generally it includes control of dust, levels of radiant heat, etc. 控制房间、建筑物、飞机、客运车辆等的温度和湿度的过程。更一般地说，它包括控制灰尘、辐射热水平等。 |
| Nominal power (Unit kW) | 公称功率（单位kW） |
1. For an internal combustion engine, the average power output of a typical production engine under normal working conditions measured according to SAE standard J 1349/ISO 1585. 2. For an electric motor, the rated equivalent mechanical power output. 1.对于内燃机，根据SAE标准J 1349/ISO 1585测量的正常工作条件下典型生产发动机的平均功率输出。2.对于电动机，额定等效机械功率输出。 |
| Thermal stresses | 热应力 |
Stresses in metal resulting from nonuniform temperature distribution. 由不均匀温度分布引起的金属应力。 |
| Microindentation hardness test | 显微压痕硬度测试 |
Hardness test using a calibrated machine to force a diamond indenter of specific geometry, under a test load of 1 to 1000 gramforce, into the surface of the test material and to measure the diagonal or diagonals of the indentation optically. 使用校准机器进行硬度试验，以在1至1000克力的试验载荷下，将特定几何形状的金刚石压头压入试验材料表面，并光学测量压痕的对角线。 |
| Stress wave | 应力波 |
An unbalanced force, such as an impact, applied at one location in a body sets the material there into vibration that is transmitted to adjacent elements and ultimately to all parts of the body in the form of stress waves or wave packets. 施加在物体某个位置的不平衡力（如冲击力）会使物体中的材料产生振动，并以应力波或波包的形式传递到相邻元件，最终传递到物体的所有部位。 |
| 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。 |
| 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。 |
| Punch | 冲床 |
1. A hand tool with a sharp point, used to mark the position of a hole centre in a workpiece prior to drilling. 2. A flat-ended tool with sharp edges, used to shear out a hole in a plate that is supported underneath on a die having a slightly larger same-shaped orifice. 1.一种带有尖头的手动工具，用于在钻孔前标记工件中孔中心的位置。2.一种具有锐边的平头工具，用于剪切板上的孔，该板支撑在具有稍大相同形状孔口的模具下方。 |
| Plane-stress fracture toughness (Kc) | 平面应力断裂韧性（Kc） |
In linear-elastic fracture mechanics, the value of the crack-extension resistance at the instability condition determined from the tangency between the R-curve and the critical crack-extension force curve of the specimen. 在线弹性断裂力学中，由试样的R曲线和临界裂纹扩展力曲线之间的切线确定的不稳定条件下裂纹扩展阻力的值。 |
| Screw displacement | 螺杆位移 |
A rotation of a rigid body about an axis accompanied by a translation of the body along the same axis. 刚体绕轴旋转，同时刚体沿同一轴平移。 |
| Normal stress (Unit N) | 法向应力（单位：N） |
The stress component perpendicular to a plane on which forces act. Normal stress may be either tensile stress or compressive stress. A stress in a fluid (such as pressure) or a solid, that is perpendicular to the surface on which it acts. The surface may be a real external surface or an imaginary internal one. 垂直于受力平面的应力分量。法向应力可以是拉应力或压应力。流体（如压力）或固体中垂直于其作用表面的应力。该表面可以是真实的外表面或假想的内表面。 |
| Proof strength (Unit Pa) | 验证强度（单位Pa） |
(proof stress, Rp, Rp,) The yield strength (offset yield strength) at some fixed value of the permanent strain given by the intersection of a line offset from, but parallel to, the elastic loading line and the engineering stress-engineering strain curve. The offset is arbitrary but is usually 0.1, 0.2, or 0.5% permanent strain (the proof strain). Used for materials which do not exhibit a sharply defined yield point. The notation Rp0.2 or Rp0.2 is employed for the 0.2% proof stress. （验证应力，Rp）在永久应变的某个固定值下的屈服强度（偏移屈服强度），由偏离但平行于弹性加载线的线与工程应力-工程应变曲线的交点给出。偏移是任意的，但通常为0.1、0.2或0.5%的永久应变（验证应变）。用于没有明确定义屈服点的材料。对于0.2%的验证应力，采用符号Rp0.2。 |
| Vickers hardness test | 维氏硬度测试 |
An indentation hardness test employing a 136° diamond pyramid indenter (Vickers) and variable loads, enabling the use of one hardness scale for all ranges of hardness—from very soft lead to tungsten carbide. Also know as diamond pyramid hardness test. 采用136°金刚石棱锥压头（维氏硬度计）和可变载荷的压痕硬度测试，能够对从极软铅到碳化钨的所有硬度范围使用一个硬度标度。也称为钻石金字塔硬度测试。 |
| 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。 |
| Proof load | 验证载荷（单位 N） |
The maximum, safe, static, tensile load which can be placed on a fastener without yielding it. Sometimes given as a force (in lb or N) sometimes as a stress (in psi or MPa). The test load in quality control to which different components made of different materials must be subjected without failing in order to perform properly. 可施加在紧固件上而不使其屈服的最大安全静态拉伸载荷。有时以力（lb或N）表示，有时以应力（psi或MPa）表示。质量控制中的测试负荷，由不同材料制成的不同部件必须经受该负荷，才能正常运行。 |
| Balancing machine | 平衡机 |
A device that assesses the state of static and dynamic balance of a rotating part, and indicates the magnitude and location of weights to be added to give balance. 一种装置，用于评估旋转部件的静态和动态平衡状态，并指示为获得平衡而添加的砝码的大小和位置。 |
| Pitch-circle diameter (Unit m) | 节圆直径（单位：m） |
The diameter of the circle (the pitch circle) centred on a component’s axis, around which holes or bolts are equally spaced. 以部件轴为中心的圆（节圆）的直径，孔或螺栓围绕其等距分布。 |
| Thermoelectric material | 热电材料 |
A material in which any of the thermoelectric phenomena, such as the Peltier, Seebeck, and Thomson effects, are especially strong. 一种热电现象特别强烈的材料，如珀尔帖效应、塞贝克效应和汤姆森效应。 |
| Screw extractor | 螺钉拔 |
A device for removing broken-off screws from threaded holes. It resembles a drill with, for broken right-hand threads, a fast (long-pitch) left-hand thread that is driven into a hole drilled in the broken screw, thus untwisting it. 从螺纹孔中去除断裂螺钉的装置。它类似于一个钻头，对于断裂的右螺纹，一个快速（长螺距）的左螺纹被打入在断裂螺钉上钻的孔中，从而将其松开。 |
| Critical cooling rate | 临界冷却速度 |
The rate of continuous cooling required to prevent undesirable transformation. For steel, it is the minimum rate at which austenite must be continuously cooled to suppress transformations above the Ms temperature. 防止不期望的转变所需的连续冷却速率。对于钢，它是奥氏体必须持续冷却以抑制Ms温度以上的转变的最小速率。 |
| Waviness | 波纹度 |
Waviness is periodic deviations from geometric surface, often sinusoidal in form and often determined by low-level oscillations of the machine-tool-workpiece system during machining. Typically, wavelengths range from 1 to 10 mm (0.04 to 0.4 in.) and wave heights from a few to several hundred micrometers. 波纹度是与几何表面的周期性偏差，其形式通常是正弦的，通常由机床-工件系统在加工过程中的低水平振荡决定。通常，波长范围为1至10毫米（0.04至0.4英寸），波高范围为几微米至几百微米。 |
| Altitude chamber | 高空舱 |
(hypobaric chamber) A chamber in which conditions at different altitudes are simulated by a combination of appropriate pressures, temperatures and relative humidity. （低压舱）通过适当的压力、温度和相对湿度的组合来模拟不同高度条件的舱室。 |
| 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。 |
| Radiator | 散热器 |
A heat exchanger used to transfer thermal energy from one fluid to another for heating or cooling purposes. Despite the name, the principal mode of heat transfer is convection rather than radiation. In motor vehicles, water circulated through the engine block is cooled as it flows through the tubes of an air-cooled heat exchanger. In domestic radiators, hot water from a boiler is circulated through a heat exchanger with a large surface area which transfers heat to the surrounding air. 一种热交换器，用于将热能从一种流体传递到另一种流体，用于加热或冷却。尽管有这个名字，但热传递的主要方式是对流而不是辐射。在机动车辆中，通过发动机缸体循环的水在流经风冷热交换器的管道时被冷却。在家用散热器中，来自锅炉的热水通过具有大表面积的热交换器循环，该热交换器将热量传递给周围的空气。 |
| Heat treatment | 热处理 |
(heat treating) Alteration of the mechanical properties of materials, particularly metals, by different sequences of heating, holding at temperature, and cooling at different rates. Heating and cooling a solid metal or alloy in such a way as to obtain desired conditions or properties. Heating for the sole purpose of hot working is excluded from the meaning of this definition. （热处理）材料，特别是金属的机械性能的改变，通过不同的加热顺序、温度保持和不同速率的冷却。加热和冷却固体金属或合金，以获得所需的条件或性能。仅用于热加工的加热不属于本定义的含义。 |
| 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。 |
| Screw area (Unit m²) | 螺丝面积（单位m²） |
The area of a circle described by the tips of a propeller. 螺旋桨尖端所描述的圆的面积。 |
| Tension | 拉伸 |
The force or load that produces elongation. 1. The condition in a bar, belt, cable, spring, string, wire, etc. that is being pulled from either end. 2. (tensile force) (unit N) The force associated with tension as in (1). It is measured by a tension meter. 伸长力产生伸长的力或载荷。1.从两端拉出的杆、带、电缆、弹簧、线、线等的状态。2.（张力）（单位N）与张力相关的力。 |
| Remaining stress | 残留应力 |
The stress remaining at a given time during a stress-relaxation test. See also stress relaxation. 在应力松弛试验期间在给定时间内剩余的应力。参见压力松弛。 |
| Shoulder bolt | 轴肩螺栓 |
A bolt for which the unthreaded cylindrical section between the thread and the head is of larger diameter than the threaded section, precisely machined to length and diameter and hardened 一种螺栓，其螺纹和头部之间的无螺纹圆柱段的直径大于螺纹段的直径，精确加工至长度和直径并硬化 |
| 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。 |
| 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。 |
| Torque monitor | 扭矩监测器 |
A torque tool control system which monitors the amount of torque being developed by the tool during use, but does not control the tool or the torque produced. 一种扭矩工具控制系统，监控工具在使用过程中产生的扭矩量，但不控制工具或产生的扭矩。 |
| 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。 |
| 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。 |
| Strain hardening | 应变硬化 |
An increase in hardness and strengthcaused by plastic deformation at temperatures below the recrystallization range. Also known as work hardening. (workhardening) The increase in stress above the initial yield stress required to deform a metal to greater strains in the plastic range at temperatures below the recrystallization range (cold working). Unloading after some strain or work input gives a harder and stronger material. 在低于再结晶范围的温度下，塑性变形导致硬度和强度的增加。也称为加工硬化。（加工硬化）在低于再结晶范围（冷加工）的温度下，使金属在塑性范围内变形至更大应变所需的高于初始屈服应力的应力增加。在一定的应变或功输入后卸载，会得到更硬、更强的材料。 |
| Surface hardening | 表面硬化 |
A generic term covering several processes applicable to a suitable ferrous alloy that produces, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are carbonitriding, carburizing, induction hardening, flame hardening, nitriding, and nitrocarburizing. Use of the applicable specific process name is preferred. 一个通用术语，涵盖适用于仅通过淬火硬化产生比型芯更硬或更耐磨的表面层的合适铁合金的几种工艺。表面层的化学成分没有显著改变。常用的工艺有碳氮共渗、渗碳、感应淬火、火焰淬火、氮化和氮碳共渗。最好使用适用的特定工艺名称。 |
| 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。 |
| Lead angle | 导角 |
The angle of the helix of a screw thread or worm thread. It is the measure of the inclination of a screw thread from a plane perpendicular to the axis of the screw. 螺纹或蜗杆螺纹的螺旋角。它是螺纹从垂直于螺钉轴线的平面的倾斜度的量度。 |
| 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。 |
| Turbomachine | 涡轮机械 |
(rotodynamic machine) A machine in which there is a transfer of energy between a continuous stream of fluid and a component, called a rotor, rotating about a fixed axis. Fans and turbines (gas, hydraulic, steam, or wind) are turbomachines in which energy is transferred to the rotor, causing it to rotate. Pumps and compressors are turbomachines in which energy is transferred from the externally driven rotor to the fluid. （旋转动力机器）在连续的流体流和绕固定轴旋转的部件（称为转子）之间进行能量传递的机器。风扇和涡轮机（燃气、液压、蒸汽或风力）是涡轮机械，其中能量传递到转子，使其旋转。泵和压缩机是涡轮机械，其中能量从外部驱动的转子传递到流体。 |
| Computed path control | 计算路径控制 |
In CNC or robotics, the use of a control program to determine the required path for the tool or end effector. This required path forms the set points for the motor controllers moving the machine tool or robot. 在CNC或机器人技术中，使用控制程序来确定工具或末端执行器所需的路径。这条所需的路径形成了用于移动机床或机器人的电机控制器的设定点。 |
| Centigrade heat unit | 摄氏热量单位 |
(Celsius heat unit, CHU) An obsolete (i.e. non-SI) unit equal to the energy required to increase the temperature of one pound of pure, air-free water from 14.5°C to 15.5°C at a pressure of one standard atmosphere. （摄氏热量单位，CHU）一个已被淘汰的（即非国际单位制）单位，等于在一个标准大气压的压力下将一磅纯净的无空气水的温度从14.5°C提高到15.5°C所需的能量. |
| 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。 |
| Wind tunnel | 风洞 |
A duct in which a controlled flow of air is used for testing and research. Types include blow down, closed circuit, open return, and open section. Closed-circuit tunnels may be pressurized or evacuated. The working section is usually situated immediately downstream of the flow-conditioning elements, which may include a plenum chamber, honeycomb, screens, turbulence grids, and a contraction. Immediately downstream there is usually a diffuser. For basic research the usual requirement is for uniform steady flow in the working section with low swirl and turbulence intensity. For some applications the flow may be density stratified, sheared, unsteady, or of high turbulence intensity. 用于测试和研究的可控气流管道。类型包括排污、闭路、开路回路和开路段。闭路隧道可加压或排空。工作段通常位于流量调节元件的下游，可包括增压室、蜂窝、滤网、湍流格栅和收缩管。紧靠下游通常有一个扩散器。对于基础研究，通常的要求是在低涡流和湍流强度的工作段中实现均匀稳定流动。对于某些应用，流动可能是密度分层、剪切、不稳定或高湍流强度。 |
| 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。 |
| Magnetic test | 磁性测试 |
Method used to test heat extraction rates of various quenchants. The test works by utilizing the change in magnetic properties of metals at their Curie point–the temperature above which metals lose their magnetism. 用于测试各种淬火剂的热提取率的方法。该测试通过利用金属在居里点（即金属失去磁性的温度）的磁性变化来进行。 |
| Torricellean barometer | 托里塞莱气压计 |
A vertical glass tube with its upper end sealed and the lower end submerged in a pool of mercury. The space above the mercury is under vacuum. The height to which the mercury rises up the tube is a measure of the barometric pressure. 一种垂直的玻璃管，上端密封，下端浸入汞池中。水银上方的空间处于真空状态。水银在管道中上升的高度是大气压力的量度。 |
| Relative humidity (ϕ) | 相对湿度（ψ） |
The ratio or percentage of the actual mass of moisture in a given volume of air at a given temperature to the maximum possible mass of moisture at the same temperature. 给定温度下给定体积空气中的实际水分质量与相同温度下的最大可能水分质量的比率或百分比。 |
| 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。 |
| 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。 |
| Standard deviation (σ) | 标准偏差（σ） |
A statistical term used to quantify the Scatter in a set of data points. If the standard deviation is small, most of the data points are ‘‘nearly equal.’’ A large deviation means less agreement. The most usual measure of the dispersion of observed values or results expressed as the positive square root of the variance. The square root of variance, a measure of the spread of data about the mean value. 用于量化一组数据点中分散度的统计术语。如果标准偏差很小，则大多数数据点“几乎相等”大的偏差意味着更少的一致性。观测值或结果离散度的最常用度量，表示为方差的正平方根。方差的平方根，衡量平均值的数据分布。 |
| Testing machine | 试验机 |
A machine used to apply either a steady or oscillatory or impact load to a testpiece. The load may be tensile, compressive, shear, bending, or torsional. 用于向试件施加稳定或振荡或冲击载荷的机器。载荷可以是拉伸的、压缩的、剪切的、弯曲的或扭转的。 |
| 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。 |
| 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。 |
| Computer vision | 计算机视觉 |
The digitization and processing of optical images/patterns by computer in order to recognize parts, orientation, etc. in manufacturing. 通过计算机对光学图像/图案进行数字化和处理，以在制造过程中识别零件、方向等。 |
| Superheating | 过热 |
Heating above the temperature at which an equilibrium phase transformation should occur without actually obtaining the transformation. 在不实际获得相变的情况下，加热到应发生平衡相变的温度以上。 |
| 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。 |
| Starting torque (Unit N.m) | 起动扭矩（单位：N.m） |
The torque developed by a motor at zero rotational speed in order to initiate rotation of the applied load. 电机在零转速下产生的扭矩，以启动所施加负载的旋转。 |
| Total-loss lubrication | 全损耗润滑 |
A system in which the lubricating oil for an internal-combustion engine is burned together with the fuel. 内燃机润滑油与燃料一起燃烧的系统。 |
| 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。 |
| 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。 |
| Deviation | 偏差 |
The difference between the actual value and the desired value of a controlled variable. 受控变量的实际值与期望值之间的差值。 |
| Specific heat capacity | 比热容 |
The heat necessary to raise the temperature of 1 kg of a substance by 1 K. It is measured in J/(kg K). 将1千克物质的温度升高1K所需的热量。单位为J/（kg K）。 |
| Thermoelectric converter | 热电转换器 |
(thermoelectric generator) A device consisting of series-connected alternate n- and p-type semiconductor elements sandwiched between two ceramic plates. Due to the Seebeck effect, electrical power is generated when a temperature difference is maintained across the plates. Due to the Peltier effect, a thermoelectric converter can act as either a thermoelectric heater or a thermoelectric cooler (thermoelectric refrigerator) by passing an electrical current through it. The thermoelectric figure of merit (Z), with unit 1/K, is a dimensional parameter on which the efficiency of a thermoelectric device is primarily dependent, defined by Z = σα2/k where α is the Seebeck coefficient, σ is the electrical conductivity, and k is the thermal conductivity. The product of Z and a temperature is non-dimensional. （热电发生器）由串联连接的交替的n型和p型半导体元件夹在两块陶瓷板之间组成的装置。由于塞贝克效应，当板之间保持温差时，就会产生电能。由于珀尔帖效应，热电转换器可以通过使电流通过而充当热电加热器或热电冷却器（热电制冷机）。热电优值（Z）和第一单元/K是一个尺寸参数，热电装置的效率主要取决于此，由Z=σα2/K定义，其中α是塞贝克系数，σ是电导率，K是热导率。Z和温度的乘积是无量纲的。 |
| Turn-of-nut method | 螺母转动法 |
It applies preload by turning a nut through an angle that corresponds to a given elongation. 它通过将螺母旋转一个与给定伸长率相对应的角度来施加预载荷。 |
| Barcol hardness test | 巴氏硬度测试 |
An indentation test, similar to the Shore hardness test but using a pointed indentor with a flat tip, used to determine the hardness of such materials as rigid plastics and composites. 一种压痕测试，类似于肖氏硬度测试，但使用带有扁平尖端的尖头压头，用于确定硬质塑料和复合材料等材料的硬度。 |
| Strength of bolt | 螺栓强度 |
An ambiguous term which can mean Ultimate strength or Proof load or Endurance limit or Yield strength. 一个模棱两可的术语，可表示极限强度或验证荷载或耐久极限或屈服强度。 |
| Final annealing | 最终退火 |
An imprecise term used to denote the last anneal given to a nonferrous alloy prior to shipment. 一个不精确的术语，用于表示有色金属合金在装运前的最后一次退火。 |
| Bend test | 弯曲试验 |
A test for determining the relative ductility of metal that is to be formed (usually sheet, strip, plate, or wire) or for determining soundness and toughness of metal (after welding, for example). The specimen is usually repeatedly bent over a specified diameter through a specified angle and then unbent for a specified number of cycles. There are four general types of bend tests, named according to the manner in which the forces are applied to the specimen to make the bend: free bend, guided bend, semiguided bend, and wrap-around bend. 确定待成形金属（通常为薄板、带材、板材或线材）的相对延展性或确定金属的坚固性和韧性（例如，焊接后）的试验。试样通常在规定的直径上重复弯曲一个规定的角度，然后在规定的循环次数内弯曲。弯曲试验有四种一般类型，根据施加在试样上的力进行弯曲的方式命名：自由弯曲、引导弯曲、半引导弯曲和环绕弯曲。 |
| Endurance | 耐力 |
The capacity of a material to withstand repeated application of stress. 材料承受反复施加应力的能力。 |
| Plane stress | 平面应力 |
The stress condition in linear-elastic fracture mechanics in which the stress in the thickness direction is zero; most nearly achieved in loading very thin sheet along a direction parallel to the surface of the sheet. Under plane-stress conditions, the plane of fracture instability is inclined 45° to the axis of the principal tensile stress. 线弹性断裂力学中厚度方向上的应力为零的应力条件；在沿着平行于薄片表面的方向加载非常薄的薄片时最接近。在平面应力条件下，断裂失稳平面与主拉应力轴倾斜45°。 |
| Surface hardness | 表面硬度 |
(superficial hardness) Indentation hardness on, and for some distance below, the surface of a component, as opposed to its bulk hardness. Depending on the resolution required, micro- or nano-hardness testing machines are employed. （表面硬度）与整体硬度相反，部件表面及其下方一定距离的压痕硬度。根据所需的分辨率，可使用微型或纳米硬度测试机。 |
| Activation energy | 活化能 |
(Ea, U) (Unit kJ/mol) The minimum energy for a chemical reaction to occur or for processes such as diffusion to take place in crystals. （Ea, U）（单位kJ/mol）发生化学反应或在晶体中发生扩散等过程的最小能量。 |
| Stress factor | 应力因子 |
A calibration constant used in ultrasonic measurement of bolt stress or strain. It is the ratio between the change in ultrasonic transit time caused by the change in length of the fastener, under load, to the total change in transit time. 用于螺栓应力或应变超声波测量的校准常数。它是由紧固件长度变化引起的超声波传输时间变化与总传输时间变化之间的比率。 |
| 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 |
| 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。 |
| Manometer | 压力计 |
An instrument used in the measurement of a pressure difference in a fluid (manometry). 用于测量流体压力差（测压）的仪器。 |
| Regenerative pump | 涡流泵 |
(regenerative turbine pump, peripheral pump) A pump with a double-sided impeller having a large number of radial blades. The pressure of the pumped liquid increases progressively over several revolutions of the impeller. It is particularly suited to producing large heads at small flow rates without cavitation. （再生涡轮泵，外围泵）具有具有大量径向叶片的双面叶轮的泵。泵送液体的压力在叶轮的几圈内逐渐增加。它特别适合于在小流速下产生大水头且不产生气穴。 |
| 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。 |
| 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。 |
| Fastener standard | 紧固件标准 |
A document which details the attributes of a finished fastener and includes such characteristics as geometry, material or chemistry, heat treatment, finish, testing lot size, and packaging. 详细说明紧固件属性的文件，包括几何形状、材料或化学、热处理、表面处理、测试批量和包装等特性。 |
| 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。 |
| 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。 |
| Transmission | 传输 |
The system that transmits power and torque from a power source; for example a shaft, belts and pulleys, or a gear train. In the case of a motor vehicle, it includes the gearbox, clutch, propeller shaft, differential and final drive shafts. 从动力源传输功率和扭矩的系统；例如轴、皮带和滑轮或齿轮系。对于机动车辆，包括变速箱、离合器、传动轴、差速器和终传动轴。 |
| Boiler and Pressure Vessel Code | 锅炉和压力容器规范 |
A large and complex document, maintained and published by the American Society of Mechanical Engineers. The code 一份庞大而复杂的文件，由美国机械工程师协会出版和维护。 |
| 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。 |
| 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。 |
| Tear strength (Unit N/m) | 撕裂强度（单位：N/m） |
The tensile force divided by the sheet thickness required to tear a pre-split sheet material at a specified rate. Particularly used for plastics, rubber, fabrics, and elastomers. Since the units are not those of stress but equivalent to J/m², the units of toughness, the term ‘strength’ is strictly incorrect. 按规定速率撕裂预裂片材所需的张力除以片材厚度。特别用于塑料、橡胶、织物和弹性体。由于单位不是应力单位，而是相当于J/m²，韧性单位，“强度”一词是完全错误的。 |
| Wallner lines | Wallner线 |
A distinct pattern of intersecting sets of parallel lines, usually producing a set of V-shaped lines, sometimes observed when viewing brittle fracture surfaces at high magnification in an electron microscope. Wallner lines are attributed to interaction between a shock wave and a brittle crack front propagating at high velocity. Sometimes Wallner lines are misinterpreted as fatigue striations. 一组相交的平行线的独特图案，通常产生一组V形线，有时在电子显微镜下高倍观察脆性断裂表面时观察到。Wallner线归因于高速传播的冲击波和脆性裂纹前沿之间的相互作用。有时Wallner线被误解为疲劳条纹。 |
| Head height | 头部高度 |
The head height shall be that overall distance measured parallel to the axis of the product from the top of the head to the bearing surface and shall include the thickness of the washer face. Raised grade and manufacturer’s identification are excluded from head height. 头部高度应为平行于产品轴线从封头顶部到支承面测量的总距离，并应包括垫圈表面的厚度。提升等级和制造商标识不包括在头部高度中。 |
| 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。 |
| Turbine pump (turbopump) | 涡轮泵 |
An axial or centrifugal pump driven by a turbine. Typically used to supply fuel to the combustion chamber of a rocket engine such as on the space shuttle. 由涡轮驱动的轴向或离心泵。通常用于向火箭发动机（如航天飞机）的燃烧室供应燃料。 |
| Tension, bolt | 螺栓张力 |
Tension (tensile stress) created in the bolt by assembly preloads and=or such things as thermal expansion, service loads, etc. 由组件预载和=或热膨胀、工作载荷等因素在螺栓中产生的张力（拉伸应力）。 |
| 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。 |
| Acid rain | 酸雨 |
Any form of precipitation, including rain, snow, sleet, fog, dew, and particulates, which contains higher than normal levels of sulfuric and nitric acids. These acids result from natural and man-made emissions of sulfur dioxide and oxides of nitrogen, respectively. Acid soot consists of unburned carbon particles, typically larger than 10 μm, in the atmosphere contaminated with sulfuric acid. The particles result from poor combustion of fossil fuels. 任何形式的降水，包括雨、雪、雨夹雪、雾、露水和颗粒物，其中含有高于正常水平的硫酸和硝酸。这些酸分别来自二氧化硫和氮氧化物的自然排放和人为排放。酸烟灰由未燃烧的碳颗粒组成，通常大于10微米，在被硫酸污染的大气中。这些颗粒是化石燃料燃烧不良造成的。 |
| Captive nut | 松脱螺母 |
A nut attached loosely or rigidly to a sheet member that is too thin to thread and which engages with a cap screw. 松脱地或刚性地连接到薄板构件上的螺母，该螺母太薄而无法拧入，并与带帽螺钉接合。 |
| Shim | 垫片 |
A thin piece of material, such as metal of accurately-known thickness, placed between two surfaces to ensure they are the correct distance apart. A thin piece of material placed between two surfaces to obtain a proper fit, adjustment, or alignment. The piece can also be analyzed to measure furnace carbon potential (that is, because while in the furnace it will quickly carburize to a level equal to the furnace carbon potential). 一块薄的材料，如厚度精确已知的金属，放置在两个表面之间，以确保它们之间的距离正确。放置在两个表面之间以获得适当配合、调整或对齐的一块薄材料。还可以对工件进行分析，以测量熔炉碳势（也就是说，在熔炉中，工件将快速渗碳至与熔炉碳势能相等的水平）。 |
| Assembly drawing | 装配图纸 |
An engineering drawing that shows how parts are assembled to produce a component or a complete machine. It may include sections to show internal features, dimensions that are critical for assembly, manufacturing information, and part numbers. 显示零件如何组装以生产组件或整机的工程图。它可能包括显示内部特征、对装配至关重要的尺寸、制造信息和零件编号的部分。 |
| Octane number | 辛烷值 |
(octane rating) A measure of the anti-knock properties of a fuel taken as the percentage by volume of iso-octane in the fuel. （辛烷值）以燃料中异辛烷的体积百分比表示的燃料抗爆性能的量度。 |
| 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。 |
| 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、 |
| Tensile stress (Unit Pa) | 拉应力（单位Pa） |
A stress that causes two parts of an elastic body, on either side of a typical stress plane, to pull apart. A stress that tends to stretch a component, or local region of a component, when under load. In simple tension it results from the applied axial load, but tensile stresses occur in bending, torsion and other forms of loading. 一种应力，使弹性体的两个部分在典型应力平面的任一侧分离。在负载下，倾向于拉伸部件或部件局部区域的应力。在简单拉伸中，它由施加的轴向载荷产生，但拉伸应力发生在弯曲、扭转和其他形式的载荷中。 |
| Pitch | 沥青节距 |
The nominal distance between two adjacent thread roots or crests. In screw threads, the distance from a point on one thread to a corresponding point on the next thread measured parallel to the axis. In the case of spur gears, indicates the size of the gear teeth and is correctly called diametral pitch. 两个相邻螺纹根部或顶部之间的标称距离。在螺纹中，从一根螺纹上的一点到下一根螺纹对应点的距离，平行于轴线测量。对于正齿轮，表示齿轮齿的尺寸，正确地称为径向节距。 |
| Stress-relaxation curve | 应力松弛曲线 |
A plot of the remaining, or relaxed, stress in a stress-relaxation test as a function of time. The relaxed stress equals the initial stress minus the remaining stress. Also known as a stress-time curve. 应力松弛试验中剩余应力或松弛应力随时间变化的曲线图。松弛应力等于初始应力减去剩余应力。也称为应力-时间曲线。 |
| Hooke’s law | 胡克定律 |
Within the limit of proportionality, the extension of a material is proportional to the applied force. Approximately, it is the relationship between stress and strain in an elastic material when it is stretched. The law states that the stress (force per unit area) is proportional to the strain (a change in dimensions). The law, which holds only approximately and over a limited range, was discovered in 1676 by Robert Hooke. 在比例极限内，材料的延伸与所施加的力成比例。近似地说，它是弹性材料拉伸时应力和应变之间的关系。该定律指出，应力（单位面积的力）与应变（尺寸变化）成比例。该定律仅适用于有限的范围，由罗伯特·胡克于1676年发现。 |
| 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。 |
| DIN | DIN |
Deutsches Institut für Normung, the German Institute for Standardization. Deutsches Institut für Normung，德国标准化研究所。 |
| 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。 |
| Effective discharge area (Unit m²) | 有效排放面积（单位m²） |
A nominal area for flow through a pressure relief valve used to determine the valve’s flow capacity given the pressure difference across it, the fluid density and correction factors to allow for compressibility, the back pressure and the coefficient of discharge. 流经泄压阀的标称面积，用于确定阀门的流量，给定压力差、流体密度和允许可压缩性的校正因子、背压和排放系数。 |
| 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。 |
| Roots blower | 罗茨鼓风机 |
(rotary-piston blower) A positive-displacement gas compressor with two meshing lobed rotors that rotate within a close-fitting casing. Commonly used as a supercharger. （旋转活塞鼓风机）一种容积式气体压缩机，具有两个啮合的凸角转子，在紧密配合的外壳内旋转。通常用作增压器。 |
| 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。 |
| Total heat (Unit kJ) | 总热量（单位kJ） |
An alternative term for enthalpy. It is inappropriate as it suggests that it includes kinetic energy in the same way as total enthalpy, but it does not. Also, heat and enthalpy are quite different quantities, as their definitions show. 焓的另一个术语。这是不恰当的，因为它表明，它包括动能的方式与总焓相同，但它实际上并不是的。此外，热和焓是完全不同的量，正如它们的定义所示。 |
| 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。 |
| 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。 |
| 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。 |
| Air-hardening steel | 空气硬化钢 |
A steel containing sufficient carbon and other alloying elements to harden fully during cooling in air or other gaseous mediums from a temperature above its transformation range. The terms should be restricted to steels that are capable of being hardened by cooling in air in fairly large sections, about 2 in. (50 mm) or more in diameter. Same as self-hardening steel. 一种钢，含有足够的碳和其他合金元素，可以在空气或其他气体介质中从高于其转变范围的温度冷却过程中完全硬化。这些术语应仅限于能够通过在相当大的截面（直径约2英寸（50毫米）或更大）中通过空气冷却而硬化的钢。与自硬钢相同。 |
| 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。 |
| 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。 |
| Crossed threads | 交叉螺纹 |
When the axis of a nut offered up to a bolt is not aligned with the axis of a bolt (or a screw to a threaded member), it may be possible for the threads to engage incorrectly and even for the nut or screw to advance a turn or more, but ultimately the misaligned threads become locked together. Forcing the nut in such circumstances may irretrievably damage the threads on both. 当提供给螺栓的螺母的轴线与螺栓（或螺纹构件的螺钉）的轴线不对齐时，螺纹可能会错误接合，甚至螺母或螺钉会提前一圈或更多，但最终未对齐的螺纹会锁定在一起。在这种情况下强行拧入螺母可能会对两侧的螺纹造成无法修复的损坏。 |
| 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。 |
| 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。 |
| Cooling curve | 冷却曲线 |
A curve showing the relation between time and temperature during the cooling of a material. 显示材料冷却过程中时间和温度之间关系的曲线。 |
| Air-cooled engine | 风冷发动机 |
An internal-combustion engine directly cooled by airflow, rather than by water flowing through the engine block being cooled by a radiator. 一种由气流直接冷却的内燃机，而不是通过流经发动机缸体的水被散热器冷却。 |
| Finished fastener | 精制紧固件 |
Fastener for which all manufacturing steps have been completed, with or without any surface coating and with full or reduced loadability, and which has not been machined into a test piece. 已完成所有制造步骤的紧固件，有或没有任何表面涂层，具有完全或降低的承载能力，并且尚未加工成试件。 |
| Transfer moulding | 转移模塑 |
(resin-transfer moulding, RTM) A method of compression moulding polymers in which the dies are closed before the operation starts. （树脂传递模塑，RTM）一种对聚合物进行压缩模塑的方法，其中模具在操作开始前关闭。 |
| 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）。 |
| Compression | 压缩 |
1. Loading, the principal effect of which is to squeeze and shorten a component or testpiece. 2. The reduction in volume and increase in density of a substance as a consequence of increased pressure. 1.加载，其主要作用是挤压和缩短部件或试件。2.压力增加导致物质体积减少和密度增加。 |
| 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。 |
| Blue annealing | 蓝色退火 |
Heating hot-rolled ferrous sheet in an open furnace to a temperature within the transformation range and then cooling in air, in order to soften the metal. The formation of a bluish oxide on the surface is incidental. 在开放式炉中将热轧铁板加热到转变范围内的温度，然后在空气中冷却，以软化金属。在表面上形成蓝色氧化物是偶然的。 |
| Conduit | 导管 |
A hollow object, of metal, plastic, glass, ceramic, etc., which is relatively long compared with its lateral dimensions and through which there is fluid flow. 由金属、塑料、玻璃、陶瓷等制成的中空物体，与其横向尺寸相比相对较长，并且有流体流过。 |
| Strain | 拉紧 |
The unit of change in the size or shape of a body due to force. Also known as nominal strain. 物体的大小或形状因力而变化的单位。也称为标称应变。 |
| 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。 |
| Compound pendulum | 复摆 |
A rigid body free to swing about an axis. 可绕轴自由摆动的刚体。 |
| Elastic recovery | 弹性恢复 |
Amount the dimension of a stressed elastic material returns to its original (unstressed) dimension on release of an applied load. In hardness testing, the shortening of the original dimensions of the indentation upon release of the applied load. 在释放施加的载荷时，受应力弹性材料的尺寸恢复到其原始（无应力）尺寸的量。在硬度测试中，当释放所施加的载荷时，压痕的原始尺寸缩短。 |
| Closed system | 封闭系统 |
A closed thermodynamic system consists of a fixed amount of mass. No mass can cross its boundary although energy can, in the form of work or heat, and its volume can change. 一个封闭的热力学系统由一定量的质量组成。能量可以以功或热的形式存在，其体积可以改变，但没有质量可以越过它的边界。 |
| Die screw | 模具螺丝 |
Tool used when threading cylindrical pieces beyond the capacity of a die plate. 对超出模板容量的圆柱件进行螺纹加工时使用的工具。 |
| Cylinder head | 气缸盖 |
The machined casting, typically of aluminium alloy or cast iron, that fits above the cylinder block of a piston engine and closes off the cylinders. It normally includes part of the combustion chambers and holes for the valves and spark plugs. 活塞式发动机缸体上方的机械铸件，通常由铝合金或铸铁制成，用于封闭气缸。它通常包括燃烧室的一部分以及阀门和火花塞的孔。 |
| Cemented carbides | 硬质合金 |
Sintered mixtures of refractory metal carbides (e.g. tungsten carbide) in a metal matrix binder such as cobalt, nickel, or iron. They have high melting point, toughness, compressive strength, and wear resistance. Applications include use in grinding wheels and papers, cutting tools, drill bits, wire-drawing dies, and ball-point pen tips. Sometimes known as hard metals when the application is to machine tools. 难熔金属碳化物（如碳化钨）在金属基体粘结剂（如钴、镍或铁）中的烧结混合物。它们具有高熔点、韧性、抗压强度和耐磨性。应用包括用于砂轮和纸张、切削工具、钻头、拉丝模和圆珠笔尖。当应用于机床时，有时称为硬金属。 |
| ABS polymer | ABS聚合物 |
A class of thermoplastic co-polymer consisting of the three monomers acrylonitrile, butadiene and styrene that has improved properties (particularly toughness) over the individual constituents. 一类由丙烯腈、丁二烯和苯乙烯三种单体组成的热塑性共聚物，其性能（特别是韧性）优于单个成分。 |
| Toothed belt | 齿带 |
A flat belt, typically of a reinforced-rubber material, with transverse teeth that engage with teeth on a wheel or pulley. 一种扁平皮带，通常由增强橡胶材料制成，带有横向齿，与车轮或皮带轮上的齿啮合。 |
| 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。 |
| 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。 |
| High-tensile bolt | 高强度螺栓 |
(high-tension bolt) A bolt manufactured from an alloy steel that has a high tensile strength of about 1 GPa. （高压螺栓）由合金钢制成的螺栓，具有约1GPa的高抗拉强度。 |
| Failure | 失效 |
The result when a body, component, or structure is incapable of performing the task for which it was designed. The term is often used without reference to what causes failure, such as fracture, buckling, excessive deformation, wear, or erosion. Failure criteria (failure theories, theories of strength) are mathematical expressions for the combinations of stress, strain, or strain energy at which materials fail, which are employed in design to dimension components. 主体、部件或结构无法执行其设计任务时的结果。该术语通常未提及导致失效的原因，如断裂、屈曲、过度变形、磨损或侵蚀。失效准则（失效理论、强度理论）是材料失效时应力、应变或应变能组合的数学表达式，用于部件尺寸设计。 |
| Vibration-testing machine (vibrator) | 振动试验机（振动器） |
Any machine that subjects components or systems to vibration at known amplitudes and frequencies in order to determine the response. vibratory equipment Vibrating process equipment, such as shakers, used to separate small and large particles, or feeders to supply particulate or granular material that may otherwise clog. 使部件或系统以已知振幅和频率振动以确定响应的任何机器。振动设备振动工艺设备，如用于分离小颗粒和大颗粒的振动筛，或用于供应可能堵塞的颗粒或粒状材料的给料机。 |
| 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 |
| 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。 |
| 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。 |
| 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。 |
| Decalescence | 退色 |
A phenomenon, associated with the transformation of alpha iron to gamma iron on the heating (superheating) of iron or steel, revealed by the darkening of the metal surface owing to the sudden decrease in temperature caused by the fast absorption of the latent heat of transformation. 一种现象，与铁或钢加热（过热）时α铁向γ铁的转变有关，由于转变潜热的快速吸收导致温度突然降低，金属表面变黑。 |
| 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。 |
| Conditioning heat treatment | 调质热处理 |
A preliminary heat treatment used to prepare a material for desired reaction to a subsequent heat treatment. For the term to be meaningful, the exact heat treatment must be specified. 用于制备材料的初步热处理，以便对随后的热处理进行所需的反应。为了使该术语有意义，必须指定确切的热处理。 |
| Thumb screw | 蝶形螺钉 |
A type of screw having a winged or knurled head for turning by hand when a quick and light clamping effect is desired. 一种螺钉，具有翼形或滚花头，当需要快速、轻夹紧效果时，可手动转动。 |
| 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。 |
| Dead centre | 止点 |
The point at which, in a crank mechanism, the piston connecting rod and crank are all in line so that there can be no driving moment. 在曲柄机构中，活塞连杆和曲柄都在一条线上，因此不会有驱动力矩。 |
| 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。 |
| Crank pin | 曲柄销 |
It is a short shaft parallel to the axis of the crankshaft but radially offset from it, to which is attached the big end of a connecting rod in a bearing. Sometimes the crank pin is supported at one end only (a wrist pin) but in built-up or one-piece forged crankshafts, the crank pin is supported by thick plates (crank arms, crank webs) at either end. 它是一个短轴，平行于曲轴的轴线，但径向偏移，轴承中连杆的大端连接到该短轴上。有时曲柄销仅在一端支撑（腕销），在组合式或整体锻造曲轴中，曲柄销在两端由厚板（曲柄臂、曲柄腹板）支撑。 |
| 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。 |
| Design stress (Unit Pa) | 设计应力（单位Pa） |
The greatest allowable stress in a component or structure that will not result in failure under normal operating conditions. 在正常操作条件下不会导致失效的部件或结构中的最大许用应力。 |
| 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。 |
| Unison ring | 协调环 |
In a turbomachine with adjustable guide or stator vanes, the ring to which a set of vanes is linked such that when the ring is rotated, all vane angles are adjusted. 在具有可调导向叶片或定子叶片的涡轮机中，一组叶片连接到的环，当环旋转时，所有叶片角度都可调整。 |
| Combustion efficiency | 燃烧效率 |
(source efficiency, ηCOMB) A performance measure for combustion equipment defined by ηCOMB = amount of heat released during combustion/(calorific value of the fuel burned). （源效率，ηCOMB）燃烧设备的性能度量，定义为ηCOMB=燃烧过程中释放的热量/（燃烧燃料的热值）。 |
| Tooth lock washers | 带齿锁紧垫圈 |
These washers serve to lock fasteners, such as bolts and nuts, to the component parts of an assembly, or increase the friction between the fasteners and the assembly. They are designated in a manner similar to helical spring lock washers, and are available in carbon steel. 这些垫圈用于将紧固件（如螺栓和螺母）锁定到组件的零部件上，或增加紧固件与组件之间的摩擦力。它们的设计方式类似于螺旋弹簧锁紧垫圈，可采用碳钢。 |
| Hardness profile | 硬度分布 |
Hardness as a function of distance from a fixed reference point (usually from the surface). 硬度作为距固定参考点（通常距表面）的距离的函数。 |
| Square thread | 方螺纹 |
A form of screw thread in which the cross–section of the thread forms a square, making the width of the thread equal to the space between the threads. 螺纹的一种形式，螺纹的横截面形成正方形，使螺纹的宽度等于螺纹之间的间距。 |
| Salt bath heat treatment | 盐浴热处理 |
Heat treatment carried out in a bath of molten salt. 在熔融盐浴中进行的热处理。 |
| 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。 |
| Thermodynamic state | 热力学状态 |
The condition of a system or working fluid according to its properties. 系统或工作流体根据其性质的状态。 |
| 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。 |
| Helical spring | 螺旋弹簧 |
A spring manufactured by forming elastic wire into a helix which may be cylindrical, conical, barrel-shaped, or hourglass in overall form. Closed-coiled springs are used in tension; open-coiled in both tension and compression. 一种弹簧，通过将弹性线材制成螺旋形而制成，螺旋形的整体形状可以是圆柱形、圆锥形、桶形或沙漏形。拉力采用闭合盘簧；在拉伸和压缩中都开卷。 |
| 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。 |
| Coarsening | 粗粒化 |
An increase in the grain size, usually, but not necessarily, by grain growth. 晶粒尺寸的增加，通常但不一定是晶粒变大。 |
| Absolute humidity | 绝对湿度 |
The weight of water vapor in a gadwater vapor mixture per unit volume of space occupied, expressed, for example, in grains or pounds per cubic foot. 单位体积空间占用的水蒸气混合物中水蒸气的重量，例如，以谷物或磅/立方英尺表示。 |
| 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。 |
| Tensiometer | 张力计 |
An instrument used to measure surface tension. 用来测量表面张力的仪器。 |
| Critical crack length (Unit m) | 临界裂纹长度（单位米） |
The crack length at which a given stress applied to a body will result in crack propagation and fracture. 施加到物体上的给定应力将导致裂纹扩展和断裂的裂纹长度。 |
| 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。 |
| Selective quenching | 局部淬火 |
Quenching only certain portions of an object. 仅淬火工件的某些部分。 |
| 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。 |
| Fracture toughness | 断裂韧性 |
A generic term for measures of resistance to extension of a crack. The term is sometimes restricted to results of fracture mechanics tests, which are directly applicable in fracture control. However, the term commonly includes results from simple tests of notched or precracked specimens not based on fracture mechanics analysis. Results from tests of the latter type are often useful for fracture control, based on either service experience or empirical correlations with fracture mechanics tests. 裂纹扩展阻力测量的通用术语。该术语有时仅限于断裂力学试验的结果，这些结果直接适用于断裂控制。该术语通常包括非基于断裂力学分析的切口或预裂纹试样的简单试验结果。基于使用经验或与断裂力学试验的经验相关性，后一类试验的结果通常有助于断裂控制。 |
| 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。 |
| Centrifugal compressor | 离心式压缩机 |
A compressor in which kinetic energy is added to a fluid by radial acceleration in an impeller and then converted into a pressure increase by flow though a diffuser. 一种压缩机，其中动能通过叶轮中的径向加速度添加到流体中，然后通过扩散器的流动转换为压力增加。 |
| 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°. |
| Oxidized surface (on steel) | 氧化表面（在钢上） |
Surface having a thin, tightly adhering, oxidized skin (from straw to blue in color), extending in from the edge of a coil or sheet. Sometimes called annealing border. 表面具有薄的、紧密粘附的氧化皮（从稻草色到蓝色），从线圈或薄片的边缘延伸。有时称为退火边界。 |
| Decompression chamber | 减压舱 |
A chamber in which ambient-air pressure can be increased to levels found in deep-sea diving. It is used to gradually acclimatize divers back to normal conditions and avoid ‘the bends’. 环境气压可以提高到深海潜水水平的腔室。它用于逐渐使潜水员适应正常条件，避免“弯曲”。 |
| 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。 |
| 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。 |
| 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。 |
| Induction heating | 感应加热 |
Heating by combined electrical resistance and hysteresis losses induced by subjecting a metal to the varying magnetic field surrounding a coil carrying alternating current. 通过将金属置于承载交流电的线圈周围的变化磁场中而引起的电阻和磁滞损耗的组合加热。 |
| 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。 |
| 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。 |
| Mohr–Coulomb yield criterion | Mohr–Coulomb屈服准则 |
A pressure-dependent yield criterion, according to which yielding occurs when the stress at a point in a material falls on the envelope created by the Mohr’s stress circles at yielding for various tests such as tension, shear, and compression that have different components of hydrostatic stress. 一种与压力相关的屈服准则，根据该准则，当材料中某一点的应力落在屈服时的莫尔应力圆所形成的包络线上时，即发生屈服，用于各种试验，如具有不同静水应力分量的拉伸、剪切和压缩。 |
| 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。 |
| Maximum allowable working pressure (Unit Pa) | 最大允许工作压力（单位Pa） |
The pressure on which the design of a pressure system is based and the highest pressure at which relief valves should be set. The lowest-rated component in the system typically has a design safety factor of 4. 压力系统设计所依据的压力和应设置安全阀的最高压力。系统中最低额定部件的设计安全系数通常为4。 |
| Zone melting (zone refining) | 区域熔炼（区域精炼） |
A process of purification of materials in which a narrow molten zone is moved along the length of the material, resulting in impurities being segregated at one end. 一种净化材料的过程，其中一个狭窄的熔融区沿材料长度移动，导致杂质在一端分离。 |
| Selective heating | 局部加热 |
Intentionally heating only certain portions of a workpiece. 有意仅加热工件的某些部分。 |
| Profile | 轮廓 |
The shape of a cross section of an object, such as an aerofoil or cam. 物体的横截面形状，如机翼或凸轮。 |
| Valve spring | 气门弹簧 |
The spring that restores a valve to its closed position after having been opened, and is also intended to prevent valve bounce. 在阀门打开后将其恢复到关闭位置的弹簧，也用于防止阀门反弹。 |
| Mean diameter (Unit m) | 平均直径（单位米） |
The average of the inside and outside diameters for a helical spring or hollow circular cylinder or sphere 螺旋弹簧或空心圆柱体或球体的内径和外径的平均值 |
| 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。 |
| Assembly line | 流水线 |
A system of mass production in which work is moved progressively from one operation to another, ultimately to give the final complete product. 一种大规模生产系统，其中工作逐渐从一个操作转移到另一个操作，最终得到完整产品。 |
| Torsion | 扭矩 |
A twisting deformation of a solid body about an axis in which lines that were initially parallel to the axis become helices. The twisting of an object about an axis due to an applied couple (torque). 一种固体绕轴的扭转变形，在该变形中，最初平行于轴的线变成螺旋线。由于施加的力偶（扭矩），物体绕轴扭曲。 |
| Span (Unit m) | 跨度（单位：m） |
A dimension measured between the extremities of a body or structure, such as between the tips of a wing or the supports of a bridge. 在身体或结构的末端之间测量的尺寸，如机翼尖端或桥梁支架之间。 |
| Active vibration suppression | 主动振动抑制 |
The reduction of undesirable vibration in components by feedback control. 通过反馈控制减少部件中的不良振动。 |
| 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。 |
| Combustion chamber | 炉膛 |
1. In a piston engine, the volume between the head of an individual cylinder and the crown of the piston in which the fuel–air mixture burns during each power stroke of the engine. 2. (combustor) In a gas-turbine engine, a ramjet, an afterburner, or a rocket motor, the component, often cylindrical or annular in shape, in which the fuel–air mixture burns in a continuous-flow process. 1.在活塞式发动机中，在发动机的每个动力冲程中，燃料-空气混合物燃烧的单个气缸盖和活塞顶之间的体积。2.（燃烧室）在燃气涡轮发动机、冲压发动机、加力燃烧室或火箭发动机中，燃料-空气混合物在连续流动过程中燃烧的部件，通常为圆柱形或环形。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Cone clutch | 锥形离合器 |
A friction clutch in which an internal cone moves axially in or out of engagement with an external cone. One or both surfaces is lined with high-friction material. 一种摩擦离合器，其中内锥与外锥轴向啮合或脱离啮合。一个或两个表面衬有高摩擦材料。 |
| Dead space | 死区 |
(dead volume) (Unit m³) That volume of a gas-filled thermometer in which the gas is not at the same temperature as that being measured. （死容）（单位m³）充气温度计的体积，其中气体的温度与被测温度不同。 |
| 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。 |
| 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。 |
| Condensing boiler | 冷凝锅炉 |
A relatively small industrial or domestic boiler that burns sulfur-free natural gas so that the products of combustion do not contain sulfuric acid and can be allowed to condense on heat-transfer surfaces without danger of corrosion. 一种相对较小的工业或家用锅炉，燃烧无硫天然气，因此燃烧产物不含硫酸，并且可以在传热表面上冷凝而没有腐蚀的危险。 |
| Energy losses (Unit kJ) | 能量损失（单位kJ） |
A commonly-used misnomer in view of the conservation-ofenergy principle, but used to mean energy converted into forms that are not used in a process, for example thermal energy from a heat engine dissipated to the surroundings, or produced by friction in a machine, or by surface drag. 从能量守恒原理来看，这是一个常用的术语错误，但可以用于表示转换为过程中未使用的形式的能量，例如，从热机散发到周围环境的热能，或由机器中的摩擦或表面阻力产生的热能。 |
| Thermal compressor | 热压缩机 |
1. (thermocompressor) A jet compressor used to boost the pressure of low-pressure waste or exhaust steam. 2. A device consisting of an absorber, a generator, a pump, and a throttling device, used instead of a mechanical vapour compressor in an absorption-cooling refrigeration system. 1.（热压缩机）用于提升低压废蒸汽或排气压力的喷射压缩机。2.一种由吸收器、发电机、泵和节流装置组成的装置，用于替代吸收冷却制冷系统中的机械蒸汽压缩机。 |
| Guided-bend test | 导向弯曲试验 |
A test in which the specimen is bent to a definite shape by means of a punch (mandrel) and a bottom block. 用冲头（心轴）和底块将试样弯曲成一定形状的试验。 |
| 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。 |
| Right hand thread | 右旋螺纹 |
A screw thread which advances into the mating part when turned clockwise or to the right. 顺时针或向右转动时进入配合部件的螺纹。 |
| Secant modulus | 割线模量 |
The slope of the secant drawn from the origin to any specified point on a stress-strain curve. Compare with chord modulus. 从原点到应力应变曲线上任何指定点的割线斜率。与弦模量进行比较。 |
| 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。 |
| Proportional limit | 比例极限 |
The greatest stress a material is capable of developing without a deviation from straight-line proportionality between stress and strain. 材料能够产生的最大应力不偏离应力和应变之间的直线比例。 |
| Profilometer | 轮廓仪 |
An instrument used to quantify the roughness of a surface. For a contact profilometer, a diamond stylus sweeps across the surface along a series of parallel lines. Noncontact profilometers use optical techniques to map the surface irregularities. 用于量化表面粗糙度的仪器。对于接触式轮廓仪，钻石触针沿一系列平行线扫过表面。非接触式轮廓仪使用光学技术绘制表面不规则。 |
| Natural aging | 自然时效 |
Spontaneous aging of a supersaturated solid solution at room temperature. 过饱和固溶体在室温下的自发时效。 |
| Galvanic protection | 电流保护 |
The coating on a fastener is said to provide galvanic protection if it is more anodic than the fastener and will, therefore, be destroyed instead of the fastener. Zinc plate (galvanizing) provides galvanic protection to steel fasteners, for example. 如果紧固件上的涂层比紧固件更具阳极性，则据说它可以提供电流保护，将会因此被破坏而不是紧固。例如，锌板（镀锌）为钢紧固件提供电流保护。 |
| Balance weight | 平衡器 |
A corrective mass used in the static or dynamic balancing of a rotating object. 用于旋转物体的静态或动态平衡的校正质量。 |
| Snap temper | 快速回火 |
A precautionary interim stress-relieving treatment applied to high-hardenability steels immediately after quenching to prevent cracking because of delay in tempering them at the prescribed higher temperature. 在淬火后立即对高淬透性钢进行预防性临时应力消除处理，以防止因在规定的更高温度下回火延迟而开裂。 |
| Vapour static pressure | 蒸汽静压 |
(Unit Pa or bar) A pressure analogous to hydrostatic pressure, where the fluid is a vapour such as steam. A term used in geothermal applications. （单位Pa或bar）类似于静水压力的压力，其中流体是蒸汽，如蒸汽。地热应用中使用的术语。 |
| 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。 |
| Bioenergy | 生物能源 |
1. Energy derived from materials such as purpose-grown energy crops, including sugar cane, maize, wheat, and rice, as well as wood, straw, and animal waste, including sewage, manure, and animal litter. 2. A term sometimes used to cover biomass and biofuels together. 1.来自特定种植的能源作物（包括甘蔗、玉米、小麦和大米）以及木材、稻草和动物粪便（包括污水、粪便和动物垃圾）等材料的能源。2.有时用于同时涵盖生物质和生物燃料的术语。 |
| 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。 |
| Scale effect | 规模效应 |
The change in behaviour with size of a material, component, or structure. For example, cube-square scaling where one element changes with volume and another with area, as in the range of a projectile or ship, droplet formation, and fracture mechanics. 性能随材料、部件或结构尺寸的变化。例如，立方体平方比例，其中一个元素随体积变化，另一个元素因面积变化，如在射弹或飞船的射程、液滴形成和断裂力学中。 |
| Spinner | 旋转器 |
A co-axial streamlined fairing enclosing the hub of a propeller and rotating with it. 一种同轴流线型整流罩，包围螺旋桨毂并随其旋转。 |
| Cleavage fracture | 解理断裂 |
A fracture, usually of a polycrystalline metal, in which most of the grains have failed by cleavage, resulting in bright reflecting facets. It is one type of crystalline fracture and is associated with low energy brittle fracture. Contrast with shear fracture. A fracture created by splitting (cleavage), as between layers in materials like slate or mica. In brittle metals, and brittle microconstituents in alloys, cleavage occurs along particular crystal planes. 一种通过分裂（劈裂）产生的裂缝断裂，通常是多晶金属的断裂，其中大部分晶粒因解理而失效，产生明亮的反射面。它是一种结晶性断裂，与低能脆性断裂有关。与剪切断裂相对。如板岩或云母等材料的层之间。在脆性金属和合金中的脆性微量成分中，沿特定晶面发生解理。 |
| Pressure storage tank | 压力贮存器 |
(pressure vessel) A closed container for storing gases or volatile liquids, such as liquefied gases, at pressures significantly above atmospheric pressure. Such tanks are commonly cylindrical with domed ends, spherical, spheroidal, torispherical or hemispherical. （压力容器）密闭容器：在大气压以上的压力下储存气体或挥发性液体，如液化气体的密闭容器。此类贮存器通常为圆柱形，具有半球形端部、球形、球面或半球形。 |
| Turn-of-nut | 转动螺母 |
Sometimes used to describe the general rotation of the nut (or bolt head) as the fastener is tightened. More often used to define a particular tightening procedure in which a fastener is first tightened with a preselected torque, and is then tightened further by giving the nut an additional, measured, turn such as ‘‘three flats’’ (180°). 有时用于描述紧固件拧紧时螺母（或螺栓头）的总体旋转。更常用于定义一种特定的紧固程序，在该程序中，首先以预选扭矩拧紧紧固件，然后通过使螺母额外转动，如“三平面”（180°）进一步拧紧。 |
| Barometer | 气压计 |
An instrument used to measure atmospheric pressure. An instrument for measuring atmospheric pressure. There are two main types – the mercury barometer, and the aneroid barometer. 用于测量大气压力的仪器。有两种主要类型——水银气压计和无液气压计。 |
| Finish annealing | 精制退火 |
A subcritical annealing treatment applied to cold-worked low- or medium-carbon steel. Finish annealing, which is a compromise treatment, lowers residual stresses, thereby minimizing the risk of distortion in machining while retaining most of the benefits to machinability contributed by cold working. Compare with final annealing. 适用于冷加工低碳钢或中碳钢的亚临界退火处理。与最终退火相比，精加工退火是一种折衷处理，可降低残余应力，从而最大限度地降低加工中的变形风险，同时保留冷加工对可加工性的大部分好处。 |
| Ferritic stainless steels | 铁素体不锈钢 |
Ferritic stainless steels have the ferrite (BCC) crystal structure and contain 10–28% chromium and typically 0.1–0.35% carbon (all in wt%). They are magnetic and can be hardened by cold working. They have good to moderate mechanical properties, good oxidation and corrosion resistance at elevated temperatures, and susceptibility to embrittlement at temperatures between 400 and 540°C. Used for turbine parts, hightemperature valves, automotive exhaust components, and nuclear reactor core components. 铁素体不锈钢具有铁素体（BCC）晶体结构，含有10-28%的铬，通常含有0.1-0.35%的碳（均为重量%）。它们具有磁性，可通过冷加工硬化。它们具有良好至中等的机械性能，在高温下具有良好的抗氧化性和耐腐蚀性，在400至540°C的温度下易脆化。用于涡轮零件、高温阀、汽车排气部件和核反应堆堆芯部件。 |
| Tare weight (Unit N) | 皮重（单位N） |
The weight of an empty container. 空容器的重量。 |
| Toothed gearing | 齿轮传动 |
In principle, friction between circular discs in tangential contact could be used to transmit rotation and power between shafts, but the power level would be very limited and the velocity ratio affected by slip. To make the drive positive, gear wheels are used instead in which teeth extend above and below the diameters (the pitch-circle diameters) of discs in ideal rolling contact. The diagram shows the nomenclature for spur gears, the simplest type of gearing between parallel shafts, which are cylindrical in shape with straight teeth parallel to the axis of rotation. 原则上，切向接触的圆盘之间的摩擦可用于在轴之间传递旋转和动力，但动力水平非常有限，速比受滑动的影响。为了使驱动积极，使用齿轮代替，齿轮中的齿延伸到理想滚动接触的圆盘直径（节圆直径）的上方和下方。该图显示了直齿轮的名称，这是平行轴之间最简单的齿轮传动类型，其形状为圆柱形，直齿平行于旋转轴。 |
| Joint space | 关节空间 |
The description of the position and orientation of a robot in terms of the rotational angles and translational positions of the joints. Kinematic analysis, normally using homogeneous transforms, allows conversion between this description and the end‐effector position and orientation in x,y,z space. 根据关节的旋转角度和平移位置描述机器人的位置和方向。通常使用齐次变换的运动学分析允许在该描述与x、y、z空间中的末端执行器位置和方向之间进行转换。 |
| Wind velocity (Unit m/s) | 风速（单位：m/s） |
1. In the Earth’s atmosphere, a vector quantity that quantifies both the magnitude of the wind speed and its direction at a given altitude and location, conveniently represented in the hodograph plane. For convenience, the unit kph is often used. It could in principle also include information about large- and small-scale unsteadiness. Spatial variation in wind velocity, either with altitude or in a horizontal plane, is termed wind shear. 2. The airspeed in the working section of a wind tunnel. 1.在地球大气层中，一种矢量量，用于量化给定高度和位置处的风速大小及其方向，方便地用速度计平面表示。为方便起见，通常使用单位kph。原则上，它还可以包括关于大尺度和小尺度不稳定性的信息。风速随高度或水平面的空间变化称为风切变。2.风洞工作段的空速。 |
| Brake fluid | 制动液 |
The hydraulic fluid used to transmit force to the pistons in disc brakes or the wheel cylinders in drum brakes. Requirements include a high boiling point and low hygroscopy. 用于将力传递到盘式制动器中的活塞或鼓式制动器中的轮缸的液压油。要求包括高沸点和低吸湿性。 |
| 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。 |
| Air composition | 空气成分 |
The sea-level composition (in per cent by volume) of air at a temperature of 15°C and a pressure of 1 atm is mainly 78.084% nitrogen, 20.947% oxygen and 0.934% argon. The remaining 0.035% consists of carbon dioxide, neon, helium, methane, krypton, hydrogen, oxides of nitrogen, xenon, ozone, iodine, carbon monoxide, and ammonia. Different sources give slightly different figures for the composition. Not included are water vapour (typically 0.4%) and pollutants such as sulfur dioxide. 在15°C的温度和1个大气压的压力下，空气的海平面成分（体积百分比）主要是78.084%的氮气、20.947%的氧气和0.934%的氩气。剩余的0.035%由二氧化碳、氖、氦、甲烷、氪、氢、氮的氧化物、氙、臭氧、碘、一氧化碳和氨组成。不同的来源给出的组成略有不同。不包括水蒸气（通常为0.4%）和二氧化硫等污染物。 |
| 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。 |
| Atmometer | 气压计 |
(atmidometer, evaporimeter) An instrument that measures the rate of evaporation of water from a surface into the atmosphere. （湿度计，蒸发计）测量水从表面蒸发到大气中的速率的仪器。 |
| Forging | 锻造处理 |
The process of forming raw steel into specified shapes. Some examples of forged products would be hex bolts, clevises, and barrier pins. 1. A method of component manufacture by hammering metal by hand or by machine (drop forge, press). 2. A part made by the process of forging. 将生钢制成特定形状的过程。锻造产品的一些例子是六角螺栓、U形夹和障碍销。 1. 一种通过手工或机器锤击金属（落锻、压力机）制造部件的方法。2.通过锻造工艺制成的零件。 |
| 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。 |
| 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。 |
| 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。 |
| Extra hard | 额外硬化 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about one-third of the way from full hard to extra spring temper. 有色合金和一些铁合金的回火，其特征是抗拉强度和硬度大约是从完全硬回火到额外弹簧回火的三分之一。 |
| Wear rate | 磨损率 |
The rate of material removal or dimensional change due to wear per unit of exposure parameter—for example, quantity of material removed(mass, volume, thickness) in unit distance of sliding or unit time. 由于单位暴露参数的磨损而导致的材料去除率或尺寸变化，例如，单位滑动距离或单位时间内去除的材料数量（质量、体积、厚度）。 |
| Nipple | 喷嘴 |
A device containing a non-return valve screwed into a lubrication point through which grease may be introduced, for example into a bearing. 一种包含止回阀的装置，该止回阀拧入润滑点，通过该润滑点可以将润滑脂引入，例如轴承中。 |
| 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。 |
| Tempered martensite embrittlement | 回火马氏体脆化 |
Embrittlement of ultrahigh-strength steels caused by tempering in the temperature range of 205 to 400 °C (400 to 750 °F); also called 350 °C or 500 °F embrittlement. Tempered martensite embrittlement is thought to result from the combined effects of cementite precipitation on prioraustenite grain boundaries or interlath boundaries and the segregation of impurities at prioraustenite grain boundaries. 超高强度钢在205至400°C（400至750°F）温度范围内回火引起的脆化；也称为350°C或500°F脆化。回火马氏体脆化被认为是由于渗碳体沉淀在原奥氏体晶界或层间晶界上以及杂质在原奥氏体晶粒边界处偏析的综合影响。 |
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