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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。
Stroke 一击 1. (stroke length) (Unit m) The linear distance between top dead centre and bottom dead centre of a piston in a reciprocating engine or mechanism. 2. The movement of a piston or plunger in a reciprocating machine to execute a particular function; for example, the exhaust stroke of an engine in which the exhaust gases are expelled from a cylinder.
1.(冲程长度)(单位:m)往复式发动机或机构中活塞上止点和下止点之间的线性距离。2.活塞或柱塞在往复式机器中执行特定功能的运动;例如发动机的排气冲程,其中排气从气缸中排出。
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。
Impact testing 冲击测试 Determination of the mechanical properties of materials under high-rate conditions. Often determined from the behaviour of a testpiece when struck by a pendulum or a weight falling from a known height, or when sandwiched between two Hopkinson bars.
在高速条件下测定材料的机械性能。通常根据测试件在被钟摆撞击或从已知高度坠落的重物或夹在两个霍普金森棒之间时的行为来确定。
Crosshead 十字头 1. A reciprocating member, sliding between guides, to which the piston rod is firmly attached on one side and to which the connecting rod is pinned on the other for the conversion of reciprocating into rotary motion. 2. The moveable beam in early designs of mechanical testing machines. 3. A screwhead having slots in a + shape that takes a mating screwdriver.
1.一种往复式构件,在导轨之间滑动,活塞杆一侧固定在其上,连杆另一侧固定在该构件上,用于将往复式运动转换为旋转运动。2.机械试验机早期设计中的活动梁。3.一种螺钉头,其具有采用配合螺丝刀的+形槽。
Effective yield strength 有效屈服强度 An assumed value of uniaxial yield strength that represents the influence of plastic yielding on fracture test parameters.
单轴屈服强度的假设值,代表塑性屈服对断裂试验参数的影响。
Grain 晶粒 1. An individual crystal in a polycrystalline solid. Most engineering materials such as metals and ceramics are used in polycrystalline form. 2. (gr) A non-SI unit of mass. The conversion to SI is 1 gr = 6.479 891 × 10−5 kg.
1.多晶固体中的单个晶体。大多数工程材料,如金属和陶瓷,都以多晶形式使用。2.(gr)非国际单位制的质量单位。转换为SI为1gr=6.479891×10-5kg。
Anelastic 无弹性 Literally ‘not elastic’, but in practice used for materials that display timedependent recovery on unloading.
字面意思是“没有弹性”,但实际上用于在卸载时显示随时间恢复的材料。
Torque meter 扭矩计 An instrument for measuring torque using spring-loaded, piezoelectric, or strain-gauged devices.
使用弹簧加载、压电或应变测量装置测量扭矩的仪器。
Meyer hardness (Unit Pa) 迈耶硬度(单位Pa) A material hardness similar to the Brinell hardness but based upon the projected area of the impression rather than the surface area.
与布氏硬度相似的材料硬度,但基于印模的投影面积而不是表面面积。
Gasket factors 垫片系数 Experimentally derived ‘‘constants’’ used to define the behavior of a gasket or the assembly and in-service conditions required for acceptable behavior.
实验得出的“常数”用于定义垫圈的行为或可接受行为所需的组件和使用条件。
Lap joint 搭接接头 A riveted, welded, or bonded connection between two plates made by overlapping one plate above the other. Lap joints having plates above and below a butt joint avoid the bending moment associated with a simple lap joint.
两块板之间的铆接、焊接或粘结连接,通过将一块板重叠在另一块板上而形成。对接接头上方和下方具有板的搭接接头避免了与简单搭接接头相关的弯矩。
Slip band 滑带 A group of parallel slip lines so closely spaced as to appear as a single line when observed under an optical microscope.
一组平行滑移线,间距如此之近,以至于在光学显微镜下观察时显示为一条直线。
Sigma phase σ相 A hard, brittle, nonmagnetic intermediate phase with a tetragonal crystal structure, containing 30 atoms per unit cell, space group P42/mnm, occurring in many binary and ternary alloys of the transition elements. The composition of this phase in the various systems is not the same, and the phase usually exhibits a wide range in homogeneity. Alloying with a third transition element usually enlarges the field of homogeneity and extends it deep into the ternary section.
一种硬、脆、非磁性中间相,具有四方晶体结构,每单位晶胞含有30个原子,空间群P42/mnm,存在于许多过渡元素的二元和三元合金中。该相在各种系统中的组成不尽相同,并且该相通常表现出宽范围的均匀性。与第三过渡元素的合金化通常会扩大均匀性范围,并将其延伸到三元区。
Die 模具 1. A tool having an appropriately-shaped hole through which material may be extruded or drawn. 2. A tool employed in forging. 3. A block having the male or female shape employed in stamping operations. 4. A thick circular disc, driven by a die wrench, with internally-threaded cutting edges for producing a screw thread. A die wrench (die stock) holds a screw-cutting die and has two projecting arms for applying the torque necessary to cut the thread. A die having a hexagonal or square shape (die nut), driven by a spanner, is used in confined spaces where a die wrench cannot be rotated through a full circle.
1.一种具有适当形状的孔的工具,通过该孔可以挤压或拉伸材料。2.一种用于锻造的工具。3.一种用于冲压操作的具有阳或阴形状的块体。4.一种由模具扳手驱动的厚圆盘,具有用于产生螺纹的内螺纹切削刃。冲模扳手(冲模)装有一个螺旋切割模,并有两个突出臂,用于施加切割螺纹所需的扭矩。由扳手驱动的六边形或方形模具(模具螺母)用于模具扳手无法旋转一整圈的受限空间。
Abrasion 磨损 The removal of surface material by the scratching action of hard particles, either deliberately (abrasive papers, abrasive cleaning, abrasive machining) or as a consequence of operation (wear).
通过硬质颗粒的刮擦作用去除表面材料,可以是故意的(砂纸、研磨清洁、研磨加工),也可以是操作的结果(磨损)。
Ideal critical diameter 理想临界直径 (DI). Under an ideal quench condition, the bar diameter that has 50% martensite at the center of the bar when the surface is cooled at an infinitely rapid rate (that is, when H = ∞, where H is the quench severity factor).
(DI)在理想淬火条件下,当表面以无限快的速度冷却时(即H=∞, 其中H是淬火严重度因子)。
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。
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。
Slug wrench 缓动扳手 A box wrench with an anvil on the end of the handle. Torque is produced by striking the anvil with a sledge hammer.
柄端有铁砧的套筒扳手。扭矩是通过用大锤敲击铁砧产生的。
Stress distribution 应力分布 The manner in which tensile, compressive, and shear stresses are distributed within a loaded body, indicated by loci of constant stress.
拉应力、压应力和剪应力在受载物体内的分布方式,由恒定应力轨迹表示。
Torque multiplier 扭矩放大器 A gearbox used to multiply the torque produced by a small hand wrench (usually a Torque wrench). The output of the multiplier drives the nut or bolt with a torque that is higher, and a speed that is lower, than input torque and speed. There is no torque gage or readout on the multiplier.
一种齿轮箱,用于增加小手动扳手(通常是扭矩扳手)产生的扭矩。倍增器的输出以比输入扭矩和速度更高的扭矩和更低的速度驱动螺母或螺栓。倍增器上没有扭矩计或读数。
Autonomous energy system 自主能源系统 (stand-alone energy system) A sole source of electricity, usually small-scale, for applications remote from a grid, especially with energy storage in the system. Hydroelectric, photovoltaic, wind-power and other renewable systems are well suited to stand-alone applications.
(独立能源系统)一种唯一的电力来源,通常是小规模的,用于远离电网的应用,尤其是系统中的能量存储。水电、光伏、风力和其他可再生能源系统非常适合独立应用。
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。
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。
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。
Condenser 冷凝器 A heat exchanger in which a substance is changed from its vapour phase to its liquid phase by reducing its temperature to below the saturation temperature.
一种热交换器,通过将物质的温度降低到饱和温度以下,将其从气相变为液相。
Oil-cooled 油冷却 A term for a machine that uses circulating oil to remove heat.
使用循环油散热的机器的术语。
Weight (W) (Unit N) 重量(W)(单位:N) The force of attraction on a body due to gravity. A body’s weight is the product of its mass and the gravitational field strength at that point. Mass remains constant, but weight depends on the object’s position on the Earth’s surface, decreasing with increasing altitude. If g is the acceleration due to gravity, the weight of a mass m is given by W = mg. On Earth, the acceleration due to gravity is approximately 9.81 m/s², so that the weight of a 1 kg mass is 9.81 N. More generally, the weight is the force exerted on the mass of a body when in the gravitational field of another body.
重力由于重力作用在物体上的吸引力。物体的重量是其质量和该点引力场强度的乘积。质量保持不变,但重量取决于物体在地球表面的位置,随着海拔的升高而减小。如果g是重力引起的加速度,则质量m的重量由W=mg给出。在地球上,重力引起的加速度约为9.81m/s²,因此1千克质量的重量为9.81N。更一般地说,重量是在另一个物体的重力场中施加在物体质量上的力。
Bolt 螺栓 (machine bolt) A fastener in the form of an externally-threaded cylinder with a head on one end that is inserted through holes in assembled parts that are then held together by a nut tightened on to the thread. A bolt has an unthreaded region below the head so that when located in a hole, transverse loads are borne by two plain cylindrical surfaces in contact. In contrast, use of a machine screw, that has threads all along its length, results in threads bearing against the plain surface of a hole. Officially, a threaded fastener designed to be used with a nut.
(机械螺栓)外螺纹圆柱状紧固件:一端有头的紧固件,通过装配零件上的孔插入,然后通过拧紧到螺纹上的螺母固定在一起。螺栓头部下方有一个无螺纹区域,因此当位于孔中时,横向载荷由两个接触的平面圆柱面承担。相反,使用沿其长度具有螺纹的机器螺钉,会导致螺纹支撑在孔的平面上。正式情况下,螺纹紧固件设计用于与螺母一起使用。
A-basis A-基础 Mechanical property value above which at least 99% of the population of values is expected to fall, with a confidence of 95%. Also called A-allowable.
机械性能值超过该值时,至少99%的值预计会下降,置信度为95%。也被称为A-容许。
Dynamic hardness 动态硬度 (rebound hardness) The resistance of a material to local indentation by a rapidly-moving rigid indenter. In most practical methods the indenter is allowed to fall under gravity on to the surface of the material when the rebound height is a measure of the dynamic hardness.
(回弹硬度)材料对快速移动的刚性压头局部压痕的阻力。在大多数实际方法中,当回弹高度是动态硬度的测量值时,允许压头在重力作用下落在材料表面上。
Blowing 吹气 The process by which a gas is transferred through a porous surface over which there is a gas flow. The effect is used to decrease skin friction and increase heat transfer, for example in turbine-blade cooling.
气体通过有气流的多孔表面转移的过程。该效应用于减少表面摩擦和增加传热,例如在涡轮叶片冷却的过程中。
Cycle annealing 循环退火 An annealing process employing a predetermined and closely controlled time-temperature cycle to produce specific properties or microstructures.
采用预定且严格控制的时间-温度循环来产生特定性能或微观结构的退火工艺。
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)。
Eutectic melting 共晶熔化 Melting of localized microscopic areas whose composition corresponds to that of the eutectic in the system.
局部微观区域的熔化,其成分对应于系统中的共晶成分。
Angle of attack (α) 攻角(α) (Unit °) The angle between a reference line on a lifting body and the vector direction of the relative velocity between the body and the fluid through which it is moving. In the case of an aerofoil, turbine, or compressor blade, the usual reference line is the chord line.
(单位°)升力体上的参考线与升力体与其运动通过的流体之间的相对速度的矢量方向之间的角度。在机翼、涡轮或压缩机叶片的情况下,通常的参考线是弦线。
Least count 最小计数 The smallest value that can be read from an instrument having a graduated scale. Except on instruments provided with a vernier, the least count is that fraction of the smallest division which can be conveniently and reliably estimated; this fraction is ordinarily one-fifth or one-tenth, except where the graduations are very closely spaced.
可从具有刻度尺的仪器中读取的最小值。除配备游标的仪器外,最小计数是可以方便可靠地估计的最小除法的分数;这个分数通常是五分之一或十分之一,除非刻度间隔非常近。
ANSI ANSI The acronym for American National Standards Institute.
美国国家标准协会的缩写。
Rotational joint (revolute joint) 旋转关节 In robotics, a single degree-of-freedom joint where the controlled variable is the joint angle.
在机器人技术中,一种单自由度关节,其中受控变量为关节角度。
Notch depth 缺口深度 The distance from the surface of a notched test specimen to the bottom of the notch. In a cylindrical test specimen, the percentage of the original cross-sectional area removed by machining an annular groove.
从缺口试样表面到缺口底部的距离。在圆柱形试样中,通过加工环形槽去除的原始横截面积的百分比。
Free ferrite 游离铁氧体 Ferrite that is formed directly from the decomposition of hypoeutectoid austenite during cooling, without the simultaneous formation of cementite. Also proeutectoid ferrite.
在冷却过程中亚共析奥氏体分解直接形成的铁素体,没有同时形成渗碳体。也是先共析铁氧体。
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。
O-ring (O-ring seal) O形圈(O形密封圈) A toroidal ring of synthetic rubber seated in a groove machined into a flat or cylindrical surface to act as a seal.
一种环形合成橡胶环,位于加工成平面或圆柱表面的凹槽中,起密封作用。
Structural analysis 结构分析 The determination of the forces, displacements, stresses, and strains in a given structure.
确定给定结构中的力、位移、应力和应变。
Clevis joint U形接头 A joint formed by two parallel cantilever beams pressed upon a component between the beams.
由两个平行悬臂梁压在梁之间的部件上形成的接头。
Deformation (Unit 1/s) 变形(单位1/s) A change in the form of a body due to stress, thermal change, change in moisture, or other causes. In solid mechanics, any change, reversible (elastic) or permanent (plastic), in the shape or size of parts of a body, or the whole body, caused by external or internal loading. It includes extension, compression, bending, and twisting. The same state of deformation in a body can appear as different combinations of elongation and shear. To state how much of the total strain is shear, it is split into dilatation and deviatoric components, the former changing volume but not shape, the latter shape but not volume.
由于压力、热变化、水分变化或其他原因导致的身体形态变化。在固体力学中,由外部或内部载荷引起的身体各部分或整个身体的形状或大小的任何可逆(弹性)或永久(塑性)变化。它包括拉伸、压缩、弯曲和扭曲。物体中相同的变形状态可以表现为伸长和剪切的不同组合。为了说明总应变中有多少是剪切,将其分为膨胀分量和偏差分量,前者改变体积但不改变形状,后者改变形状但不改变体积。
Pin expansion test 插头膨胀试验 A test for determining the ability of a tube to be expanded or for revealing the presence of cracks or other longitudinal weaknesses in it, made by forcing a tapered pin into the open end of the tube, similar to flare test.
通过将锥形销压入管道开口端来确定管道膨胀能力或揭示其存在裂纹或其他纵向缺陷的试验,类似于扩口试验。
Oxygen probe 定氧测头 An atmosphere-monitoring device that electronically measures the difference between the partial pressure of oxygen in a furnace or furnace supply atmosphere and the external air.
一种大气监测装置,以电子方式测量熔炉或熔炉供应大气中的氧分压与外部空气之间的差值。
Lead of thread 螺纹导程 On a single threaded screw, the distance the screw or nut advances in one complete revolution.
在单螺纹螺钉上,螺钉或螺母在一整圈中前进的距离。
Austenite finish temperature (Af) 奥氏体完成温度(Af) Temperature at which the transformation of martensite into austenite completes upon heating. The same designation is also applied to nonferrous alloys in which martensite transforms into some parent phase.
加热时马氏体转变为奥氏体的温度。相同的名称也适用于马氏体转变为某些母相的有色合金。
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。
Cone pulley 锥轮 A stepped pulley having several diameters which, when linked by a laterallymoveable transmission belt to a corresponding pulley, gives a series of speed ratios.
具有多种直径的阶梯式皮带轮,当通过可横向移动的传动带连接到相应的皮带轮时,会产生一系列速比。
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。
Dead load (Unit N) 静载(单位N) A load on a component or structure that is steady with time, e.g. the self-weight of a bridge.
部件或结构上随时间稳定的载荷,例如桥梁的自重。
Ideal crack 理想裂缝 A simplified model of a crack used in elastic-stress analysis. In a stress-free body, the crack has two smooth surfaces that are coincident and join within the body along a smooth curve called the crack front; in two-dimensional representations, the crack front is called the crack tip.
用于弹性应力分析的裂纹简化模型。在无应力物体中,裂纹有两个光滑表面,它们在物体内沿称为裂纹前缘的平滑曲线重合并连接;在二维表示中,裂纹前缘称为裂纹尖端。
Oxidizing agent 氧化剂 A compound that causes oxidation, thereby itself becoming reduced.
一种引起氧化从而自身被还原的化合物。
Shrink fit 过盈配合 A tight interference fit between two components resulting from heating an outer part and/or cooling an inner part to allow easy assembly. The outer component contracts on cooling, while the inner part expands on warming to ambient temperature, thus gripping the two parts together.
由于加热外部部件和/或冷却内部部件而导致的两个部件之间的紧密过盈配合,以便于组装。外部部件在冷却时收缩,而内部部件在加热到环境温度时膨胀,从而将两个部件夹在一起。
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。
Elbow 肘部 1. A fitting that connects the ends of two pipes at an angle, 45°, 90°, and 180° being the most common. 2. The third joint on an articulated robot corresponding to the human elbow.
1.以45°、90°和180°角连接两个管道端部的配件。2.示例关节机器人上的第三关节对应于人的肘部。
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。
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。
Eccentric load 偏心载荷 The external load on a fastener or groups of fasteners is said to be eccentric if the resultant of that load does not pass through the centroid of the group of fasteners (eccentric shear load ) or does not coincide with the bolt axis (eccentric tensile load ).
如果一个或多个紧固件上的外部载荷的合力未穿过紧固件组的质心(偏心剪切载荷)或与螺栓轴不重合(偏心拉伸载荷),则称该外部载荷为偏心。
Atomic volume 原子体积 Volume of unit cell per atom.
每个原子的晶胞体积。
Intergranular cracking 沿晶断裂 Cracking or fracturing that occurs between the grains or crystals in a polycrystalline aggregate. Also called intercrystalline cracking.
多晶聚集体中的晶粒或晶体之间发生的开裂或断裂。也称为晶间断裂。
Stress area 应力面积 The effective cross-sectional area of the threaded section of a fastener. Used to compute average stress levels in that section. Based on the mean of pitch and minor diameters.
紧固件螺纹部分的有效横截面积。用于计算该截面中的平均应力水平。基于节距和小直径的平均值。
Absorber 吸收器 1. An auxiliary vibratory system that favourably modifies the vibration characteristics of a main system. 2. Part of an absorption refrigeration system in which the refrigerant is absorbed by a transport medium. 3. The absorber plate is the receiver of a concentrating solar collector where the radiation is absorbed.
1.一种辅助振动系统,可有利地改变主系统的振动特性。2.吸收式制冷系统的一部分,其中制冷剂被传输介质吸收。3.吸收板是吸收辐射的聚光太阳能集热器的接收器。
Computer numerical control (CNC) 计算机数控(CNC) A term relating to machine tools in which the movements of a tool and/or the workpiece are controlled by computer.
与机床相关的术语,其中工具和/或工件的运动由计算机控制。
Elongation measurement 伸张率测量 Bolt elongation is directly proportional to axial stress when the applied stress is within the elastic range of the material. If both ends of a bolt are accessible, a micrometer measurement of bolt length made before and after the application of tension will ensure the required axial stress is applied.
当施加的应力在材料的弹性范围内时,螺栓伸长率与轴向应力成正比。如果螺栓的两端都可以接近,则在施加张力前后对螺栓长度进行测微计测量,以确保施加所需的轴向应力。
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。
End-quench hardenability test 端淬淬透性试验 A laboratory procedure for determining the hardenability of a steel or other ferrous alloy. Hardenability is determined by heating a standard specimen above the upper critical temperature, placing the hot specimen in a fixture so that a stream of cold water impinges on one end, and, after cooling to room temperature is completed, measuring the hardness near the surface of the specimen at regularly spaced intervals along its length. The data are normally plotted as hardness versus distance from the quenched end.
测定钢或其他铁合金淬透性的实验室程序。淬透性是通过将标准试样加热到高于上临界温度,将热试样放置在夹具中,使冷水流冲击一端,并在冷却至室温后,沿试样长度以规则间隔测量试样表面附近的硬度来确定的。数据通常绘制为硬度与距淬火端距离的关系。
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。
Fine pitch 细牙螺纹 Fine pitch threads are often used within the automotive industry. They are more easily tapped into harder materials and have less tendency to loosen.
细螺距螺纹通常用于汽车行业。它们更容易被敲入较硬的材料中,并且不太容易松动。
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。
Steel-wire rope 钢丝绳 A rope or cable made up of many steel strands wrapped helically about an axis, each strand being made of metal wires twisted together like a helix.
一种绳索或缆绳,由许多绕轴螺旋缠绕的钢绞线组成,每根钢绞线由金属丝缠绕在一起形成螺旋。
Stress cycle 应力循环 The smallest segment of the stress-time function that is repeated periodically.
周期性重复的应力时间函数的最小段。
Sample standard deviation (s) 样本标准偏差(s) The square root of the sample variance. It is a point estimate of the population standard deviation, a measure of the “spread”of the frequency distribution of a population. This value of sprovides a statistic that is used in computing interval estimates and several test statistics. For small sample sizes, s underestimates the population standard deviation.
样本方差的平方根。它是总体标准偏差的点估计,是总体频率分布“扩散”的度量。SPR的这个值提供了一个用于计算区间估计和若干测试统计量的统计量。对于小样本,s低估了总体标准偏差。
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。
Thermal insulation (insulation) 隔热(绝缘) A material that may be a low-conductivity solid, or a porous solid or fabric in which there are voids containing air or another gas, resulting in overall low thermal conductivity. When applied to the surface of a hot or cold object, surface heat transfer is generally reduced.
一种材料,可以是低导电性固体,或多孔固体或织物,其中存在含有空气或其他气体的空隙,从而导致整体低导热性。当应用于热或冷物体的表面时,表面传热通常减少。
Torque converter 变矩器 A turbomachine used for torque amplification consisting of an impeller, a turbine, and a reaction member. Applications include motor-vehicle transmissions.
用于扭矩放大的涡轮机,由叶轮、涡轮机和反作用构件组成。应用包括机动车变速器。
Absorption hygrometer 吸收式湿度计 An instrument that determines the content of water vapour in the atmosphere by it being absorbed into a hygroscopic medium.
通过吸收到吸湿介质中来确定大气中水蒸气含量的仪器。
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。
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。
Ductile fracture 韧性断裂 Fracture characterized by tearing of metal accompanied by appreciable gross plastic deformation and expenditure of considerable energy. A fracture of a component or structure which is preceded by extensive ductile deformation so that the broken pieces cannot be re-fitted to regain the original size and shape of the component or structure.
以金属撕裂为特征的断裂,伴随着明显的总塑性变形和相当大的能量消耗。一种部件或结构的断裂,在断裂前会发生大范围的延性变形,从而使断裂的碎片无法重新装配以恢复部件或结构原来的尺寸和形状。
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。
Double aging 双级时效 Employment of two different aging treatments to control the type of precipitate formed from a supersaturated matrix in order to obtain the desired properties. The first aging treatment, sometimes referred to as intermediate or stabilizing, is usually carried out at higher temperature than the second.
采用两种不同的时效处理来控制由过饱和基质形成的沉淀物类型,以获得所需的性能。第一次时效处理,有时称为中间处理或稳定处理,通常在比第二次更高的温度下进行。
Critical temperature ranges 临界温度范围 Synonymous with transformation ranges, which is the preferred term.
与转换范围同义,这是首选术语。
Spring temper 弹簧回火 A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about two-thirds of the way from full hard to extra spring temper.
非铁合金和一些铁合金的一种回火,其特点是抗拉强度和硬度约为全硬回火到超弹性回火的三分之二。
Surface tension (σ, γ) (Unit N/m) 表面张力(σ,γ)(单位:N/m) At the interface between a liquid and a gas or two immiscible liquids, unbalanced cohesive forces acting on the liquid molecules at the interface lead to the property surface tension which causes tensile forces to develop as if it were a skin or membrane.
液体和气体或两种不混溶液体之间的界面处,作用在界面处的液体分子上的不平衡内聚力导致表面张力的性质,从而导致张力的发展,就像皮肤或薄膜一样。
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。
Torque (T) (Unit N.m) 扭矩(T)(单位:N.m) The twisting moment, product of force and wrench length, applied to a nut or bolt (for example). The twisting moment of a force or couple about an axis which results in torsion.
施加在螺母或螺栓(例如)上的扭矩,是力和扳手长度的乘积。力或力偶绕轴产生扭转的力矩。
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。
Verified loading range 验证加载范围 For testing machines, the range of indicated loads for which the testing machine gives results within the permissible variation specified.
对于试验机,试验机在规定允许偏差范围内给出结果的指示载荷范围。
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。
Minimum material condition 最小材料条件 (minimum metal condition) The situation where the volume of a manufactured component corresponds to the lower limit of all toleranced external dimensions and to the upper limit for all internal dimensions.
(最小金属条件)制造部件的体积对应于所有公差外部尺寸的下限和所有内部尺寸的上限的情况。
Relaxed stress 松弛应力 The initial stress minus the remaining stress at a given time during a stress-relaxation test.
在应力松弛试验期间,初始应力减去给定时间的剩余应力。
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。
Achme thread Achme螺纹 A screw thread having an included angle of 29° and largely used for feed screws on machine tools.
一种夹角为29°的螺纹,主要用于机床上的进给丝杠。
Materials selection 材料选择 The process of selecting the most suitable material for a particular application. In the case of solid materials, it involves assessment of candidate materials in terms of their physical properties (density, elastic moduli, fracture toughness, yield strength, hardness, fatigue resistance, coefficient of thermal expansion, thermal conductivity, resistance to thermal shock, creep resistance, corrosion resistance, radiation resistance, etc), and such factors as the function of the final product, its shape, method of manufacture, required tolerances, number to be made, ease of inspection and quality control, cost, and design methodology employed.
为特定应用选择最合适材料的过程。对于固体材料,它涉及根据其物理特性(密度、弹性模量、断裂韧性、屈服强度、硬度、抗疲劳性、热膨胀系数、导热系数、抗热冲击性、抗蠕变性、耐腐蚀性、抗辐射性等)评估候选材料,以及诸如最终产品的功能、其形状、制造方法、所需公差、制造数量、检查和质量控制的容易程度、成本和采用的设计方法等因素。
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。
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。
Celsius 摄氏度 The temperature scale based on the freezing point of water (0ºC) and the boiling point of water (100ºC). The interval between these points is divided into 100 degrees. The scale was devised by Anders Celsius.
基于水的冰点(0ºC)和水的沸点(100ºC)的温标。这些点之间的间隔被划分为100度。这个比例是由安德斯·摄氏设计的。
Creep 蠕变 The slow, plastic deformation of a body under heavy loads. Time-dependent plasticity. Time-dependent and permanent deformation of material under constant load or stress. The strain increases with time at a rate that increases with increasing temperature. Creep can lead to large strain and eventual failure, and so limit the lifetime of components subjected to load at high temperature. Creep in metals becomes significant at homologous temperatures in excess of about 0.4, e.g. 1200°C for tungsten, 504°C for titanium, 450°C for iron, and 100°C for aluminium.
物体在重载荷下缓慢的塑性变形,随时间变化的可塑性,材料在恒定载荷或应力下随时间变化的永久变形。应变随时间以随温度升高而增加的速率增加。蠕变可能导致大应变和最终失效,从而限制部件在高温下承受载荷的寿命。当同源温度超过约0.4℃时,金属蠕变变得显著,例如钨为1200℃,钛为504℃,铁为450℃,铝为100℃。
Hydraulic air compressor 液压空气压缩机 1. A compressor powered by a hydraulic motor. 2. A device in which air is compressed as a result of being entrained in water flowing in a downcomer pipe. The compressed air is released in a chamber at the bottom of the pipe.
1. 由液压马达驱动的压缩机。2.一种装置,其中空气由于夹带在降液管中流动的水中而被压缩。压缩空气在管道底部的腔室中释放。
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。
Fracture mechanics 断裂力学 The stress analysis of bodies containing cracks. The use of stressconcentration factors and other correction factors of traditional strength of materials is inadequate when flaws are present initially (or develop during loading), since fracture depends not only on stress but also the size of the crack. Traditional strength of materials stress calculations cannot predict either the safe working stress in the presence of a known flaw, or the critical size of flaw just tolerable with a given working stress.
含裂纹物体的应力分析。当初始存在缺陷(或在加载过程中形成缺陷)时,使用应力集中系数和传统材料强度的其他修正系数是不够的,因为断裂不仅取决于应力,还取决于裂纹的大小。传统的材料强度应力计算既不能预测已知缺陷存在时的安全工作应力,也不能预测给定工作应力下可容忍的缺陷临界尺寸。
Scratch hardness test 划痕硬度测试 A form of hardness test in which a sharp-pointed stylus or corner of a mineral specimen is traversed along a surface so as to determine the resistance of that surface to cutting or abrasion.
硬度测试的一种形式,用尖头笔或矿物样品的一角沿一个表面移动,以确定该表面的抗切割或耐磨性。
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。
Mean value 平均值 The average value of a number of data points. Computed by dividing the sum of all data by the number of data points.
多个数据点的平均值。通过将所有数据的总和除以数据点的数量来计算。
Process annealing 中间退火 An imprecise term denoting various treatments used to improve workability. For the term to be meaningful, the condition of the material and the time-temperature cycle used must be stated.
一个不精确的术语,表示用于改善可加工性的各种处理方法。为了使术语有意义,必须说明材料的条件和使用的时间-温度循环。
Creep rupture strength (Unit Pa) 蠕变断裂强度(单位Pa) The fracture stress at the end of a creep test in metals and polymers, often plotted against time to give a stress-rupture curve.
金属和聚合物蠕变试验结束时的断裂应力,通常与时间作图以给出应力-断裂曲线。
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。
Notch brittleness 缺口脆性 Susceptibility of a material to brittle fractureat points of stress concentration. For example, in a notch tensile test, the material is said to be notch brittle if the notch strengthis less than the tensile strength of an unnotched specimen. Otherwise, it is said to be notch ductile.
材料在应力集中点易发生脆性断裂。例如,在缺口拉伸试验中,如果缺口强度小于无缺口试样的抗拉强度,则称材料为缺口脆性材料。否则,称其为缺口韧性。
Microscopic stresses 微观应力 Residual stresses that vary from tension to compression in a distance (presumably approximating the grain size) that is small compared with the gage length in ordinary strain measurements. They are not detectable by dissection methods, but can sometimes be measured from line shift or line broadening in an x-ray diffraction pattern.
与普通应变测量中的标距相比,从拉伸到压缩的距离(大概接近晶粒尺寸)较小的残余应力。它们无法通过解剖方法检测到,但有时可以通过x射线衍射图案中的线位移或线加宽来测量。
Essential conditions 必要条件 Each type of failure to which bolted joints are subject is set up by three or four conditions. The conditions vary, depending on the mode of failure, but never number more than four. Eliminating any one of the essential conditions for a particular type of failure can prevent that type of failure.
螺栓连接所遭受的每种类型的故障都由三个或四个条件确定。根据故障模式的不同,情况会有所不同,但数量不得超过四个。消除特定类型故障的任何一个基本条件都可以防止该类型故障。
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。
Extra spring 额外弹簧 A temper of nonferrous alloys and some ferrous alloys corresponding approximately to a coldworked state above full hard beyond which further cold work will not measurably increase the strength and hardness.
有色金属合金和一些铁合金的回火状态,大约对应于高于全硬的冷加工状态,超过该状态进一步冷加工将不会显着增加强度和硬度。
Microstrain 微应变 The strain over a gage length comparable to interatomic distances. These are the strains being averaged by the macrostrain measurement. Microstrain is not measurable by currently existing techniques. Variance of the microstrain distribution can, however, be measured by x-ray diffraction.
与原子间距离相当的标距上的应变。这些是通过宏观应变测量得到的平均应变。现有技术无法测量微应变。然而微应变分布的变化可以通过x射线衍射来测量。
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。
Total combustion air (Unit kg/s) 总燃烧空气(单位:kg/s) 1. The combination of the stoichiometric flow of air required for combustion together with any excess air. 2. The flow of fresh air into a boiler plus any flue gas recirculated.
1.燃烧所需的化学计量空气流与任何过量空气的组合。2.进入锅炉的新鲜空气流加上再循环的任何烟气。
Acoustic emission 声发射 (stress-wave emission) Sound emitted by some materials when deformed under load. It arises from stress waves emitted by sudden dislocation motion in crystals, slip, crack growth, etc.
(应力波发射)某些材料在负载下变形时发出的声音。它是由晶体中突然的位错运动、滑移、裂纹扩展等发出的应力波引起的。
Strain aging 应变时效 The changes in ductility, hardness, yield point, and tensile strength that occur when a metal or alloy that has been cold worked is stored for some time. In steel, strain aging is characterized by a loss of ductility and a corresponding increase in hardness, yield point, and tensile strength.
已冷加工的金属或合金在储存一段时间后发生的延展性、硬度、屈服点和抗拉强度的变化。在钢中,应变时效的特点是延性损失,硬度、屈服点和抗拉强度相应增加。
U-bend U形管 U-bend A 180° bend in a pipe.
180°弯曲的管道。
Tera (T) 特拉(T) An SI unit prefix indicating a multiplier of 1012; thus terawatt (TW) is a unit of power equal to one trillion watts.
指示乘数1012的SI单位前缀;因此,太瓦(TW)是等于1万亿瓦的功率单位。
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。
Transition temperature (Unit K) 转变温度(单位K) (1) An arbitrarily defined temperature that lies within the temperature range in which metal fracture characteristics (as usually determined by tests of notched specimens) change rapidly, such as from primarily fibrous (shear)to primarily crystalline (cleavage) fracture. (2) Sometimes used to denote an arbitrarily defined temperature within a range in which the ductility changes rapidly with temperature. (transition point) 1. The temperature at which the mechanism of fracture in metal alloys having a face-centred cubic crystal structure changes from ductile void growth to brittle cleavage. 2. The temperature at which a material changes from one crystal state to another.
(1) 任意定义的温度,位于金属断裂特性(通常通过缺口试样的试验确定)快速变化的温度范围内,如从主要纤维(剪切)断裂到主要结晶(解理)断裂。(2) 有时用于表示延性随温度快速变化的范围内的任意定义的温度。(转变点)1.具有面心立方晶体结构的金属合金的断裂机制从韧性孔洞生长转变为脆性解理的温度。2.材料从一种晶体状态转变为另一种晶体的温度。
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。
Roughness 粗糙度 The deviations from the wavy surface itself, caused by geometry of the cutting tool and its wear, machining conditions, microstructure of the workpiece, vibrations in the system, and so on. Surface roughness changes as a surface goes through the wearing-in process, but may then stabilize.
由刀具的几何形状及其磨损、加工条件、工件的微观结构、系统中的振动等引起的与波状表面本身的偏差。表面粗糙度随着表面经过磨合过程而变化,但随后可能会稳定下来。
Fahrenheit 华氏度 The temperature scale based on the freezing point of water (32ºF) and the boiling point of water (212ºF). The interval between these points is divided into 180 equal parts. Although replaced by the Celsius scale, the Fahrenheit scale is still sometimes used for non-scientific measurements.
温标基于水的冰点(32ºF)和水的沸点(212ºF)。这些点之间的间隔被分成180等份。尽管被摄氏刻度所取代,华氏刻度有时仍用于非科学测量。
U-bolt U型螺栓 A rod threaded at both ends and bent into a U-shape. It is used for clamping. An externally threaded fastener bent in the shape of the letter U and with both ends threaded.
两端有螺纹并弯曲成U形的杆。用于夹紧。一种外螺纹紧固件,弯曲成字母U的形状,两端带有螺纹。
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。
Fatigue life (N) 疲劳寿命(N) The number of cycles of stress or strain of a specified character that a given specimen sustains before failure occurs.
给定试样在失效发生之前所承受的特定特征的应力或应变的循环次数。
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。
Fluid mechanics 流体力学 The study of fluids in motion (fluid dynamics) or fluid statics where there is no relative motion between fluid particles. Fluid statics concerns primarily the variation of pressure with altitude or depth; it includes aerostatics and hydrostatics. Fluid dynamics includes the topics of aerodynamics, gas dynamics, hydraulics, hydrodynamics and many aspects of acoustics, chemical engineering, flight, lubrication, meteorology, non-Newtonian fluid flow, oceanography, power-plant technology, propulsion, and turbomachinery.
研究运动中的流体(流体动力学)或流体静力学,其中流体粒子之间没有相对运动。流体静力学主要关注压力随高度或深度的变化;它包括空气静力学和流体静力学。流体动力学包括空气动力学、气体动力学、水力学、流体动力学以及声学、化学工程、飞行、润滑、气象学、非牛顿流体流动、海洋学、发电厂技术、推进和涡轮机械的许多方面。
Young’s modulus 杨氏模量 A term used synonymously with modulus of elasticity. The ratio of tensile or compressive stresses to the resulting strain.
与弹性模量同义的术语。拉伸或压缩应力与产生应变的比率。
Annealing carbon 退火碳 Fine, apparently amorphous carbon particles formed in white cast iron and certain steels during prolonged annealing. Also called temper carbon.
白口铸铁和某些钢在长时间退火过程中形成的细小、明显的无定形碳颗粒。也称为回火碳。
Gear pump 齿轮泵 A positive-displacement pump in which fluid is pumped by meshing gears, one driven and the other an idler gear, on parallel axes within a closed casing.
一种容积式泵,其中流体由啮合齿轮泵送,在封闭外壳内的平行轴上一个驱动,另一个为空套齿轮。
Universal joint (Hooke’s joint) 万向节(胡克接头) A double-pivoted connection that allows power and torque to be transmitted between two shafts at an angle to each other. For constant driving angular velocity of the input yoke, the angular velocity of the output yoke fluctuates by amounts depending on the angle of intersection of the shafts. Speeds of the driving and driven shafts may be made identical (giving a constant-velocity joint) when an intermediate shaft, at each end of which there is a universal joint, is interposed. The driving and driven shafts must be equally inclined to the intermediate shaft, the two forks of which must lie in the same plane.
一种双枢轴连接,允许动力和扭矩以一定角度在两个轴之间传递。对于输入磁轭的恒定驱动角速度,输出磁轭的角速度根据轴的相交角度波动。当插入中间轴时,驱动轴和从动轴的速度可以相同(提供恒定速度接头),中间轴的两端都有万向节。主动轴和从动轴必须与中间轴倾斜相等,中间轴的两个叉必须位于同一平面内。
Bearing area 承载面积 The product of the pin (or hole) diameter and specimen thickness in a bearing test. (bearing surface) (Unit m²) The projected area of a hole, such as a rivet hole, that carries a transverse load.
轴承测试中销(或孔)直径和试样厚度的乘积。(承载面)(单位m²)承载横向载荷的孔(例如铆钉孔)的投影面积。
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。
Coalescence 聚结 Growth of grains at the expense of the remainder by absorption or the growth of a phase or particle at the expense of the remainder by absorption or reprecipitation.
通过吸收以牺牲剩余为代价的晶粒的生长或以通过吸收或再沉淀为代价的以剩余为代价的相或颗粒的生长。
Ductile cast iron 球墨铸铁 A cast iron that has been treated while molten with an element such as magnesium or cerium to induce the formation of free graphite as nodules or spherulites, which imparts a measurable degree of ductility to the cast metal. Also known as nodular cast iron, spherulitic graphite cast iron and SG iron.
一种铸铁,在熔融时用镁或铈等元素进行处理,以诱导游离石墨形成为球粒或球晶,从而赋予铸造金属可测量的延展性。又称球墨铸铁、球晶石墨铸铁和SG铸铁。
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。
Nautical mile (M) 海里(M) A special unit of distance employed for marine and aerial navigation. The conversion to SI is 1 M = 1 852 m.
用于海上和空中导航的特殊距离单位。SI的转换为1M=1852m。
Thermocouple 热电偶 A device for measuring temperature, consisting of lengths of two dissimilar metals or alloys that are electrically joined at one end and connected to a voltage-measuring instrument at the other end. When one junction is hotter than the other, a thermal electromotive force is produced that is roughly proportional to the difference in temperature between the hot and cold junctions.
一种测量温度的装置,由两种不同的金属或合金组成,一端电连接,另一端与电压测量仪相连。当一个结比另一个结更热时,产生的热电动势大致与热结和冷结之间的温差成比例。
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。
Impact strength 1. (Unit Pa) 冲击强度1.(单位Pa) The stress to cause failure (by yielding or fracture) under conditions of high strain rate. 2. (Unit J) A term sometimes used to describe the energy required to fracture a specimen in a Charpy or Izod impact test even though the unit is not that of strength.
在高应变率条件下导致失效(通过屈服或断裂)的应力。2.(单位J)有时用于描述在夏比或悬臂梁式冲击试验中使样品断裂所需的能量,即使单位不是强度单位。
Stretch forming 拉伸成型 A manufacturing process in which sheet-metal components are physically stretched over a forming die using a press, punch, or edge clamps. Stretching combined with bending reduces springback.
一种制造工艺,其中使用压力机、冲头或边缘夹具在成形模上物理拉伸金属板部件。拉伸与弯曲相结合可减少回弹。
Torque pack 扭矩包 A geared wrench which multiplies input torque and provides a read-out of output torque. In effect, a combination of a Torque wrench and a Torque multiplier.
一种齿轮扳手,可增加输入扭矩并提供输出扭矩读数。实际上,它是扭矩扳手和扭矩倍增器的组合。
Shear strain 剪切应变 The tangent of the angular change, as a response to force, between two lines originally perpendicular to each other through a point in a body. Also known as shearing strain.
角变化的切线,作为对力的响应,在两条原本通过物体中的一个点相互垂直的线之间。也称为剪切应变。
Contact strength (Unit N) 接触强度(单位N) The maximum allowable load between contacting bodies converted into a stress.
换算成应力的接触体之间的最大允许载荷。
Stretch-bending test 拉伸弯曲试验 A simulative test for sheet metal formability in which a strip of sheet metal is clamped at its ends in lock beads and deformed in the center by a punch. Test conditions are chosen so that fracture occurs in the region of punch contact.
金属板成形性的模拟试验,其中金属板条在其端部夹紧在锁珠中,并通过冲头在中心变形。选择试验条件,以便在冲头接触区域发生断裂。
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。
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。
Critical load (Unit N) 临界负荷(单位N) 1. The applied load that causes propagation of an existing crack of known length, and hence fracture of a component or structure. 2. The applied load that results in buckling of a column of given end fixity.
1.导致已知长度的现有裂纹扩展并因此导致部件或结构断裂的施加荷载。2.导致具有给定端部固定性的柱屈曲的施加荷载。
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。
Tyre 轮胎 A flexible ring-shaped cover mounted on a wheel rim that supports the weight of a vehicle, such as a motor vehicle, aircraft, or bicycle, and transmits power and torque to a road surface. Some pneumatic tyres are inflated directly, others have a separate inner tube that is inflated. For certain applications, solid tyres are used.
车轮罩安装在轮辋上的柔性环形罩,用于支撑车辆(如机动车、飞机或自行车)的重量,并将动力和扭矩传递到路面。有些充气轮胎是直接充气的,有些轮胎有单独的内胎充气。对于某些应用,使用实心轮胎。
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。
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。
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。
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。
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。
Belt drive 带传动 Transmission of motion from one shaft to another by means of a continuous plain, or toothed, flexible band (belt) passing over pulleys. In contrast to chain drives, belt drives tend to be employed in low-torque applications. Reduction in transmissible power may occur due to stretch of a plain transmission belt which results in slack in the drive (belt creep) or slip of a belt on a driving or driven pulley (belt slip).
通过穿过滑轮的连续平带或带齿柔性带(带)将运动从一根轴传递到另一根轴。与链条传动相比,皮带传动往往用于低扭矩应用。由于普通传动带的拉伸可能会导致传动松弛(皮带蠕变)或主动或从动皮带轮上的皮带打滑(皮带打滑),从而导致传动功率降低。
Tow 拖拉 1. To cause a vehicle to move by pulling with a rope, chain, bar, etc. 2. A bundle of  fibres employed in reinforcement.
1.用绳子、链条、钢筋等拉动车辆移动。2.用于加固的纤维束。
Constant-force spring 恒力弹簧 A spring that has the same restoring force regardless of displacement. The most common type takes the form of a coiled strip that, owing to tight coiling during manufacture, is pre-stressed (a steel measuring tape is an example). The uncoiling force is approximately constant as the change of curvature of the strip is approximately constant. Not to be confused with a clockwork spring from which power can be obtained.
无论位移如何,具有相同恢复力的弹簧。最常见的类型是卷绕带,由于制造过程中的紧密卷绕,该卷绕带是预应力的(钢卷尺就是一个例子)。随着带材曲率的变化近似恒定,开卷力近似恒定。不要与可获得动力的发条弹簧混淆。
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。
Combined stresses 复合应力 The stress state at a point in a component subjected to combination of axial, bending, torsional loadings etc., acting along all reference axes.
沿所有参考轴作用的受轴向、弯曲、扭转载荷等组合作用的部件中某点的应力状态。
Centrifugal 离心式 Acting or moving in a direction away from the axis of rotation of a rotating body.
沿远离旋转体的旋转轴的方向作用或移动。
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。
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。
Angle of contact 接触角 (Unit °) The angle subtended at the centre of a pulley or sprocket wheel by the circumferential contact of a belt or chain.
(单位°)皮带或链条的圆周接触在皮带轮或链轮的中心所对的角度。
Monotron hardness test 摩诺硬度试验 An obsolete method of determining indentation hardnessby measuring the load required to force a spherical penetrator into a metal to a specified depth.
一种已被淘汰的方法,通过测量将球形侵彻体压入金属至规定深度所需的载荷来确定压痕硬度。
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。
Torque arm 扭力臂 A bar fixed at one end used to resist torque applied at the other, for example by an electric drill.
固定在一端的杆,用于抵抗施加在另一端的扭矩,如电钻。
Transverse direction 横向 Literally, the “across” direction, usually signifying a direction or plane perpendicular to the direction of working. In rolled plate or sheet, the direction across the width is often called long transverse, and the direction through the thickness, short transverse.
从字面上看,“横穿”方向,通常表示与工作方向垂直的方向或平面。在轧制钢板或薄板中,横跨宽度的方向通常称为长横向,穿过厚度的方向称为短横向。
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。
Newton (N) 牛顿(N) The basic unit of force in the SI system, defined as the force that results in an acceleration of 1 m/s² when acting on a 1 kg mass.
SI国际单位制中力的基本单位,定义为作用于1kg质量时产生1m/s²加速度的力。
Heat-treatable alloy 可热处理合金 An alloy that can be hardened by heat treatment.
一种可以通过热处理硬化的合金。
Drift pin 冲头 A round tapered steel pin used to align rivet holes so that the rivet will pass through the holes easily.
用于对齐铆钉孔的圆形锥形钢销,以便铆钉轻松穿过孔。
International Bureau of Weights and Measures 国际度量衡局IBWM (BIPM, Bureau International des Poids et Mesures) The intergovernmental organization which has the mandate to provide the basis for a single, coherent system of measurements, traceable to the International System of Units.
(BIPM,国际计量局)政府间组织,其任务是为可追溯到国际单位制的单一、一致的计量系统提供基础。
Nominal size 公称尺寸 The intended size of a component. The actual size will depend on manufacturing tolerances.
组件的预期尺寸。实际尺寸取决于制造公差。
Flange 法兰 Flange refers to a head style for bolts where there is a circular ‘flange’ under the head that acts like a washer to distribute a load. A flange is a projected flat rim or collar. 1. Annular rims at the ends of pipes (flanged pipe) or shafts by which they may be coupled together using bolts that pass through holes in the flanges (flange coupling, flange union), or by toggle clamps around the periphery. 2. An extended rim on a wheel that positions it laterally on a track. Commonly used for railway rolling stock. 3. The top and bottom parts of an I-beam.
法兰是指螺栓的头部样式,其中头部下方有一个圆形“法兰”,其作用类似于垫圈以分配载荷。凸缘是凸出的平轮辋或凸缘。1.管道(法兰管)或轴端部的环形边缘,通过这些边缘,可以使用穿过法兰孔的螺栓(法兰联轴器、法兰接头)或通过周边的肘节夹将管道连接在一起。2.车轮上的延伸轮辋,将其横向定位在轨道上。通常用于铁路车辆。3.工字梁的顶部和底部。
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。
Rpm (N) 转速(N) An abbreviation for revolutions per minute. It is a widely used non-SI unit for rotational speed. The corresponding angular velocity ω in rad/s is given by πN/30. Rps (revolutions per second) is also used, the angular velocity then being 2πN.
每分钟转数的缩写。它是一种广泛使用的转速非SI单位。相应的角速度ω,单位为rad/s,由πN/30给出。还使用Rps(每秒转数),此时角速度为2πN。
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。
Supercharging 增压 The process of increasing the mass flow rate of air (or air/fuel mixture) into the cylinder(s) of a piston engine using a compressor driven from the crankshaft (the supercharger). The power output is increased compared with a naturally-aspirated engine of the same capacity. The process also increases the air pressure and density to greater than ambient. In the past, most superchargers were mechanically driven from the engine’s crankshaft, but these have been largely superseded by turbochargers.
使用由曲轴(增压器)驱动的压缩机增加进入活塞式发动机气缸的空气(或空气/燃料混合物)质量流率的过程。与相同容量的自然吸气发动机相比,功率输出增加。该过程还将空气压力和密度增加到大于环境压力和密度。在过去,大多数增压器都是由发动机曲轴机械驱动的,但这些增压器在很大程度上已被涡轮增压器所取代。
Carbonization 碳化 Conversion of an organic substance into elemental carbon.
将有机物质转化为元素碳。
Check valve 止回阀 (clack valve, non-return valve) A mechanical device that allows fluid flow in one direction only. The numerous designs include ball, diaphragm, disc, lift, split disc, and swing check valves.
(瓣阀、止回阀)一种仅允许流体单向流动的机械装置。众多设计包括球阀、隔膜阀、盘阀、升降阀、分体盘阀和旋启式止回阀。
Hardness 硬度 A measure of the resistance of a material to surface indentation or abrasion; may be thought of as a function of the stress required to produce some specified type of surface deformation. There is no absolute scale for hardness; therefore, to express hardness quantitatively, each type of test has its own scale of arbitrarily defined hardness. Indentation hardness can be measured by Brinell hardness test, Rockwell hardness test, Vickers hardness test, Knoop hardness test, and the Scleroscope hardness test. The ability of a ductile material to resist permanent deformation. It is a measure of plastic flow properties determined principally by indentation testing, but scratch hardness and rebound hardness are also employed. hardness scales The different measures of hardness given by different tests, such as indentation pressure in the Brinell and in the Vickers hardness tests, and the different Rockwell hardness numbers.
测量材料对表面压痕或磨损的阻力;可以认为是产生某些特定类型的表面变形所需的应力的函数。硬度没有绝对刻度,因此为了定量表示硬度,每种类型的试验都有自己的任意定义硬度等级。压痕硬度可通过布氏硬度试验、洛氏硬度试验,维氏硬度试验和努氏硬度试验以及硬化镜硬度试验进行测量。延展性材料具有抵抗永久变形的能力,它是主要通过压痕测试确定的塑性流动性能的量度,也使用划痕硬度和回弹硬度。硬度标度不同试验给出的不同硬度测量值,如布氏硬度试验和维氏硬度试验中的压痕压力,以及不同的洛氏硬度值。
Centripetal 向心力 Acting or moving in a direction towards the axis of rotation.
在朝向旋转轴的方向上起作用或移动。
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。
Plowing In tribology, the formation of grooves by plastic deformation of the softer of two surfaces in relative motion.
在摩擦学中,通过相对运动的两个表面中较软的表面的塑性变形形成凹槽。
Crankshaft 曲轴 The main shaft, of which the cranks are a part, of a reciprocating single-or multi-cylinder machine. Crankshafts may be built up in sections or forged as a single component. In an engine, the reciprocating motion of the pistons transmits power to the crankshaft and causes it to rotate, whereas in a pump the crankshaft is driven and its rotation causes the pistons to reciprocate.
曲柄是往复式单缸或多缸机器主轴的一部分。曲轴可以分段组装或作为单个部件锻造。在发动机中,活塞的往复运动将动力传递给曲轴并使其旋转,而在泵中,曲轴被驱动,其旋转使活塞往复运动。
Austenitizing 奥氏体化 Forming austenite by heating a ferrous alloy into the transformation range (partial austenitizing) or above the transformation range (complete austenitizing). When used without qualification, the term implies complete austenitizing.
通过将铁合金加热到转变范围(部分奥氏体化)或高于转变范围(完全奥氏体化)来形成奥氏体。当不加限定地使用时,该术语意味着完全奥氏体化。
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。
Crest of screw thread 螺纹牙顶 The top surface joining the two sides of flanks of a thread.
连接螺纹牙侧两侧的顶面。
Gas compressor 气体压缩机 A machine which draws in a gas at low pressure and delivers it at high pressure, usually accompanied by a temperature increase. Compressor designs include axial, centrifugal, diaphragm, reciprocating, and rotary (including the blade compressor).
一种在低压下吸入气体并在高压下输送气体的机器,通常伴随着温度升高。压缩机设计包括轴流式、离心式、隔膜式、往复式和旋转式(包括叶片式压缩机)。
Embrittlement 脆化 The loss of ductility or fracture toughness of materials, either during processing or in service. The severe loss of ductility or toughness or both, of a material, usually a metal or alloy. Many forms of embrittlement can lead to brittle fracture. Many forms can occur during thermal treatment or elevated-temperature service (thermally induced embrittlement). Some of these forms of embrittlement, which affect steels, include blue brittleness, 885 °F (475 °C) embrittlement, quench-age embrittlement, sigma-phase embrittlement, strain-age embrittlement, temper embrittlement, tempered martensite embrittlement, and thermal embrittlement. In addition, steels and other metals and alloys can be embrittled by environmental conditions (environmentally assisted embrittlement). The forms of environmental embrittlement include acid embrittlement, caustic embrittlement, corrosion embrittlement, creep-rupture embrittlement, hydrogen embrittlement, liquid metal embrittlement, neutron embrittlement, solder embrittlement, solid metal embrittlement, and stress-corrosion cracking.
材料在加工或使用过程中的延展性或断裂韧性损失。通常是金属或合金的延展性或韧性或两者的严重损失。多种形式的脆化可导致脆性断裂。在热处理或高温服务期间,可能会出现多种形式(热致脆化)。影响钢的一些脆化形式包括蓝脆、885°F(475°C)脆化、淬火时效脆化、西格玛相脆化、应变时效脆化,回火脆化、回火马氏体脆化和热脆化。此外,钢和其他金属和合金可能因环境条件而脆化(环境辅助脆化)。环境脆化的形式包括酸脆化、碱脆化、腐蚀脆化、蠕变断裂脆化、氢脆化、液态金属脆化、中子脆化、焊料脆化、固态金属脆化和应力腐蚀开裂。
Malleable cast iron 可锻铸铁 A cast iron made by prolonged annealing of white cast iron in which decarburization or graphitization, or both, take place to eliminate some or all of the cementite. The graphite is in the form of temper carbon. If decarburization is the predominant reaction, the product will exhibit a light fracture surface, hence, “whiteheart malleable;” otherwise, the fracture surface will be dark, hence, “blackheart malleable.” Ferritic malleable has a predominantly ferritic matrix; pearlitic malleable may contain pearlitic, spheroidite or tempered martensite depending on heat treatment and desired hardness.
白口铸铁一种通过长时间退火制成的铸铁,脱碳,石墨化,或两者都发生,以消除部分或全部渗碳体。石墨是回火碳的形式。如果脱碳是主要反应,产品将呈现出较轻的断裂表面,“白心可锻”。否则,断裂表面将变暗,“黑心可锻”。铁素体可锻性材料主要为铁素体基体;根据热处理和所需硬度,珠光体可锻材料可能包含珠光体、球状体或回火马氏体。
Graphitic carbon 石墨碳 Free carbon in steel or cast iron.
钢或铸铁中的游离碳。
Clamping force 夹紧力 The equal and opposite forces which exist at the interface between two joint members. The clamping force is created by tightening the bolts, but is not always equal to the combined tension in the bolts. Hole interference problems, for example, can create a difference between clamping force and bolt loads.
存在于两个连接构件之间的界面处的相等和相反的力。夹紧力是通过拧紧螺栓产生的,但并不总是等于螺栓中的组合张力。例如,孔干涉问题可能会在夹紧力和螺栓载荷之间产生差异。
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。
Torr 托尔 A non-SI unit of pressure commonly used in vacuum systems; defined by 760 torr = 1 atm so that 1 torr = 133.322 368 4 Pa, and approximately equivalent to the pressure corresponding to 1 mm of mercury.
真空系统中常用的非SI压力单位;由760托=1大气压定义,因此1托=133.3223684帕,近似等于对应于1毫米汞柱的压力。
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。
Gear ratio 传动比 For two gears in contact, the ratio of the number of teeth on the driving gear to that on the driven gear.
对于接触的两个齿轮,主动齿轮上的齿数与从动齿轮上的齿数之比。
Refractory materials 耐火材料 Metals or ceramics that do not melt when exposed to temperature above about 1 500°C or deteriorate rapidly in a continuous temperature above about 550°C.
当暴露于高于约1500°C的温度时不熔化或在高于约550°C的连续温度下快速劣化的金属或陶瓷。
Cup washer 杯形垫圈 A dished leather or neoprene washer fitted to the rod end in some piston-style pumps.
在某些活塞式泵中,安装在杆端的碟形皮革或氯丁橡胶垫圈。
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。
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。
Critical compression ratio 临界压缩比 1. The compression ratio for incipient knock of hydrocarbon fuels as determined in a variable-compression single-cylinder piston engine. 2. The compression ratio at which an air–fuel mixture will spontaneously ignite due to the temperature increase produced.
1.在可变压缩单缸活塞发动机中确定的烃类燃料初期爆震的压缩比。2.空气-燃料混合物由于产生的温度升高而自燃的压缩比。
Radial-flow compressor 离心式压缩机 A compressor in which the working gas enters the machine axially and is compressed as it flows radially out through the impeller.
一种压缩机,其中工作气体轴向进入机器,并在通过叶轮径向流出时被压缩。
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。
Anode 阳极 That electrode in a battery or corrosion cell which produces electrons. It is the electrode which is destroyed (corrodes).
电池或腐蚀电池中产生电子的电极。被破坏(腐蚀)的是电极。
Compressed liquid 压缩液体 A liquid subjected to a pressure greater than the saturation pressure corresponding to its temperature.
承受大于与其温度对应的饱和压力的压力的液体。
Twist drill 麻花钻 A hardened-steel drill bit having one or more helical flutes running from a conical tip to the smooth part of the shank.
一种淬火钢钻头,具有一个或多个螺旋槽,从锥形尖端延伸到柄部的光滑部分。
Profiling machine 仿形机 (profile milling machine) A milling machine in which the cutter is guided by the contour of a pattern having the required shape.
(仿形铣床)铣刀由具有所需形状的图案轮廓引导的铣床。
Raised-face flange 凸面法兰 A flange which contacts its mating joint member only in the region in which the gasket is located. The flanges do not contact each other at the bolt circle.
仅在垫圈所在区域接触其配合接头构件的法兰。法兰在螺栓圆处不相互接触。
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。
Structural engineering 结构工程 A branch of civil engineering concerned with the design of buildings, dams, bridges, and other large structures.
土木工程的一个分支,涉及建筑物、水坝、桥梁和其他大型结构的设计。
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。
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。
Freezing point 冰点 The temperature at which a substance changes phase (or state) from liquid to solid. The freezing point for most substances increases as pressure increases. The reverse process, from solid to liquid, is melting; melting point is the same as freezing point.
物质从液态变为固态的温度。大多数物质的冰点随着压力的增加而增加。从固体到液体的逆过程是熔化;熔点与凝固点相同。
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。
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。
Lock nut 锁紧螺母 A type of nut that is prevented from loosening under vibration. The locking action is accomplished by squeezing, gripping or jamming against the bolt threads. A nut which provides extra resistance to vibration loosening (beyond that produced by proper Preload ), either by providing some form of Prevailing torque, or, in free-spinning lock nuts, by deforming, cramping, or biting into mating parts when fully tightened. 1. A thin auxiliary nut tightened against another nut to prevent loosening. 2. A single nut with special features that prevent loosening.
一种在振动下防止松动的螺母。锁定动作通过挤压、夹紧或卡住螺栓螺纹来完成。通过提供某种形式的主要扭矩,或在自由旋转锁紧螺母中,通过完全拧紧时变形、夹紧或咬入配合零件,提供额外的抗振动松动能力(超出适当预载产生的能力)。1.一个薄的辅助螺母,拧紧到另一个螺母上以防止松动。2.具有防止松动的特殊功能的单个螺母。
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。
Thermodynamic pressure (Unit Pa) 热力学压力(单位Pa) The pressure within a fluid given by an equation of state such as p(ρ,T) where ρ is the fluid density and T is the absolute temperature of the fluid.
流体中的压力由状态方程给出,如p(ρ,T),其中ρ是流体密度,T是流体的绝对温度。
Longitudinal direction 纵向 The principal direction of flow in a worked metal. See also normal direction and transverse direction.
加工金属中的主要流动方向。另请参见法向和横向。
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。
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。
Fatigue limit for p % survival p%存活率的疲劳极限 The limiting value of fatigue strength for p%survival as the number of stress cycles becomes very large; pmay be any number, such as 95, 90, etc.
随着应力循环次数的增加,p%存活率的疲劳强度极限值变得非常大;p可以是任何数字,例如95、90等。
Screw thread 螺纹 A ridge of uniform section or shape in the form of a helix on the external or internal surface of a cylinder, or in the form of a conical spiral on the external or internal surface of a cone.
在圆柱体的外表面或内表面上呈螺旋形或在圆锥体的外表面和内表面上以锥形螺旋形的均匀截面或形状的脊。
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。
Torsion bar 扭杆 A metal bar designed to act as an elastic spring when torque is applied.
当施加扭矩时用作弹性弹簧的金属棒。
Blank carburizing 毛坯渗碳 Simulating the carburizing operation without introducing carbon. This is usually accomplished by using an inert material in place of the carburizing agent, or by applying a suitable protective coating to the ferrous alloy.
在不引入碳的情况下模拟渗碳操作。这通常通过使用惰性材料代替渗碳剂或通过在铁合金上施加合适的保护涂层来实现。
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。
Artificial aging 人工时效 Aging above room temperature.
在室温以上的时效。
Uniform elongation 均匀伸长 The elongation at maximum load and immediately preceding the onset of necking in a tension test.
在拉伸试验中,在最大载荷下和颈缩开始之前的伸长率。
Martensitic stainless steels 马氏体不锈钢 Martensitic stainless steels are hardenable magnetic stainless steels that contain 9–18% chromium, 0.06–1.25% carbon, and typically up to about 2.5% in total of manganese, silicon, nickel, and molybdenum. They can be heat-treated such that martensite is the prime microconstituent, and are usually available in the annealed or quenched-and-tempered condition. They have excellent strength and high hardness, and good corrosion resistance. Uses include cutlery, surgical instruments, rifle barrels, steam turbine tubing and blading, jet engine components, hand tools, machine parts, fasteners, valves, springs, bearings, pump shafts, nozzles, mining equipment, and wear-resistant parts.
马氏体不锈钢是一种可硬化的磁性不锈钢,其铬含量为9-18%,碳含量为0.06-1.25%,锰、硅、镍和钼的总含量通常高达约2.5%。它们可以进行热处理,使马氏体成为主要的微组分,通常可在退火或淬火回火条件下获得。它们具有优异的强度和高硬度,以及良好的耐腐蚀性。用途包括餐具、外科器械、步枪枪管、蒸汽轮机管道和叶片、喷气发动机部件、手动工具、机械零件、紧固件、阀门、弹簧、轴承、泵轴、喷嘴、采矿设备和耐磨零件。
Ratchet coupling 棘轮联轴器 A joint employing a ratchet system between two shafts, so that not only does the driven shaft run in one direction only, but also the driven shaft can, if necessary, run more quickly than the driving shaft.
在两个轴之间采用棘轮系统的接头,这样不仅从动轴只能在一个方向上运行,而且在必要时,从动轴可以比驱动轴运行得更快。
Crest clearance (Unit m) 顶隙(单位米) For screw threads and gearing, the radial clearance between the crest of a thread (or gear) and the root of the engaging thread (or gear).
对于螺纹和齿轮,螺纹(或齿轮)的顶部与啮合螺纹(或齿轮)的根部之间的径向间隙。
Depth gauge 深度计 1. A precision instrument, typically consisting of a machine-divided steel rule passing through a hardened-steel cross head, used to measure the depths of slots, holes, shoulders, projections, etc. 2. A device used by divers to indicate the water depth.
1. 一种精密仪器,通常由穿过硬化钢十字头的机器分割钢尺组成,用于测量槽、孔、肩部、突起等的深度。 2. 潜水员用来指示深度的装置水深。
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。
Millimetre of mercury 毫米汞柱 A non-SI unit of pressure equal to the pressure exerted by a vertical column of mercury 1 mm high. Approximately equal to 133.3 Pa or 1 torr.
一种非SI压力单位,等于1毫米高的垂直水银柱施加的压力。大约等于133.3Pa或1托。
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。
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。
Equation, long form 方程,长格式 An equation which relates the torque applied to a bolt to the preload created in it, and involves fastener geometry and the coefficient of friction between mating surfaces. A theoretical equation based on rigid body mechanics and the assumption that the geometry of the fastener is perfectly described by blueprint dimensions.
将施加在螺栓上的扭矩与螺栓中产生的预载荷联系起来的方程,该方程涉及紧固件几何形状和配合面之间的摩擦系数。基于刚体力学和紧固件几何结构由蓝图尺寸完美描述的假设的理论方程。
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。
Slip joint 滑动接头 A mechanical connection which allows limited endwise relative movement of two components such as pipes, rods, and ducts.
一种机械连接,允许两个部件(如管道、杆和管道)进行有限的轴向相对运动。
Corrosion cell 腐蚀电池 A natural ‘‘battery’’ formed when two metals having different electrical potentials (an Anode and a Cathode) are connected together in the presence of a liquid (the Electrolyte).
当两种具有不同电势的金属(阳极和阴极)在液体(电解质)存在下连接在一起时形成的天然“电池”。
Compression stroke 压缩冲程 The stroke in a reciprocating compressor or engine during which the working fluid is compressed.
往复式压缩机或发动机中工作流体被压缩的冲程。
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。
Centrifugal clutch 离心离合器 A clutch that engages and disengages at a defined speed of rotation of the driving shaft, as when expanding friction shoes act against the inside of a drum.
一种离合器,以驱动轴规定的旋转速度接合和分离,如当膨胀的摩擦片作用在滚筒内部时。
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。
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。
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。
Flange bolt 法兰螺栓 A bolt with a built in washer-like flange just below the head.
在头部下方带有内置垫圈状法兰的螺栓。
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。
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。
Quench annealing 淬火退火 Annealing an austenitic ferrous alloy by solution heat treatment followed by rapid quenching.
通过固溶热处理然后快速淬火对奥氏体铁合金进行退火。
Rated power (Unit kW or hp) 额定功率(单位:千瓦或马力) (rated capacity, rated horsepower) The maximum power output that can be sustained continuously for any power-producing machine or system, such as an engine or a power plant.
(额定容量、额定马力)任何发电机器或系统(如发动机或发电厂)可连续维持的最大功率输出。
Permissible variation 允许偏差 For testing machines, the maximum allowable error in the value of the quantity indicated. It is convenient to express permissible variation in terms of the percent error.
对于试验机,所示数量值的最大允许误差。用误差百分比表示允许偏差是很方便的。
Fillister head 槽头 Similar to a pan head but with a smaller head diameter and a taller head, with higher vertical sides.
类似于盘头,但头部直径较小,头部较高,垂直边较高。
Available resource 可用资源 (total resource) (Unit J) The total annual energy theoretically available from a renewable-energy source, such as ocean waves, the wind, or the total incident solar energy.
(总资源)(单位J)理论上可从可再生能源(例如海浪、风或总入射太阳能)获得的年度总能量。
Sinter (sintering) 烧结 A solid-state diffusion densification process for the production of objects, particularly porous objects, from raw material in powder, granular, mesh, perforatedsheet, or fibre form by heating to a temperature below the melting point until the constituents bond together. It is used for ceramic materials and metals. Applications of sintered materials include filtration, separation, flow control, fluidization, and noise reduction. The bonding of adjacent surfaces in a mass of particles by molecular or atomic attraction on heating at high temperatures below the melting temperature of any constituent in the material. Sintering strengthens a powder mass and normally produces densification and, in powdered metals, recrystallization.
一种固态扩散致密化工艺,用于从粉末、粒状、网状、穿孔片或纤维形式的原材料中生产物体,尤其是多孔物体,方法是加热至低于熔点的温度,直到成分结合在一起。它用于陶瓷材料和金属。烧结材料的应用包括过滤、分离、流量控制、流化和降噪。在低于材料中任何成分熔化温度的高温下加热时,通过分子或原子引力将大量颗粒的相邻表面结合起来。烧结增强了粉末质量,通常会产生致密化,在粉末金属中还会产生再结晶。
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。
Sample median 样本中间值 The middle value when all observed values in a sample are arranged in order of magnitude. If an even number of samples are tested, the average of the two middlemost values is used. It is a point estimate of the population median, or 50% point.
当样本中的所有观测值按数量级排列时的中间值。如果测试的样本数为偶数,则使用两个中间值的平均值。这是人口中位数的一个点估计值,或50%的点。
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。
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。
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。
Kinetic friction 动摩擦 (dynamic friction, sliding friction) (Unit N) The sliding resistance to relative motion of two surfaces in contact with each other.
(动摩擦,滑动摩擦)(单位N)两个相互接触的表面相对运动的滑动阻力。
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。
Natural unit system (n.u. system) 自然单位制(n.u.制) A non-SI system of units, based on fundamental constants, used in high-energy and particle physics. The n.u. of speed is the speed of light in a vacuum, c0 = 299 792 458 m/s.
基于基本常数的非国际单位制,用于高能和粒子物理n.u.速度是真空中的光速,c0=299792458m/s。
Maximum allowable operating pressure (Unit Pa) 最大允许使用压力(单位Pa) The highest pressure at which any pressure system may be operated, usually 10 to 20% below the maximum allowable working pressure.
任何压力系统可运行的最高压力,通常比最大允许工作压力低10%至20%。
Imperial system 英制单位体系 The units of measurement developed in the UK. Formerly known as the fps system, which is an abbreviation for the ‘foot-pound-second system of units.
英国开发的计量单位。以前称为fps系统,是“英尺-磅-秒(foot-pound-second)单位制”的缩写。
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。
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。
Acceleration due to gravity 重力加速度 (acceleration of free fall, gravitational acceleration, g) (Unit m/s²) The acceleration of a freely-falling body in a vacuum, with a mean value at sea level of approximately 9.81 m/s².
(自由落体加速度,重力加速度,g)(单位m/s²)自由落体在真空中的加速度,在海平面处的平均值约为9.81m/s²。
Verification 检验 Checking or testing an instrument to ensure conformance with a specification.
检查或测试仪器以确保符合规范。
Air-cooled condenser 风冷冷凝器 A heat exchanger, in which the cooling medium is air, used to condense the exhaust steam from a steam turbine, the condensate being returned to the boiler.
一种热交换器,其中冷却介质为空气,用于冷凝蒸汽轮机排出的蒸汽,冷凝水返回锅炉。
Alternative energy 可替代能源 (alternate energy) Energy sources that are renewable and do not have the undesired consequences of fossil fuels and nuclear energy.
(替代能源)可再生能源,不会产生化石燃料和核能的不良后果。
Scleroscope hardness test 反跃式硬度试验 A dynamic indentation-hardness test using a calibrated instrument that drops a diamond-tipped hammer from a fixed height onto the surface of the material being tested. The height of rebound of the hammer is a measure of the hardness of the material. Also known as Shore hardness test.
使用校准仪器的动态压痕硬度测试,该仪器将金刚石锤从固定高度落在被测材料表面上。锤的回弹高度是材料硬度的一种度量。也称为肖氏硬度测试。
Length of engagement 啮合长度 It is the axial measurement within which the external and internal threads have theoretical contact.
它是外螺纹和内螺纹具有理论接触的轴向测量。
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。
Absolute expansion 绝对扩张 The true volumetric expansion of a liquid with temperature, after account is taken of any expansion of the container in which it is held.
考虑到容纳液体的容器的任何膨胀后,液体随温度的真实体积膨胀。
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。
Counter sink 台面水槽 To cut or shape a depression in an object so that the head of a screw may set flush or below the surface.
在物体上切割或塑造一个凹陷,使螺钉的头部可以齐平或低于表面。
Granular fracture 粒状断裂 A type of irregular surface produced when metal is broken that is characterized by a rough, grainlike appearance, rather than a smooth or fibrous one. It can be subclassified as transgranular or intergranular.
金属破碎时产生的一种不规则表面,其特征是粗糙的颗粒状外观,而不是光滑或纤维状的外观。它可以细分为穿晶或晶间。
Stress ratio (A or R) 应力比(A或R) The algebraic ratio of two specified stress values in a stress cycle. Two commonly used stress ratios are the ratio of the alternating stress amplitude to the mean stress, A = Sa/Sm, and the ratio of the minimum stress to the maximum stress, R = Smin/Smax.
应力循环中两个指定应力值的代数比。两种常用的应力比是交变应力振幅与平均应力之比,A=Sa/Sm,以及最小应力与最大应力之比R=Smin/Smax。
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。
Diffusion coefficient 扩散系数 A factor of proportionality representing the amount of substance diffusing across a unit area through a unit concentration gradient in unit time.
一个比例因子,表示在单位时间内通过单位浓度梯度扩散到单位面积上的物质量。
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。
Modulus of elasticity (E) 弹性模量(E) The measure of rigidity or stiffness of a metal; the ratio of stress, below the proportional limit, to the corresponding strain. In terms of the stress-strain diagram, the modulus of elasticity is the slope of the stress-strain curve in the range of linear proportionality of stress to strain.
金属的刚度或刚度的量度;低于比例极限的应力与相应应变之比。根据应力应变图,弹性模量是应力应变曲线在应力应变线性比例范围内的斜率。
Atmometer 气压计 (atmidometer, evaporimeter) An instrument that measures the rate of evaporation of water from a surface into the atmosphere.
(湿度计,蒸发计)测量水从表面蒸发到大气中的速率的仪器。
Yield point (Unit Pa) 屈服点(单位Pa) The first stress in a material, usually less than the maximum attainable stress, at which an increase in strain occurs without an increase in stress. Only certain metals—those which exhibit a localized, heterogeneous type of transition from elastic to plastic deformation—produce a yield point. If there is a decrease in stress after yielding, a distinction may be made between upper and lower yield points. The load at which a sudden drop in the flow curve occurs is called the upper yield point. The constant load shown on the flow curve is the lower yield point. (yield strength, yield stress, Rel, Rel) The stress at which the onset of permanent (plastic) deformation (yielding) occurs in a body under increasing loading. In some materials, a yield-point phenomenon occurs in which stress falls on initial yielding and plastic deformation continues without increase in stress as strain increases further. The yield criterion is the combination of normal and shear stresses which produces yielding under multiaxial loading.
材料中的第一应力,通常小于可达到的最大应力,在该应力下应变增加而应力不增加。只有某些金属——表现出从弹性变形到塑性变形的局部、非均匀类型的金属——才会产生屈服点。如果屈服后应力降低,可区分上屈服点和下屈服点。流量曲线突然下降时的荷载称为上屈服点。流量曲线上显示的恒定载荷为较低屈服点。(屈服强度,屈服应力,Rel)在不断增加的载荷下,物体发生永久(塑性)变形(屈服)时的应力。在某些材料中,会出现屈服点现象,即应力在初始屈服时下降,随着应变进一步增加,塑性变形继续,而应力没有增加。屈服准则是在多轴载荷下产生屈服的正应力和剪应力的组合。
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。
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。
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。
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。
Ultimate strength 极限应力 The maximum tensile strength a bolt or material can support prior to rupture. Always found in the plastic region of the stress–strain or force–elongation curve, and so is not a design strength. Also called Tensile strength and ultimate tensile strength. The maximum stress (tensile, compressive, or shear) a material can sustain without fracture, determined by dividing maximum load by the original cross-sectional area of the specimen. Also known as nominal strength or maximum strength.
螺栓或材料在断裂前可支撑的最大抗拉强度。总是出现在应力-应变或力-伸长率曲线的塑性区域,因此不是设计强度。也称为抗拉强度和极限抗拉强度。材料在不断裂的情况下能够承受的最大应力(拉伸、压缩或剪切),通过将最大载荷除以试样的原始横截面积来确定。也称为标称强度或最大强度。
Crack-extension resistance (KR) 抗裂扩展性(KR) A measure of the resistance of a material to crack extension, expressed in terms of the stress-intensity factor, the crack-extension force, or values of Jderived using the J-integral concept.
材料对裂纹扩展的抵抗力的量度,以应力强度因子、裂纹扩展力或使用J积分概念导出的J值表示。
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