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Sampling 抽样 The process of measuring a series of values of a time-varying quantity.
测量一系列时变量值的过程。
Fatigue test 疲劳测试 A method for determining the range of alternating (fluctuating)stresses a material can withstand without failing.
一种确定材料可以承受而不会失效的交变(波动)应力范围的方法。
Total head (hT) (Unit m) 总水头(hT)(单位:m) Total pressure pT expressed in terms of the vertical height of a column of liquid, typically water or mercury, i.e. hT = pT/ρg where g is the acceleration due to gravity and ρ is the liquid density.
总压力pT以液体柱(通常为水或汞)的垂直高度表示,即hT=pT/ρg,其中g为重力加速度,ρ为液体密度。
GGas turbine G燃气轮机 An engine in which air, compressed by a multi-stage axial compressor and/or one or more centrifugal compressors, flows into a combustion chamber (or chambers) where fuel is burned and the hot gases then drive an axial turbine which powers the compressor.
由多级轴流压缩机和/或一个或多个离心压缩机压缩的空气流入燃烧室(或多个燃烧室),在燃烧室中燃烧燃料,然后热气体驱动轴流涡轮,为压缩机提供动力。
Clearance volume 余隙容积 (Unit m³) The ‘dead’ volume above a piston, including the recess in the cylinder head, in a reciprocating compressor or engine when the piston is at top dead centre.
(单位m³)活塞位于上止点时活塞上方的“死区”体积,包括气缸盖中的凹槽,在往复式压缩机或发动机中。
Scragging machine 刮擦机 1. A machine to test springs by impulsive loading 2. A machine to increase the service life of coil springs by compressing them to their minimum solid length before use, thereby inducing favourable residual stresses.
1.一种通过冲击载荷测试弹簧的机器2.一种在使用前将螺旋弹簧压缩至其最小实心长度以提高其使用寿命的机器,从而产生有利的残余应力。
Submerged-electrode furnace 浸入式电极炉 A furnace used for liquid carburizing of parts by heating molten salt baths with the use of electrodes submerged in the ceramic lining.
一种通过使用浸入陶瓷衬里中的电极加热熔融盐浴对零件进行液体渗碳的炉。
Chilled castings 冷铸件 Iron castings cooled at a rate that results in white iron (slow enough to avoid the formation of martensite, yet fast enough to prevent any silicon present from causing decomposition of cementite into iron and graphite).
铸铁件以产生白口铁的速度冷却(足够慢以避免形成马氏体,但足够快以防止任何存在的硅导致渗碳体分解成铁和石墨)。
Reverse engineering 逆向工程 The disassembly of a machine, mechanism, system or device, measurement of its component parts, and identification of the materials used so that if required, a functioning replica can be produced.
拆卸机器、机构、系统或装置,测量其组成部分,并识别所用材料,以便在需要时可以生产出功能正常的复制品。
Planar anisotropy 平面异向性 A variation in physical and/or mechanical properties with respect to direction within the plane of material in sheet form.
在片状材料平面内,物理和/或机械性能相对于方向的变化。
Valve 阀门 Any of various manual or automatic devices that are able to initiate, regulate, or stop the flow of a fluid through a conduit or from a closed container.
任何一种手动或自动装置,能够启动、调节或停止通过导管或封闭容器的流体流动。
Breaking load 断裂载荷 The maximum load (or force) applied to a test specimen or structural member loaded to rupture.
施加到加载到破裂的试样或结构构件上的最大载荷(或力)。
Combustion 燃烧氧化 An exothermic chemical reaction in which a fuel and an oxidant, typically air, react together to release a significant quantity of thermal energy in the presence of a flame. In the case of fluid fuels, ignition may be from an electric spark or compression of the
一种放热化学反应,其中燃料和氧化剂(通常是空气)一起反应,在火焰存在的情况下释放大量热能。
Steady loads 稳定负载 Loads that do not change in intensity or that change so slowly they may be regarded as steady.
强度不变或变化缓慢的荷载可视为稳定荷载。
Precision 精确 The closeness of agreement between the results of individual replicated measurements or tests. The standard deviation of the error of measurement may be used as a measure of “imprecision.”
单个重复测量或测试结果之间的一致性。测量误差的标准偏差可用作“不精确性”的度量
Bias pressure (Unit Pa) 偏压(单位Pa) In a fluidic device controlled by pressure difference, the magnitude of that difference.
在由压力差控制的流体装置中,该差值的大小。
Torque coefficient 扭矩系数 1. (KT) For a propeller of diameter D, a non-dimensional parameter defined by KT = T/ρΩ2D5 where Ω is the rotational speed (in rad/s) and ρ is the fluid density. 2. (CT) An alternative to (1) for a wind turbine, defined by CT = 2T/ρV2AR where V is the wind speed, A is the swept area of the blades, and R is the blade radius. 3. (K) An empirical coefficient used to calculate the torque T required to achieve an axial load F in a bolt according to T = KFd where d is the nominal bolt diameter.
1.(KT)对于直径为D的螺旋桨,由KT=T/ρΩ2D5定义的无量纲参数,其中Ω是转速(单位为rad/s),ρ是流体密度。2.(CT)对于风力涡轮机(1)的替代方案,由CT=2T/ρV2AR定义,其中V是风速,a是叶片的扫掠面积,R是叶片半径。3.(K)经验系数,用于根据T=KFd计算螺栓中实现轴向载荷F所需的扭矩T,其中d是螺栓标称直径。
Compressible flow 可压缩流动 A gas flow in which the Mach number M is sufficiently high for the gas density to change significantly. For air, this is when M > 0.3.
马赫数M高到足以使气体密度发生显着变化的气流。对于空气,这是当M>0.3时。
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。
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。
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。
Scratch hardness 划痕硬度 The resistance of a material, such as a metal, alloy, plastic, or mineral, to scratching by a much harder indenter, such as a diamond stylus, moved slowly across the surface. The scratch hardness number is computed from the loads and the dimensions of the residual scratch.
一种材料(如金属、合金、塑料或矿物)对更硬的压头(如金刚石触针)划伤的抵抗力,在表面上缓慢移动。根据载荷和残余划痕的尺寸计算划痕硬度值。
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。
Static fatigue 静态疲劳 A term referring to a time-dependent reduction in strength with a static (noncyclic) load. The term may refer to hydrogen-induced delayed cracking or the effect of creep on the strength of plastics. Delayed fracture caused by environmental effects under dead-weight loading of materials such as glass. The name is unfortunate, as cyclic loads are not involved and glass is not susceptible to fatigue.
指静态(非循环)载荷下强度随时间变化的降低。该术语可指氢致延迟开裂或蠕变对塑料强度的影响。在玻璃等材料的自重荷载下,由环境影响引起的延迟断裂。
Vacuum pump 真空泵 A pump for exhausting air and non-condensable gases from a vessel to be maintained at sub-atmospheric pressure. The pirani and thermal-conductivity gauges are vacuum gauges used to measure the absolute pressure within a vacuum system (vacuum level), usually expressed in torr or Pa.
用于从容器中排出空气和不凝性气体以保持在亚大气压的泵。皮拉尼和热导率计是用于测量真空系统内绝对压力(真空水平)的真空计,通常用托或帕表示。
Acid rain 酸雨 Any form of precipitation, including rain, snow, sleet, fog, dew, and particulates, which contains higher than normal levels of sulfuric and nitric acids. These acids result from natural and man-made emissions of sulfur dioxide and oxides of nitrogen, respectively. Acid soot consists of unburned carbon particles, typically larger than 10 μm, in the atmosphere contaminated with sulfuric acid. The particles result from poor combustion of fossil fuels.
任何形式的降水,包括雨、雪、雨夹雪、雾、露水和颗粒物,其中含有高于正常水平的硫酸和硝酸。这些酸分别来自二氧化硫和氮氧化物的自然排放和人为排放。酸烟灰由未燃烧的碳颗粒组成,通常大于10微米,在被硫酸污染的大气中。这些颗粒是化石燃料燃烧不良造成的。
Differential heating 差动加热 Heating that intentionally produces a temperature gradient within an object such that, after cooling, a desired stress distribution or variation in properties is present within the object.
加热有意在物体内产生温度梯度,从而在冷却后,在物体内出现所需的应力分布或特性变化。
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。
Clevis U形夹 A U-shaped hook with holes at the ends through which a retaining bolt or pin (clevis pin) passes.
一种U形钩,末端有孔,固定螺栓或销(U形销)穿过这些孔。
Temper embrittlement 回火脆化 Brittleness that results when certain steels are held within, or are cooled slowly through, a certain range of temperature below the transformation range. The brittleness is manifested as an upward shift in ductile-to-brittle transition temperature but only rarely produces a low value of reduction in area in a smooth-bar tension test of the embrittled material. The anomalous reduction in toughness of martensitic stainless steels when tempered in the range 370–600°C. Embrittlement of alloy steels caused by holding within or cooling slowly through a temperature range just below the transformation range. Embrittlement is the result of the segregation at grain boundaries of impurities such as arsenic, antimony, phosphorus, and tin; it is usually manifested as an upward shift in ductile-to-brittle transition temperature. Temper embrittlement can be reversed by retempering above the critical temperature range, then cooling rapidly.
当某些钢保持在低于转变范围的某一温度范围内或缓慢冷却时产生的脆性。脆性表现为延性到脆性转变温度的向上移动,但在脆性材料的平滑棒材拉伸试验中,很少产生较小的面积减小值。马氏体不锈钢在370–600°C范围内回火时的韧性异常降低。合金钢的脆化是由于在低于转变范围的温度范围内保持或缓慢冷却而引起的。脆化是杂质(如砷、锑、磷和锡)在晶界处偏析的结果;它通常表现为韧脆转变温度的上升。回火脆化可以通过在临界温度范围以上重新回火,然后快速冷却来逆转。
Cathode 阴极 That electrode in a battery or corrosion cell which attracts electrons.
电池或腐蚀电池中吸引电子的电极。
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。
Cotter pin 开口销 (cotter) 1. A tapered wedge or pin passing through a tapered slot or hole in one member and bearing against a second member to fix it in location. 2. A split cotter is commonly called a split pin. A pin with two legs. With legs together, the pin is placed through the hole in a clevis pin. The legs are then opened outward to prevent the cotter pin from backing out of the hole. The cotter pin, in turn, prevents the load-bearing clevis pin from backing out of its retaining hole.
(开口)1.锥形楔子或销钉穿过一个构件中的锥形槽或孔,并支撑在第二个构件上以将其固定到位。2.开口开口通常称为开口销。相当于有两条腿的别针,将支腿放在一起,销钉穿过U形夹销上的孔。然后将支腿向外打开以防止开口销从孔中退出。开口销反过来防止承重U形夹销从其固定孔中退出。
Octane number 辛烷值 (octane rating) A measure of the anti-knock properties of a fuel taken as the percentage by volume of iso-octane in the fuel.
(辛烷值)以燃料中异辛烷的体积百分比表示的燃料抗爆性能的量度。
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。
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。
Sample average 样本平均值 The sum of all the observed values in a sample divided by the sample size. It is a point estimate of the population mean. Also known as arithmetic mean.
样本中所有观察值的总和除以样本大小。它是总体平均值的点估计。也称为算术平均值。
Creep–time relations 蠕变时间关系 Algebraic or numerical relations between creep strain and time at constant stress.
恒定应力下蠕变应变与时间之间的代数或数值关系。
Actual cubic feet per minute 实际立方英尺每分钟 (acfm) An obsolete (i.e. non-SI) measure of volumetric flow rate; the volume of a gas flowing per minute at actual operating pressure and temperature, as opposed to the corresponding volume flow rate at STP.
(acfm)已被淘汰的(即非SI)体积流量测量;在实际工作压力和温度下每分钟流动的气体体积,与STP下的相应体积流量相反。
Shear stress (Unit Pa) 剪应力(单位Pa) (1) A stress that exists when parallel planes in metal crystals slide across each other. (2) The stress component tangential to the plane on which the forces act. Also known as tangential stress. (shearing stress, tangential stress, τ) 1. The stress which acts parallel to any plane within a solid material. It can arise due to a bending moment, a shear force, or torque applied to the body. 2. The stress corresponding to velocity gradients within a flowing viscous fluid.
(剪应力,切向应力,τ)(1)当金属晶体中的平行平面彼此滑动时存在的应力。(2)与力作用平面相切的应力分量。也称为切向应力。1.平行于固体材料内任何平面的应力。它可能是由于施加在身体上的弯矩、剪力或扭矩引起的。2.对应于流动粘性流体内的速度梯度的应力。
Spring 弹簧 An elastic component which stores mechanical energy and exerts a force when deformed. The slope of the curve of applied force F to the deflexion of a spring x, dF/dx, is termed the spring rate or spring modulus k with unit N/m. For a linear spring, the F(x) curve is proportional and k is called the spring constant. An elastic device which yields under stress or pressure but returns to its original state or position when the stress or pressure is removed.
储存机械能并在变形时施加力的弹性部件。作用力F与弹簧x偏转的曲线斜率dF/dx称为弹簧率或弹簧模量k,单位为N/m。对于线性弹簧,F(x)曲线成比例,k称为弹簧常数。一种弹性装置,在应力或压力下屈服,但在应力和压力消除后恢复到其原始状态或位置。
Thermomechanical working 热机械加工 A general term covering a variety of processes combining controlled thermal and deformation treatments to obtain specific properties. Same as thermal-mechanical treatment.
一个通用术语,涵盖结合受控热处理和变形处理以获得特定性能的各种工艺。与热机械处理相同。
Modulus of rupture 断裂模量 Nominal stress at fracture in a bend test or torsion test. In bending, modulus of rupture is the bending moment at fracture divided by the section modulus. In torsion, modulus of rupture is the torque at fracture divided by the polar section modulus.
弯曲试验或扭转试验中的标称断裂应力。在弯曲中,断裂模量是断裂时的弯矩除以截面模量。在扭转中,断裂模量是断裂时的扭矩除以极截面模量。
Acoustic power 声功率 (sound power) (Unit W) The rate of flow of acoustic energy across a specified surface.
(声功率)(单位W)声能流过指定表面的速率。
Gauge pressure (Unit Pa) 表压(单位Pa) The level of static pressure above the ambient pressure.
高于环境压力的静压水平。
Elastic energy 弹性能 The amount of energy required to deform a material within its elastic range of behavior, neglecting small heat losses due to internal friction. The energy absorbed by a specimen per unit volume of material contained within the gage length being tested. It is determined by measuring the area under the stress-strain curve up to a specified elastic strain. See also modulus of resilience and strain energy.
材料在其弹性行为范围内变形所需的能量,忽略因内耗引起的小热损失。试样在被测标距内每单位体积材料吸收的能量。它是通过测量应力-应变曲线下达到规定弹性应变的面积来确定的。另见弹性模量和应变能。
Densimeter 密度计 An instrument used to determine the density or relative density of a solid or liquid.
用于测定固体或液体的密度或相对密度的仪器。
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。
Bolt gage 螺栓量规 An ultrasonic instrument used to measure the stress or strain in bolts.
用于测量螺栓应力或应变的超声波仪器。
Thermoelastic effect 热弹性效应 The change in temperature of material under adiabatic elastic deformation, e.g. when loading is so rapid that the material is not in thermal equilibrium with its surroundings. For most materials, elastic tension lowers the temperature and compression raises it. The reverse occurs in elastomers such as rubber that exhibit entropic elasticity because stretching reduces the number of possible molecular configurations and so reduces the entropy. The thermoelastic effect gives rise to a stress–strain hysteresis loop in cyclic elastic loading and is one mechanism by which vibrational energy is dissipated internally in materials.
材料在绝热弹性变形下的温度变化,例如当加载速度如此之快,以至于材料与其周围环境不处于热平衡时。对于大多数材料,弹性张力降低温度,压缩提高温度。相反的情况发生在弹性体中,如橡胶,其表现出熵弹性,因为拉伸减少了可能的分子构型的数量,从而降低了熵。热弹性效应在循环弹性载荷中产生应力-应变迟滞回线,是振动能量在材料内部耗散的一种机制。
Absolute value error 绝对值误差 The magnitude of the error dlsregarding the algebraic sign, or, for a vectorial error, disregarding its function.
关于代数符号的误差幅度,或者,对于矢量误差,不考虑其函数。
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。
Waviness 波纹度 Waviness is periodic deviations from geometric surface, often sinusoidal in form and often determined by low-level oscillations of the machine-tool-workpiece system during machining. Typically, wavelengths range from 1 to 10 mm (0.04 to 0.4 in.) and wave heights from a few to several hundred micrometers.
波纹度是与几何表面的周期性偏差,其形式通常是正弦的,通常由机床-工件系统在加工过程中的低水平振荡决定。通常,波长范围为1至10毫米(0.04至0.4英寸),波高范围为几微米至几百微米。
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。
Condensing boiler 冷凝锅炉 A relatively small industrial or domestic boiler that burns sulfur-free natural gas so that the products of combustion do not contain sulfuric acid and can be allowed to condense on heat-transfer surfaces without danger of corrosion.
一种相对较小的工业或家用锅炉,燃烧无硫天然气,因此燃烧产物不含硫酸,并且可以在传热表面上冷凝而没有腐蚀的危险。
Mechanical metallurgy 机械冶金 The science and technology dealing with the behavior of metals when subjected to applied forces.
处理金属在外力作用下的行为的科学技术。
Air conditioning 空调 The process of controlling the temperature and humidity in rooms, buildings, aircraft, passenger vehicles, etc. More generally it includes control of dust, levels of radiant heat, etc.
控制房间、建筑物、飞机、客运车辆等的温度和湿度的过程。更一般地说,它包括控制灰尘、辐射热水平等。
Gamma iron 加马铁 The face-centered cubic form of pure iron, stable from 910 to 1400 °C (1670 to 2550 °F).
纯铁的面心立方形式,在910至1400°C(1670 2550°F)温度范围内稳定。
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。
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。
Grain growth 晶粒生长 An increase in the average size of the grains in polycrystalline metal, usually as a result of heating at elevated temperature.
多晶金属中晶粒平均尺寸的增加,通常是高温加热的结果。
Ballonet 气囊 An airbag used in a hybrid airship. Helium gas expels air from the ballonet during ascent. Fans draw air in during descent.
混合动力飞艇中使用的安全气囊。氦气在上升过程中将空气从气囊中排出。风扇在下降过程中吸入空气。
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。
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 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。
Aerated bath nitriding 空气搅拌液体渗氮法 A type of liquid nitriding in which air is pumped through the molten bath creating agitation and increased chemical activity.
一种液体氮化,其中空气被泵入熔池,产生搅拌并增加化学活性。
Sample variance (s²) 样本方差(s²) The sum of the squares of the differences between each observed value and the sample average divided by the sample size minus one. It is a point estimate of the population variance.
每个观测值与样本平均值之差的平方和除以样本大小减1。它是总体方差的点估计。
Thread rolling 滚丝 Thread rolling (also known as roll threading) is a cold forming process for producing threads or other helical or annular forms by rolling the impression of hardened steel dies into the surface of a cylindrical or conical blank. Polygonal blanks are also thread rolled for the purpose of fabricating thread-forming and self-locking screws. The preferred polygonal shape is trilobular and is produced in flat die machines.
螺纹滚压(也称为滚压螺纹)是一种冷成型工艺,通过将硬化钢模具的压痕滚压到圆柱形或锥形坯料的表面来生产螺纹或其他螺旋或环形形状。多边形坯料也进行螺纹轧制,以制造螺纹成型和自锁螺钉。优选的多边形形状为三棱形,并在平模机中生产。
British thermal unit (BTU, Btu) 英热单位(BTU,Btu) An obsolete (non-SI) imperial unit of energy defined as the energy required to raise the temperature of one pound of pure water at 68°F by 1°F. The conversion to SI is 1 Btu = 1.055 056 × 103 J.
一种已被淘汰的(非SI)英制能量单位,定义为将68°F的一磅纯水的温度升高1°F所需的能量。转换为SI为1Btu=1.055056×103J。
Shear fracture 剪切断裂 A ductile fracture in which a crystal (or a polycrystalline mass)has separated by sliding or tearing under the action of shear stresses. Contrast with cleavage fracture.
在剪切应力作用下,晶体(或多晶块)通过滑动或撕裂而分离的韧性断裂。与解理断裂形成对比。
Radioactive heat (Unit J) 放射性热(单位J) Thermal energy released from the nucleus of an atom such as uranium235 by fission due to the absorption of a neutron. Heat is also produced by radioactive decay.
铀235等原子核因吸收中子而裂变释放的热能。放射性衰变也会产生热量。
Proof load 验证载荷(单位 N) The maximum, safe, static, tensile load which can be placed on a fastener without yielding it. Sometimes given as a force (in lb or N) sometimes as a stress (in psi or MPa). The test load in quality control to which different components made of different materials must be subjected without failing in order to perform properly.
可施加在紧固件上而不使其屈服的最大安全静态拉伸载荷。有时以力(lb或N)表示,有时以应力(psi或MPa)表示。质量控制中的测试负荷,由不同材料制成的不同部件必须经受该负荷,才能正常运行。
Milling 铣削 A machining process, typically for metals and plastics, in which a multi-tooth rotary cutter removes material to produce flat or profiled surfaces, slots, grooves, etc. Milling is a machining process in which metal is removed by a rotating multiple-tooth cutter; each tooth removes a small amount of metal with each revolution of the spindle. Because both workpiece and cutter can be moved in more than one direction at the same time, surfaces having almost any orientation can be machined.
一种加工工艺,通常用于金属和塑料,其中多齿旋转刀具去除材料以产生平坦或异形表面、槽、槽等。金属由旋转多齿刀具去除;主轴每转一圈,每个齿都会去除少量金属。因为工件和刀具可以同时在多个方向上移动,所以几乎可以加工任何方向的表面。
Tensile test (tension test) 拉伸试验(拉力试验) A test in which a precisely-machined tensile specimen (tensile testpiece), typically circular or rectangular in cross section with large end sections that are gripped in the testing machine, is subjected to an increasing tensile load, usually to the point of fracture, to produce a stress–strain curve from which such material properties as modulus of elasticity, limit of proportionality, proof stress, yield point, and ultimate tensile stress can be determined. The relevant standard is ISO 6892-1.
一种试验,在这种试验中,精密加工的拉伸试样(拉伸试件)的横截面通常为圆形或矩形,具有在试验机中夹紧的大端部,受到越来越大的拉伸载荷,通常达到断裂点,以产生应力-应变曲线,从中可以看出弹性模量、比例极限等材料特性,可以确定验证应力、屈服点和极限拉伸应力。相关标准为ISO 6892-1。
Uniform strain 均匀应变 The strain occurring prior to the beginning of localization of strain (necking); the strain to maximum load in the tension test.
在应变局部化(颈缩)开始之前发生的应变;拉伸试验中最大载荷的应变。
Strain hardening 应变硬化 An increase in hardness and strengthcaused by plastic deformation at temperatures below the recrystallization range. Also known as work hardening. (workhardening) The increase in stress above the initial yield stress required to deform a metal to greater strains in the plastic range at temperatures below the recrystallization range (cold working). Unloading after some strain or work input gives a harder and stronger material.
在低于再结晶范围的温度下,塑性变形导致硬度和强度的增加。也称为加工硬化。(加工硬化)在低于再结晶范围(冷加工)的温度下,使金属在塑性范围内变形至更大应变所需的高于初始屈服应力的应力增加。在一定的应变或功输入后卸载,会得到更硬、更强的材料。
Actual power 实际功率 (actual horsepower) (Unit W or hp) The power delivered at the output shaft of an engine, before subsequent transmission through a gearbox etc.
(实际马力)(单位W或hp)在随后通过变速箱等传输之前,在发动机输出轴上传递的功率。
Ideal gas laws 理想气体定律 The law relating pressure, temperature and volume of an ideal (perfect) gas pV = mRT, where R is the gas constant. The law implies that at constant temperature T, the product of pressure p and volume V is constant (Boyle’s law), and at constant pressure, the volume is proportional to the temperature (Charles’ law).
与理想(完美)气体的压力、温度和体积相关的定律pV=mRT,其中R是气体常数。该定律意味着在恒定温度T下,压力p和体积V的乘积是恒定的(波义耳定律),而在恒定压力下,体积与温度成正比(查尔斯定律)。
Apparent area of contact 表观接触面积 In tribology, the area of contact between two solid surfaces defined by the boundaries of their macroscopic interface.
在摩擦学中,两个固体表面之间的接触区域由其宏观界面的边界定义。
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。
Heat tinting 热着色 Coloration of a metal surface through oxidation by heating to reveal details of the microstructure.
通过加热氧化使金属表面着色,以揭示微观结构的细节。
Superheating 过热 Heating above the temperature at which an equilibrium phase transformation should occur without actually obtaining the transformation.
在不实际获得相变的情况下,加热到应发生平衡相变的温度以上。
Repeatability 重复性 A term used to refer to the test-result variability associated with a limited set of specifically defined sources of variability within a single laboratory.
一个术语,用于指与单个实验室内一组有限的特定变异源相关的测试结果变异性。
Magnetic materials 磁性材料 Materials in which the magnetic moment of adjacent atoms can adopt either parallel or antiparallel alignment. Ferromagnetism occurs when the magnetic moments adopt parallel alignment. When adjacent magnetic moments cancel due to antiparallel alignment, the material exhibits antiferromagnetism and has no overall magnetic moment. Examples of the latter include ferrous oxide and manganese oxide. The phenomenon of ferrimagnetism occurs when adjacent magnetic moments adopt antiparallel alignment but have unequal magnitude. The region of ferromagnetic or ferrimagnetic material in which the magnetic moments are aligned is known as a magnetic domain and adjacent regions are separated by domain walls. Diamagnetic and paramagnetic materials exhibit weak forms of magnetism that results from independent (uncoupled) alignment of magnetic atomic dipoles induced by an applied magnetic field. Ferromagnetic and ferrimagnetic materials can acquire high degrees of magnetization in relatively weak magnetic fields. They have different hysteresis characteristics and are classified as either hard magnets or soft magnets. Hard magnets retain large magnetization in the absence of an applied magnetic field and are used as permanent magnets. Conventional materials include magnet steels alloyed with tungsten or cobalt. Rare-earth magnets made from alloys of rare-earth elements produce significantly stronger magnetic fields. The most common of these are samarium-cobalt and neodymiumiron-boron permanent magnets. Their strength allows them to be small and used in numerous applications, including cordless tools, disk drives, headphones, toys, and motors for automotive components such as wipers, fans, washers, and windows. Soft magnets may be magnetized and demagnetized relatively easily. When subjected to an alternating magnetic  field the energy loss due to hysteresis is small. Common materials include iron-silicon alloys (known as electrical steels), nickel-iron alloys (permalloy), soft ferrites, and amorphous nanocrystalline alloys, the last of which can be produced in the form of tape by meltspinning. Soft magnets are used to enhance the magnetic flux produced by an electric current.
相邻原子的磁矩可以采用平行或反平行排列的材料。当磁矩采用平行排列时,会产生铁磁性。当相邻磁矩因反平行排列而抵消时,材料表现出反铁磁性,没有总磁矩。后者的实例包括氧化亚铁和氧化锰。当相邻磁矩采用反平行排列但大小不等时,就会出现铁磁现象。磁矩对齐的铁磁或铁磁材料区域称为磁畴,相邻区域由磁畴壁分隔。抗磁和顺磁材料表现出弱磁性形式,这是由外加磁场诱导的磁原子偶极子的独立(非耦合)排列引起的。铁磁性和铁磁性材料可以在相对弱的磁场中获得高磁化度。它们具有不同的磁滞特性,分为硬磁铁和软磁铁。硬磁铁在没有外加磁场的情况下保持较大的磁化强度,用作永磁体。常规材料包括与钨或钴合金化的磁钢。由稀土元素合金制成的稀土磁体产生明显更强的磁场。其中最常见的是钐钴和钕硼永磁体。它们的强度使其体积小,可用于多种应用,包括无绳工具、磁盘驱动器、耳机、玩具和汽车部件(如雨刷、风扇、洗衣机和车窗)的电机。软磁体可以相对容易地磁化和退磁。当受到交变磁场时,由于磁滞引起的能量损失很小。常见材料包括铁硅合金(称为电工钢)、镍铁合金(坡莫合金)、软铁氧体和非晶纳米晶合金,最后一种可以通过熔钉以胶带的形式生产。软磁铁用于增强电流产生的磁通量。
Carbon restoration 碳修复 Replacing the carbon lost in the surface layer from previous processing by carburizing this layer to substantially the original carbon level. Sometimes called recarburizing.
通过将该层渗碳到基本上原始的碳水平来替换先前处理中在表面层中损失的碳。有时称为再碳化。
Coupling 耦合 A detachable mechanism forming a joint. A connector of two components of a joint. 1. Any mechanical fastening connecting two or more shafts, or parts of a mechanism, in order to transmit power. 2. A device for connecting two vehicles.
一种形成关节的可拆卸机构。关节的两个组件的连接器。1.连接两个或多个轴或机构部件的任何机械紧固件,以传递动力。2.连接两辆车的装置。
Stress cracking 应力开裂 A family of failure modes, each of which involves high stress and chemical action. The family includes Hydrogen embrittlement, Stress corrosion cracking, stress embrittlement, and hydrogen-assisted stress corrosion.
一系列失效模式,每种模式都涉及高应力和化学作用。该系列包括氢脆、应力腐蚀开裂、应力脆化和氢辅助应力腐蚀。
Tear strength (Unit N/m) 撕裂强度(单位:N/m) The tensile force divided by the sheet thickness required to tear a pre-split sheet material at a specified rate. Particularly used for plastics, rubber, fabrics, and elastomers. Since the units are not those of stress but equivalent to J/m², the units of toughness, the term ‘strength’ is strictly incorrect.
按规定速率撕裂预裂片材所需的张力除以片材厚度。特别用于塑料、橡胶、织物和弹性体。由于单位不是应力单位,而是相当于J/m²,韧性单位,“强度”一词是完全错误的。
Surface hardening 表面硬化 A generic term covering several processes applicable to a suitable ferrous alloy that produces, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are carbonitriding, carburizing, induction hardening, flame hardening, nitriding, and nitrocarburizing. Use of the applicable specific process name is preferred.
一个通用术语,涵盖适用于仅通过淬火硬化产生比型芯更硬或更耐磨的表面层的合适铁合金的几种工艺。表面层的化学成分没有显著改变。常用的工艺有碳氮共渗、渗碳、感应淬火、火焰淬火、氮化和氮碳共渗。最好使用适用的特定工艺名称。
Form of thread 螺纹形式 The profile of a thread in an axial plane for a length of one pitch.
一个螺距长度的螺纹在轴向平面中的轮廓。
Outside diameter (Unit m) 外径(单位:m) (external diameter, OD) The diameter of a circular cylindrical tube or a sphere measured between opposite points on the external surface.
(外径,OD)在外表面上的相对点之间测量的圆柱管或球体的直径。
Turning angle (θ) 转向角(θ) The change in direction experienced by a gas flow passing through an oblique shock wave or Prandtl–Meyer expansion fan.
气流通过斜激波或Prandtl–Meyer膨胀风机时所经历的方向变化。
Machine tool 机床工具 A powered machine, such as a borer, grinder, lathe, milling machine or planer, used for cutting and shaping metal, plastics, composites, etc. (machining). A machining centre is a CNC machine tool working about several axes, having a stock of tools and automatic tool changing ability, which is capable of diverse machining operations under automated control.
一种动力机器,如钻孔机、磨床、车床、铣床或刨床,用于切割和成形金属、塑料、复合材料等(机加工)。加工中心是围绕多个轴工作的CNC机床,具有刀具库存和自动换刀能力,能够在自动化控制下进行各种加工操作。
Strength of materials 材料强度 A confusing name for what is really stress analysis, reflecting older engineering design based upon elasticity and ‘theories of strength’ for different materials, without regard to cracks.
对于真正的应力分析,这是一个具有迷惑性的名称,反映了基于弹性和不同材料的“强度理论”的旧工程设计,而不考虑断裂。
Dimensional stability 尺寸稳定性 Ability of a plastic part to retain the precise shape in which it was molded, fabricated, or cast.
塑料零件保持其成型、制造或铸造时的精确形状的能力。
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。
Dynamic load rating (Unit N) 额定动载荷(单位N) The allowable load on a component or structure when the loading is not static.
当负载不是静态时,组件或结构上的允许负载。
Heat balance (heat budget) 热平衡(热预算) An energy balance involving only heat transfer across the system boundary and the stored energy.
仅涉及跨系统边界的热传递和存储能量的能量平衡。
Fillet 圆角 Transition region between bolt head and shank, or between other changes in diameter.
螺栓头和螺栓杆之间的过渡区域,或其他直径变化之间的过渡区域。
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。
Inch-pound force/inch² 英寸磅力/英寸² A non-SI unit for the specific work of fracture (fracture toughness). The conversion to SI is 1 in.lbf/in² = 1.751 268 × 102 J/m².
用于特定断裂功(断裂韧性)的非国际单位制单位。到SI的转换为1英寸。lbf/in²=1.751268×102J/m²。
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。
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。
Supercooling 过冷 Cooling below the temperature at which an equilibrium phase transformation can take place, without actually obtaining the transformation.
在没有实际获得相变的情况下,冷却到可以发生平衡相变的温度以下。
Total carbon 总碳 The sum of the free and combined carbon (including carbon in solution) in a ferrous alloy.
铁合金中游离碳和结合碳(包括溶液中的碳)的总和。
Size effect 尺寸效应 Effect of the dimensions of a piece of metal on its mechanical and other properties and on manufacturing variables such as forging reduction and heat treatment. In general, the mechanical properties are lower for a larger size.
金属件的尺寸对其机械和其他性能以及对制造变量(如锻造、压下和热处理)的影响。一般来说,尺寸越大,机械性能越低。
Salt-velocity meter 盐速计 A volume flow meter based on detecting the transit time for a small quantity of salt or radioactive isotope in a flow by measuring electrical conductivity or radiation level.
一种体积流量计,通过测量电导率或辐射水平来检测流量中少量盐或放射性同位素的渡越时间。
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。
Shrink ring 预紧环 A ring, which is expanded by heating, is placed around an assembly of parts, and then contracts upon cooling to hold the assembly in place.
通过加热膨胀的环被放置在零件组件周围,然后在冷却时收缩以将组件固定到位。
Nut thickness 螺母厚度 The nut thickness shall be the overall distance measured parallel to the axis of nut, from the top of the nut to the bearing surface, and shall include the thickness of the washer face where provided.
螺母厚度应为平行于螺母轴线测量的从螺母顶部到轴承表面的总距离,还应包括垫圈表面的厚度。
Arbitration bar 抗弯试棒 A test bar, cast with a heat of material, used to determine chemical composition, hardness, tensile strength, and deflection and strength under transverse loading in order to establish the state of acceptability of the casting.
用热材料铸造的测试棒,用于确定化学成分、硬度、抗拉强度、横向载荷下的挠度和强度,以确定铸件的可接受状态。
Bolt blank 螺栓毛坯 A rod on which a head has been formed, but on which no thread has been cut, from which bolts or screws may be made as required.
一种已形成头部但未切割螺纹的杆,可根据需要从中制造螺栓或螺钉。
Stiffness 刚度 (1) The ability of a metal or shape to resist elastic deflection.(2) The rate of stress increase with respect to the rate of increase in strain induced in the metal or shape; the greater the stress required to produce a given strain, the stiffer the material is said to be.
(1)金属或形状抵抗弹性变形的能力。(2)所述应力增加速率相对于在所述金属或形状中诱导的应变增加速率;产生给定应变所需的应力越大,材料就越硬。
Load factor (F) 负载系数(F) The ratio between an increase in bolt tension and the external load which has caused the increase. Factors reflecting the probability of an increase in load in a shear joint. Used in load and resistant factor design.
螺栓张力增加与导致增加的外部载荷之间的比率。反映剪切接缝中荷载增加概率的系数。用于载荷和阻力系数设计。
Mole (mol) 摩尔(mol) The base unit of the amount of substance in the SI system. It was previously defined as the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kg of carbon-12. From 20 May 2019 it has been defined as the amount of substance containing exactly 6.022 140 76 × 1023 elementary entities.
SI国际单位制中物质量的基本单位。此前,它被定义为一个系统中的物质量,该系统包含的基本实体数量与0.012千克碳-12中的原子数量相同。从2019年5月20日起,它已被定义为包含6.02214076×1023个基本实体的物质量。
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。
Natural aging 自然时效 Spontaneous aging of a supersaturated solid solution at room temperature.
过饱和固溶体在室温下的自发时效。
Hoseclip 软管夹 (hose clamp) A circular metal band, one end of which has a screw mechanism through which passes the other end such that the screw engages with indentations in the band, allowing the clip to be tightened or loosened. Used to hold a hose on to a pipe such as a water outlet.
(软管夹)一种圆形金属带,其一端有一个螺钉组织,另一端穿过该螺钉组织,使螺钉与带子上的凹口啮合,从而可以拧紧或松开夹子。用于将软管固定在管道上,例如出水口。
Biaxial stress 双轴应力 Generalized loading of a body in a single plane with no loading normal to it.
物体在一个平面内的广义载荷,没有垂直于它的载荷。
Offset yield strength 条件屈服强度 The stress at which the strain exceeds by a specified amount (the offset) an extension of the initial proportional portion of the stress-strain curve. Expressed in force per unit area.
应变超过应力-应变曲线初始比例部分延伸规定量(偏移)的应力。以每单位面积的力表示。
Principal stress (normal) 主应力(正常) The maximum or minimum value of the normal stressat a point in a plane considered with respect to all possible orientations of the considered plane. On such principal planes the shear stress is zero. There are three principal stresses on three mutually perpendicular planes. The state of stress at a point may be: (1) uniaxial, a state of stress in which two of the three principal stresses are zero; (2) biaxial, a state of stress in which only one of the three principal stresses is zero; or (3) triaxial, a state of stress in which none of the principal stresses is zero. Multiaxial stress refers to either biaxial or triaxial stress.
相对于所考虑平面的所有可能方向,所考虑平面中某点处的法向应力的最大值或最小值。在这样的主平面上,剪切应力为零。在三个相互垂直的平面上有三个主应力。一点的应力状态可以是:(1)单轴,三个主应力中的两个为零的应力;(2)双轴,三个主应力中只有一个为零的应力状态;或(3)三轴,即主应力均不为零的应力状态。多轴应力是指双轴或三轴应力。
Biomedical engineering 生物医学工程 The application of engineering principles and methodology to the medical field. Examples involving mechanical engineering include the design and construction of artificial limbs and hearts, heart-lung machines, prosthetic eyes, and orthopaedic implants such as hip joints and pins to stabilize fractured bones.
工程原理和方法在医学领域的应用。涉及机械工程的例子包括假肢和心脏、心肺机、假眼和骨科植入物(如髋关节和用于稳定骨折骨骼的销钉)的设计和建造。
Bearing stress 承受应力 The force per unit of bearing area.
每单位承载面积的力。
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。
Bioenergy 生物能源 1. Energy derived from materials such as purpose-grown energy crops, including sugar cane, maize, wheat, and rice, as well as wood, straw, and animal waste, including sewage, manure, and animal litter. 2. A term sometimes used to cover biomass and biofuels together.
1.来自特定种植的能源作物(包括甘蔗、玉米、小麦和大米)以及木材、稻草和动物粪便(包括污水、粪便和动物垃圾)等材料的能源。2.有时用于同时涵盖生物质和生物燃料的术语。
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。
Absolute specific gravity 绝对比重 The ratio of the weight of any volume of a substance to the weight of an equal volume of a reference substance at the same temperature, often water at 4°C, both measured in a vacuum to avoid any effect of buoyancy.
在相同温度下,任何体积的物质的重量与等体积的参考物质的重量之比,通常是4°C的水,两者都是在真空中测量的,以避免任何浮力的影响。
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。
Structural-integrity analysis 结构完整性分析 Assessment of components and structures for likelihood of failure by buckling, fracture, yielding, etc. under conditions of normal and accident loading.
在正常和事故荷载条件下,评估部件和结构因屈曲、断裂、屈服等而失效的可能性。
Bucket 吊桶 1. A cup-shaped vane with a central dividing ridge attached to the periphery of the runner of an impulse water turbine such as a Pelton turbine. 2. A rotor blade in a compressor or turbine.
1.一种杯形叶片,所述杯形叶片具有附接到冲击式水轮机(例如冲击式水轮机台)的转轮的外围的中央分隔脊。2.压缩机或涡轮机中的转子叶片。
Maraging steels 马氏体时效钢 Very high-strength iron alloys named after ‘martensitic’ and ‘aging’. They contain nickel, chromium, cobalt, and molybdenum, and form martensite on air cooling with a strength of about 1 GPa. When reheated to about 500°C and aged for some hours, a room-temperature strength of some 2.4 GPa is reached.
以“马氏体”和“时效”命名的超高强度铁合金。它们含有镍、铬、钴和钼,在空气冷却下形成强度约为1GPa的马氏体。当再加热至约500°C并老化数小时时,室温强度达到约2.4GPa。
Diesel engine 柴油发动机 (compression–ignition engine) A piston engine operating on the Diesel cycle in which the air is compressed to a temperature above the autoignition temperature of the fuel and combustion is initiated as the fuel is injected into the hot air. Diesel engines operate at higher compression ratios (typically in the range 12 to 24) than petrol engines. Although named after Rudolf Diesel, the inventor, Diesel engine is often spelled with a lower case d, contrary to normal practice.
(压燃式发动机)在柴油循环中运行的活塞式发动机,在该循环中,空气被压缩至高于燃料自燃温度的温度,当燃料喷射到热空气中时,燃烧开始。柴油发动机在比汽油发动机更高的压缩比下运行(通常在12到24的范围内)。虽然以发明人鲁道夫·迪塞尔命名,但迪塞尔发动机通常拼写为小写d,这与正常做法相反。
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。
Absolute viscosity 绝对粘度 A measure of the internal shear properties of fluids, expressed as the tangential force per unit area at either of two horizontal planes separated by one unit thickness of a given fluid, one of the planes being fixed and the other moving with unit velocity.
流体内部剪切特性的量度,表示为两个水平面中的任何一个上的单位面积切向力,两个水平面被给定流体的一个单位厚度隔开,其中一个平面固定,另一个以单位速度移动。
Air classifier 空气分级机 (air elutriator) A device in which an airstream, which may be swirling, sorts particles by a combination of size, shape, and mass.
(空气淘析器)一种装置,在该装置中,气流(可能是漩涡)根据大小、形状和质量的组合对颗粒进行分类。
British Standards Institution (BSI) 英国标准协会(BSI) The Institution in the UK responsible for the preparation and publication of standard specifications (British standards) for manufactured goods, their design, manufacture and testing.
负责为制成品及其设计、制造和测试制定和发布标准规范(英国标准)的英国机构。
Bulk velocity 体积速度 (average velocity, V) (Unit m/s) For fluid flow in a pipe or duct, the average flow velocity, given by V = ṁ/ρA where ṁ is the mass flow rate, ρ is the fluid density, and A is the duct cross-sectional area.
(平均速度,V)(单位m/s)对于管道或管道中的流体流动,平均流速,由V=ṁ/ρA给出,其中ṁ是质量流量,ρ是流体密度,A是管道截面积。
Stability 稳定性 1. A term relating to whether a body, structure, system, or flow is in a state of stable, unstable, or neutral equilibrium. 2. In numerical analysis, whether numerical errors, such as roundoff or input-data errors, are damped, propagate, or cause divergence of the solution as the numerical method proceeds. 3. A control system is often described as stable when a step change in input results in a steady output without continuing oscillation.
1.与物体、结构、系统或流是否处于稳定、不稳定或中性平衡状态有关的术语。2.在数值分析中,随着数值方法的进行,数值误差(如舍入误差或输入数据误差)是否衰减、传播或导致解发散。3.当输入的阶跃变化导致稳定输出而无持续振荡时,控制系统通常被描述为稳定的。
Double-shear test 双剪试验 A shear test having two stationary, shear blades and one moving one and that uses solid round bars as test specimens.
一种剪切试验,具有两个固定的剪切刀片和一个移动的刀片,并使用实心圆棒作为试样。
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。
Concentration ratio 浓度比 For a concentrating solar collector, the ratio of the projected area of the concentrator facing the solar beam to the actual area of the receiver.
对于聚光太阳能集热器,集中器面向太阳光束的投影面积与接收器的实际面积之比。
Grinding stress (Unit Pa) 磨削应力(单位Pa) The residual stresses left in the surface of a component after grinding, owing to non-uniform cooling from the high surface temperatures produced.
由于产生的高表面温度造成的不均匀冷却,磨削后留在部件表面的残余应力。
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。
Accommodation 适应能力 The ability of a robot to respond to changes in the environment.
机器人对环境变化做出反应的能力。
Equilibrium diagram 平衡图 A graphical representation of the temperature, pressure and composition limits of phase fields in an alloy system as they exist under conditions of complete equilibrium. In metal systems, pressure is usually considered constant.
在完全平衡条件下,合金系统中相场的温度、压力和成分极限的图形表示。在金属系统中,压力通常被认为是恒定的。
Quick coupling 快速接头 (quick disconnect, fast coupling) A hose connection allowing rapid assembly or disassembly and comprising a socket and a plug incorporating a springloaded locking mechanism.
(快速断开、快速连接)一种软管连接,允许快速组装或拆卸,包括插座和带有弹簧加载锁定机构的插头。
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。
Cavity radiator 空腔辐射器 A heated chamber having a small hole through which radiation, approximating blackbody radiation, passes out.
具有小孔的加热室,近似于黑体辐射的辐射通过该小孔传递出去。
Full annealing 全退火 An imprecise term that denotes an annealing cycle to produce minimum strength and hardness. For the term to be meaningful, the composition and starting condition of the material and the time-temperature cycle used must be stated. Annealing a ferrous alloy by austenitizing and then cooling slowly through the transformation range.
一个不精确的术语,表示产生最小强度和硬度的退火循环。为了使该术语有意义,必须说明材料的组成和起始条件以及使用的时间-温度循环。通过奥氏体化退火铁合金,然后在转变范围内缓慢冷却。
Isothermal annealing 等温退火 Austenitizing a ferrous alloy and then cooling to and holding at a temperature at which austenite transforms to a relatively soft ferrite carbide aggregate.
将铁合金奥氏体化,然后冷却至奥氏体转变为相对软的铁素体碳化物集合体的温度并保持该温度。
Atomic volume 原子体积 Volume of unit cell per atom.
每个原子的晶胞体积。
Atom 原子 The smallest unit of matter that has the properties of a chemical element. The simplest description of an atom (Bohr model) is of a compact nucleus surrounded by one or more orbiting electrons.
具有化学元素性质的最小物质单位。原子的最简单描述(玻尔模型)是由一个或多个轨道电子包围的致密原子核。
Rubber hardness 橡胶硬度 The indentation hardness of rubber-like materials in which the depth of indentation under load is measured. This is a measure of elastic moduli rather than yield stress as with ductile materials, since there is little, if any, permanent impression remaining on unloading rubbery materials.
测量负载下压痕深度的橡胶类材料的压痕硬度。这是对弹性模量的测量,而不是对韧性材料的屈服应力,因为卸载橡胶材料时几乎没有(如果有的话)永久压痕。
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。
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。
Fog quenching 雾淬 Quenching in a fine vapor or mist.
在细蒸汽或薄雾中淬火。
Joule 焦耳 The SI unit of energy. One joule is the work done by a force of one newton acting over a distance of one metre. The symbol is J, where 1 J = 1 N m.
国际单位制能量单位。一焦耳是一牛顿的力在一米的距离上所做的功。符号为J,其中1j=1m。
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。
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。
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。
Homogenizing 均质化 Holding at high temperature to eliminate or decrease chemical segregation by diffusion.
保持高温以消除或减少扩散引起的化学偏析。
Screw conveyor 螺旋输送机 (auger, spiral conveyor, worm conveyor) A machine for bulk handling of semi-solid materials, consisting of a helical screw which rotates in a trough or casing.
(螺旋输送机、螺旋输送机、蜗杆输送机)一种用于散装搬运半固态材料的机器,由在槽或外壳中旋转的螺旋螺杆组成。
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。
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。
Preload relaxation 预载松弛 Local yielding, due to excess bearing stress under nuts and bolt heads (caused by high local spots, rough surface finish, and lack of perfect squareness of bolt and nut bearing surfaces), may result in preload relaxation after preloads are first applied to a bolt.
由于螺母和螺栓头下的轴承应力过大(由局部斑点高、表面粗糙以及螺栓和螺母轴承表面缺乏完美的方正度造成),局部屈服可能会在首次向螺栓施加预载荷后导致预载荷松弛。
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。
Valve spring 气门弹簧 The spring that restores a valve to its closed position after having been opened, and is also intended to prevent valve bounce.
在阀门打开后将其恢复到关闭位置的弹簧,也用于防止阀门反弹。
Adhesive strength 粘合强度 The strength of an adhesively bonded joint, usually measured in tension (perpendicular to the plane of the bonded joint) or in shear
粘合接头的强度,通常以拉伸(垂直于粘合接头的平面)或剪切测量
Surface hardness 表面硬度 (superficial hardness) Indentation hardness on, and for some distance below, the surface of a component, as opposed to its bulk hardness. Depending on the resolution required, micro- or nano-hardness testing machines are employed.
(表面硬度)与整体硬度相反,部件表面及其下方一定距离的压痕硬度。根据所需的分辨率,可使用微型或纳米硬度测试机。
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。
Fracture test 断裂试验 A test in which a specimen is broken and its fracture surface is examined with the unaided eye or with a low-power microscope to determine such factors as composition, grain size, case depth, or internal discontinuities. 1. The recording of load-deflexion (or stress–strain) in a specimen loaded monotonically until it breaks in tension, compression, shear, or torsion. 2. In fatigue, determination of the number of cycles to fracture for a specimen under different patterns of repeated loading. 3. Experiments to determine fracture toughness.
一种试验,其中试样被破坏并用肉眼或低倍显微镜检查其断裂表面,以确定成分、晶粒尺寸、表层深度或内部不连续性等因素。1.记录单调加载试样的载荷偏转(或应力-应变),直到其在拉伸、压缩、剪切或扭转中断裂。2.在疲劳技术中,确定试样在不同重复载荷模式下的断裂循环次数。3.测定断裂韧性的实验。
Deflection temperature under load (DTUL) 负载变形温度(DTUL) The temperature at which a simple cantilever beam deflects a given amount under load. Formerly called heat distortion temperature.
简单悬臂梁在负载下偏转给定量的温度。以前称为热变形温度。
Humidify 加湿 To add water vapour to air or another gas to increase its humidity.
将水蒸气添加到空气或其他气体中以增加其湿度。
Band clutch 带式离合器 A friction clutch in which drive is achieved by a band contracting on to the rim of the clutch.
一种摩擦离合器,其驱动是通过一条带在离合器边缘上收缩来实现的。
Grinding 研磨 1. A process of high-speed multiple scratching of surfaces by a wheel formed from hard grits and a binder which are progressively exposed as the binder wears away. It is a process of micromachining employed particularly in accurate finishing operations on hard materials. 2. A form of comminution.
1.一种通过由硬砂砾和粘合剂形成的轮对表面进行高速多次刮擦的方法,所述硬砂砾和粘结剂随着粘合剂的磨损而逐渐暴露。这是一种微机械加工工艺,特别适用于硬材料的精确精加工操作。2.一种粉碎形式。
Vibrometer 测振仪 A device used to measure the motion of a vibrating surface, typically using a contactless laser-based technique.
一种用于测量振动表面运动的装置,通常使用非接触激光技术。
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。
Rotary valve (rotating valve) 旋转阀 A cylindrical or conical plug in which there is a transverse hole through which fluid can flow when the hole is aligned with the adjacent piping.
一种圆柱形或锥形塞,其中有一个横向孔,当该孔与相邻管道对齐时,流体可通过该孔流动。
Normal stress (Unit N) 法向应力(单位:N) The stress component perpendicular to a plane on which forces act. Normal stress may be either tensile stress or compressive stress. A stress in a fluid (such as pressure) or a solid, that is perpendicular to the surface on which it acts. The surface may be a real external surface or an imaginary internal one.
垂直于受力平面的应力分量。法向应力可以是拉应力或压应力。流体(如压力)或固体中垂直于其作用表面的应力。该表面可以是真实的外表面或假想的内表面。
Testing machine (load-measuring type) 试验机(负载测量型) A mechanical device for applying a load (force) to a specimen.
向试样施加载荷(力)的机械装置。
Maximum-and-minimum thermometer 最高和最低温度计 (minimum-maximum thermometer, Six’s thermometer) A liquid-in-glass instrument designed to register the maximum and minimum temperatures experienced over a given time period.
(最低-最高温度计,Six's温度计)一种液体玻璃仪器,用于记录给定时间段内经历的最高和最低温度。
Steady pin 定位销 A dowel, key, or pin that prevents a pulley from turning on its shaft.
防止滑轮在其轴上转动的销钉、键或销。
Dew point analyzer 露点分析仪 An atmosphere monitoring device that measures the partial pressure of water vapor in an atmosphere.
一种大气监测装置,用于测量大气中水蒸气的分压。
Strain energy 应变能 A measure of the energy absorption characteristics of a material determined by measuring the area under the stress-strain diagram.
通过测量应力-应变图下的面积确定的材料能量吸收特性的度量。
Acoustic droplet ejection 声液滴喷射 The ejection of small droplets from the surface of a liquid that results from focusing high-intensity ultrasound near the surface.
由于在表面附近聚焦高强度超声波而从液体表面喷射出小液滴。
Gear motor 齿轮马达 Essentially a gear pump run in reverse, in which high-pressure fluid supplied to one side of the casing causes the gears to rotate.
本质上是一个齿轮泵反向运行,其中供应到外壳一侧的高压流体导致齿轮旋转。
Grip length 夹紧长度 Combined thickness of all the things clamped together by the bolt and nut, including washers, gaskets, and joint members.
由螺栓和螺母夹紧在一起的所有部件的总厚度,包括垫圈、垫圈和接头构件。
Impact extrusion 冲击挤压 The extrusion of separate components of soft metals whose properties permit the action to be performed quickly.
挤压单独的软金属组件,其特性允许快速执行操作。
Stress amplitude 应力幅值 One-half the algebraic difference between the maximum and minimum stress in one cycle of a repetitively varying stress.
重复变化应力的一个循环中最大和最小应力之间代数差的一半。
Centre line 中心线 1. In an engineering drawing, a line of symmetry. 2. An imaginary line along a pipe, duct, or shaft that defines an axis of symmetry. 3. An imaginary straight line parallel to the intended direction of a surface located such that the areas above and below the line and the real wavy (rough) surface cancel out.
1.在工程图中,对称线。2.沿着管道、管道或竖井定义对称轴的假想线。3.一条平行于表面预期方向的假想直线,该直线上方和下方的区域与真实的波状(粗糙)表面相抵消。
Toggle (toggle clamp) 拨动(拨动夹) A device consisting of two pinned levers that are almost in line between two end points in the same plane. Bringing the levers into line generates large forces between the ends. Used to obtain a large mechanical advantage or as a locking mechanism.
由两个销杆组成的装置,在同一平面的两个端点之间几乎成一条直线。将杠杆对齐会在端部之间产生较大的力。用于获得较大的机械优势或用作锁定机构。
Ductile 延展性材料 (ductile material) Describes a material that can be deformed permanently to large strains without fracture. If a bolt can be stretched well past its yield point before breaking, it is said to be ductile.
(延展性材料)描述一种可以永久变形到大应变而不断裂的材料。如果螺栓在断裂前可以很好地拉伸超过其屈服点,则称其具有延展性。
Transducer 传感器 A device which converts one form of energy into another. An ultrasonic transducer, for example, converts electrical energy into acoustic energy (at ultrasonic frequencies) and vice versa.
将一种形式的能量转换为另一种形式能量的装置。例如,超声换能器将电能转换为声能(在超声频率下),反之亦然。
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。
Absolute pressure 绝对压力 1. The pressure measured relative to zero pressure (vacuum). 2. Gage pressure plus barometric pressure in the same units.
1.相对于零压力(真空)测量的压力。2.表压加上大气压力的单位相同。
Forging 锻造处理 The process of forming raw steel into specified shapes. Some examples of forged products would be hex bolts, clevises, and barrier pins. 1. A method of component manufacture by hammering metal by hand or by machine (drop forge, press). 2. A part made by the process of forging.
将生钢制成特定形状的过程。锻造产品的一些例子是六角螺栓、U形夹和障碍销。 1. 一种通过手工或机器锤击金属(落锻、压力机)制造部件的方法。2.通过锻造工艺制成的零件。
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。
Minimum stress (Smin) 最小应力(Smin) In fatigue, the stress having the lowest algebraic value in the cycle, tensile stress being considered positive and compressive stress negative.
在疲劳中,循环中代数值最低的应力,拉应力被视为正应力,压应力为负应力。
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。
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。
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。
Working stress (Unit Pa) 工作应力(单位Pa) The stress under which a component or structure is designed to operate under normal conditions.
部件或结构设计为在正常条件下运行的应力。
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。
Bearing failure 轴承故障 A failure that occurs in a riveted or bolted joint when the transverse load divided by the bearing area results in a stress that leads to permanent plastic deformation.
当横向载荷除以承载面积产生导致永久塑性变形的应力时,铆接或螺栓连接中发生的失效。
Altitude 高度 (Unit m) Vertical height measured relative to a specified datum such as sea level.
(单位m)相对于特定基准(例如海平面)测量的垂直高度。
Fastener quality 紧固件质量 A fastener’s adherence to its specification for dimensional tolerances, mechanical properties, and other requirements stated under applicable standards.
紧固件对尺寸公差、机械性能和适用标准规定的其他要求的规范的遵守情况。
Total elongation 总伸长率 A total amount of permanent extension of a test piece broken in a tensile test.
拉伸试验中断裂试样的永久延伸总量。
Shear 扭剪 The type of force that causes or tends to cause two contiguous parts of the same body to slide relative to each other in a direction parallel to their plane of contact.
导致或倾向于导致同一物体的两个相邻部分在平行于其接触面的方向上相对滑动的力的类型。
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。
Complete decarburization 完全脱碳 Decarburization with sufficient carbon loss to show only clearly defined ferrite grains under metallographic examination.
脱碳,具有足够的碳损失,以在金相检查下仅显示清晰定义的铁素体晶粒。
Strength of bolt 螺栓强度 An ambiguous term which can mean Ultimate strength or Proof load or Endurance limit or Yield strength.
一个模棱两可的术语,可表示极限强度或验证荷载或耐久极限或屈服强度。
Actual value 实际价值 The output of a plant that is being controlled, i.e. the controlled variable. Not directly accessible by the control system, as it can only be measured by a sensor which may distort the measurement.
受控设备的输出,即受控变量。控制系统不能直接访问,因为它只能由可能会扭曲测量结果的传感器测量。
Selective heating 局部加热 Intentionally heating only certain portions of a workpiece.
有意仅加热工件的某些部分。
Regenerative pump 涡流泵  (regenerative turbine pump, peripheral pump) A pump with a double-sided impeller having a large number of radial blades. The pressure of the pumped liquid increases progressively over several revolutions of the impeller. It is  particularly suited to producing large heads at small flow rates without cavitation.
(再生涡轮泵,外围泵)具有具有大量径向叶片的双面叶轮的泵。泵送液体的压力在叶轮的几圈内逐渐增加。它特别适合于在小流速下产生大水头且不产生气穴。
Standardization 标准化 1. National and international agreements for design, manufacture, materials, performance, practices, requirements, strength, etc. which ensure common results wherever an item is made and wherever used. 2. The manufacture of components so that interchangeability of parts during assembly of new, or repair of old, items is possible without ‘fitting’.
1.关于设计、制造、材料、性能、惯例、要求、强度等的国家和国际协议,确保在任何地方制造和使用物品都能产生共同结果。2.部件的制造,以便在装配新部件或维修旧部件时,无需“装配”即可实现部件的互换性。
Centrifugal compressor 离心式压缩机 A compressor in which kinetic energy is added to a fluid by radial acceleration in an impeller and then converted into a pressure increase by flow though a diffuser.
一种压缩机,其中动能通过叶轮中的径向加速度添加到流体中,然后通过扩散器的流动转换为压力增加。
Relaxation rate 松弛率 The absolute value of the slope of a stress-relaxation curve at a given time.
给定时间应力松弛曲线斜率的绝对值。
Thermal reactor 热反应器 An enlarged exhaust manifold bolted directly to the cylinder head of a piston engine, in which the oxidation of carbon monoxide and unburned hydrocarbons in the exhaust gas is enhanced.
一种扩大的排气歧管,直接用螺栓固定在活塞式发动机的气缸盖上,其中一氧化碳和未燃烧碳氢化合物的氧化作用增强。
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。
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。
Mechanical alloying 机械合金化 Production of alloys from powders by consolidation, e.g. hotpressing or extrusion, followed by hot and/or cold working and final annealing. Materials such as dispersion-strengthened alloys, high-temperature aluminium alloys, and amorphous alloys can be made in this way.
通过固结(例如热压或挤压)从粉末生产合金,然后进行热和/或冷加工和最终退火。用这种方法可以制造弥散强化合金、高温铝合金和非晶合金等材料。
Turboblower 涡轮鼓风机 A centrifugal or axial compressor or fan.
离心式或轴流式压缩机或风扇。
Bypass valve 旁通阀 A valve that directs flow through a bypass.
引导流过旁路的阀门。
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。
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。
Erosion 侵蚀 Progressive loss of original material from a solid surface due to mechanical interaction between that surface and a fluid, a multicomponent fluid, or impinging liquid or solid particles.
由于固体表面与流体、多组分流体或撞击液体或固体颗粒之间的机械相互作用,原始材料从固体表面逐渐损失。
Heat (q, Q) (Unit J) 热量(q, Q)(单位J) A form of energy that is transferred across the boundary of a system at one temperature to another system (or the surroundings) at a different temperature by virtue of the temperature difference between them. Heat can be identified only as it crosses the boundary. A body can never be said to contain heat which is thus a transient phenomenon.
一种能量形式,由于它们之间的温差在一个温度下通过系统边界传递到另一个温度不同的系统(或环境)。只有当热量穿过边界时才能识别。一个物体不能说永远含有热量,这是一种瞬态现象。
Crack length (depth) (a) 裂纹长度(深度)(a) In fatigue and stress corrosion cracking, the physical crack size used to determine the crack growth rate and the stress-intensity factor. For the compact-type specimen, crack length is measured from the line connecting the bearing points of load application. For the center-cracked-tension specimen, crack length is measured from the perpendicular bisector of the central crack.
在疲劳和应力腐蚀裂纹中,用于确定裂纹扩展速率和应力强度因子的物理裂纹尺寸。对于紧凑型试样,裂纹长度从连接载荷施加点的线开始测量。对于中心裂纹拉伸试样,从中心裂纹的垂直平分线测量裂纹长度。
Taper pins 圆锥销 A pin or peg of circular cross section that tapers along its length. Steel pins used for locating and holding the machine parts in position on a shaft.
沿其长度逐渐变细的圆形横截面的销钉或销钉。用于在轴上定位和固定机器零件的钢销。
Available head (Unit m) 可用水头(单位米) In a hydroelectric power system, the difference between the vertical height of the water level in the supply reservoir above the turbine inlet less the head loss due to friction and fittings in the duct leading to the turbine.
在水力发电系统中,水轮机入口上方供水水库中水位垂直高度之间的差减去由于通向涡轮机的管道中的摩擦和配件造成的水头损失。
Mechanical vibration 机械振动 The motion of a particle or body which oscillates about a position of equilibrium.
围绕平衡位置摆动的粒子或物体的运动。
Second (s) 秒(s) The SI base unit of time equal to 9 192 631 770 times the period of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom.
SI基时间单位等于9192631770倍的辐射周期,对应于铯-133原子基态的两个超精细能级之间的跃迁。
Generator 发电机 1. A machine for converting mechanical energy to electrical energy. 2. (generatrix) A point, line, or surface regarded as moving and so forming a line, a surface, or a volume, respectively.
1.将机械能转化为电能的机器。2.(母线)被认为是运动的点、线或面,因此分别形成一条线、一个面或一个体积。
Spring materials 弹簧材料 Mainly metals including plain-carbon and corrosion-resisting steels, phosphor bronze, spring brass, beryllium copper and nickel alloys, all of which in their workhardened states permit large reversible elastic strains without permanent deformation.
主要是金属,包括普通碳钢和耐腐蚀钢、磷青铜、弹簧黄铜、铍铜和镍合金,所有这些金属在其加工硬化状态下都允许大的可逆弹性应变而不会产生永久变形。
Quench hardening 淬火硬化 (1) Hardening suitable alpha-beta alloys (most often certain copper to titanium alloys) by solution treating and quenching to develop a martensitic-like structure. (2) In ferrous alloys, hardening by austenitizing and then cooling at a rate such that a substantial amount of austenite transforms to martensite.
(1)通过固溶处理和淬火硬化合适的α-β合金(通常是某些铜-钛合金),以形成类似马氏体的结构。(2)在铁合金中,通过奥氏体化硬化,然后以一定速度冷却,使大量奥氏体转变为马氏体。
Threading machine 螺纹机 A machine used to cut an external thread on a rod, tube, bolt blank, etc. or an internal thread in a hole, tube, nut blank, etc.
用于切割杆、管、螺栓毛坯等上的外螺纹或孔、管、螺母毛坯等中的内螺纹的机器。
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。
Compression crease 压缩折痕 A crease formed during the compression of composites having a high volume fraction of filaments. These composites fail in compression by forming a crease at an angle to the loading axis.
在压缩具有高体积分数长丝的复合材料期间形成的折痕。这些复合材料通过形成与加载轴成一定角度的折痕而在压缩中失效。
Relaxation 松弛 The loss of tension, and therefore Clamping force, in a bolt and joint as a result of Embedment, vibration loosening, gasket creep, differential thermal expansion, etc.
由于嵌入、振动松动、垫圈蠕变、热膨胀差等原因,螺栓和接头中的张力损失,因此夹紧力损失。
True strain 真应变  (1) The ratio of the change in dimension, resulting from a given load increment, to the magnitude of the dimension immediately prior to applying the load increment. (2) In a body subjected to axial force, the natural logarithm of the ratio of the gage length at the moment of observation to the original gage length. Also known as natural strain. Compare with engineering strain.
(1)给定载荷增量导致的尺寸变化与施加载荷增量之前尺寸大小的比率。(2)在承受轴向力的物体中,观察时刻标距与原始标距之比的自然对数。也称为自然应变。与工程应变相比。
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。
Radial marks 径向标记 Lines on a fracture surface that radiate from the fracture origin and are visible to the unaided eye or at low magnification. Radial lines result from the intersection and connection of brittle fractures propagating at different levels. Also known as shear ledges.
断裂表面上的线,从断裂起点辐射,肉眼可见或在低放大率下可见。径向线是在不同层面上传播的脆性断裂相交和连接的结果。也称为剪切壁架。
Nanoparticles 纳米颗粒 Particles with dimensions of order 1 nm which have either been introduced into microstructures for reinforcement or are present as impurities.
尺寸为1nm级的颗粒,其已被引入微结构中用于增强或作为杂质存在。
Available draught (Unit Pa) 可用通风量(单位Pa) The reduced pressure of combustion gases in a furnace or boiler, either forced or due to the buoyancy of hot gases, which is used to draw in combustion air and remove products of combustion.
炉子或锅炉中燃烧气体的压力降低,无论是强制还是由于热气体的浮力,用于吸入燃烧空气并去除燃烧产物。
Blind rivet 盲孔铆钉 A rivet that enables a connexion to be made from one side only of an assembly.
一种铆钉,可以仅从组件的一侧进行连接。
Plane-strain fracture toughness (KIc) 平面应变断裂韧性(KIc) The crack extension resistance under conditions of crack-tip plane strain.
裂纹尖端平面应变条件下的裂纹扩展阻力。
Flame straightening 火焰矫直 Correcting distortion in metal structures by localized heating with a gas flame.
通过使用气体火焰进行局部加热来纠正金属结构的变形。
Fibreglass 玻璃纤维 Fibreglass is used in studs and nuts for applications when the fastener should be non-corrosive, low in conductivity, or transparent to electromagnetic waves.
当紧固件应无腐蚀性、低导电性或对电磁波透明时,玻璃纤维用于螺柱和螺母中。
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。
Compressor bleed 压缩机排气 The removal of air before the final stage of a multistage compressor operating below design speed, to prevent the final stage from choking.
在低于设计速度运行的多级压缩机的末级之前去除空气,以防止末级阻塞。
Physical properties 物理性质 Properties of a material the determination of which does not involve the deformation or destruction of the specimen—for example, density, electrical conductivity, coefficient of thermal expansion, magnetic permeability, and lattice parameter. Does not include chemical reactivity or the properties more appropriately regarded as mechanical properties.
不涉及试样变形或破坏的材料特性,例如密度、电导率、热膨胀系数、磁导率和晶格参数。不包括化学反应性或更适当地视为机械的性质。
Single-shear test 单剪试验  (1) A shear test similar to the double-shear test used for round-bar specimens, but that uses only one stationary shear blade. (2) A shear test that uses a sheet or thin-plate specimen.
(1)一种剪切试验,类似于用于圆棒试样的双剪切试验,但仅使用一个固定剪切刀片。(2)使用薄板或薄板试样的剪切试验。
Critical diameter 临界直径 (D) Diameter of the bar that can be fully hardened with 50% martensite at its center.
(D)中心有50%马氏体可完全硬化的棒材直径。
Mechanical properties of solid materials 固体材料的力学性能 The strength and stiffness properties of solid materials such as fracture toughness, the moduli of elasticity, percent elongation,
固体材料的强度和刚度特性,例如断裂韧性、弹性模量、伸长率、
Distortion 扭曲 Any deviation from an original size, shape, or contour that occurs because of the application of stress or the release of residual stress.
由于施加应力或释放残余应力而发生的与原始尺寸、形状或轮廓的任何偏差。
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。
Corrosive wear 腐蚀磨损 Wear in which chemical or electrochemical reaction with the environment is significant.
与环境发生显着化学或电化学反应的磨损。
Thread form 螺纹形式 The cross-sectional shape of the threads, defining thread angle, root, and crest profiles, etc. Thread length Length of that portion of the fastener which contains threads cut or rolled to full depth.
螺纹的横截面形状,定义螺纹角度、齿根和齿冠轮廓等。螺纹长度:紧固件中包含全深度切割或轧制螺纹的部分的长度。
Continuous-type furnace 连续式炉 A furnace used for heat treating materials that progress continuously through the furnace, entering one door and being discharged from another. See belt furnac, direct-fired tunnel-type furnac, rotary retort furnace, shaker-hearth furnace.
一种用于热处理材料的炉子,该炉子连续通过炉子,进入一个门并从另一个门排出。参见带式高炉、直燃隧道式高炉、旋转罐式炉、振动炉。
Minute (min) 分钟(min) A non-SI unit of time. The conversion to SI is 1 min = 60 s.
非SI时间单位。转换为1分钟=60秒。
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。
Turbulent flow (turbulence) 湍流 Fluid motion characterized by disorderly, rotational (i.e. vortical) three-dimensional velocity fluctuations covering a wide range of frequency and length scales. The pressure, temperature, and other fluid properties also fluctuate and the diffusion of heat, mass, and momentum is greatly enhanced. As are laminar and transitional flow, turbulent flow of a Newtonian fluid is governed by the Navier–Stokes equations which can in principle be solved by direct numerical simulation (DNS) in which all time and length scales of the fluctuating motion are resolved.
流体运动的特点是无序、旋转(即旋涡)三维速度波动,覆盖广泛的频率和长度尺度。压力、温度和其他流体特性也会波动,热、质量和动量的扩散会大大增强。与层流和过渡流一样,牛顿流体的湍流由Navier-Stokes方程控制,该方程原则上可以通过直接数值模拟(DNS)求解,在直接数值模拟中,波动运动的所有时间和长度尺度都可以求解。
Total heat (Unit kJ) 总热量(单位kJ) An alternative term for enthalpy. It is inappropriate as it suggests that it includes kinetic energy in the same way as total enthalpy, but it does not. Also, heat and enthalpy are quite different quantities, as their definitions show.
焓的另一个术语。这是不恰当的,因为它表明,它包括动能的方式与总焓相同,但它实际上并不是的。此外,热和焓是完全不同的量,正如它们的定义所示。
Sound pressure (Unit μPa) 声压(单位:μPa) The instantaneous deviation of pressure from the ambient pressure caused by the passage of a sound wave, which can be measured by a microphone in air and a hydrophone in water.
声波传播引起的压力与环境压力的瞬时偏差,可通过空气中的麦克风和水中的水听器测量。
Brittle lacquer coating 脆性漆涂层 A lacquer that, when painted on to an unloaded body, reveals the direction of maximum tension stresses from the pattern of cracking produced in the lacquer when the body is loaded.
一种漆,当涂在未加载的车身上时,从车身加载时在漆中产生的裂纹图案中显示出最大拉应力的方向。
Critical temperature 临界温度 (1) Synonymous with critical point if the pressure is constant. (2) The temperature above which the vapor phase cannot be condensed to liquid by an increase in pressure.
(1) 如果压力恒定,则与临界点同义。(2) 高于该温度时,气相不能通过压力升高而冷凝为液体。
Ion nitriding 离子氮化 A method of surface hardening in which nitrogen ions are diffused into a workpiece in a vacuum through the use of high-voltage electrical energy. Synonymous with plasma nitriding or glowdischarge nitriding.
一种表面硬化方法,其中氮离子通过使用高压电能在真空中扩散到工件中。与等离子体氮化或辉光放电氮化同义。
DTI DTI Direct tension indicator. A fastener used primarily in the structural steel industry, designed to indicate that a certain minimum amount of tension has been developed in the fastener during assembly.
直接张力指示器。一种主要用于结构钢行业的紧固件,旨在表明在装配过程中紧固件中产生了一定的最小张力。
Workspace (Unit m³) 工作空间(单位m³) (working-space volume) The volume around the base frame of a robot, defined by the reach of the robot. The robot can thus only perform tasks within this volume.
(工作空间体积)机器人基架周围的体积,由机器人的可达范围定义。因此,机器人只能执行该体积内的任务。
Fatigue wear 疲劳磨损 Wear of a solid surface caused by fracture arising from material fatigue.
由材料疲劳引起的断裂引起的固体表面磨损。
Thermal electromotive force 热电动势 The electromotive force generated in a circuit containing two dissimilar metals when one junction is at a temperature different from that of the other.
当一个结处于不同于另一个结的温度时,在含有两种不同金属的电路中产生的电动势。
Strain rate 应变率 The time rate of straining for the usual tensile test. Strain as measured directly on the specimen gage length is used for determining strain rate. Because strain is dimensionless, the units of strain rate are reciprocal time.
通常拉伸试验的应变时间速率。直接在试样标距上测量的应变用于确定应变率。因为应变是无因次的,所以应变率的单位是倒数时间。
Rotor 转子 A part of a machine that rotates on a shaft (rotor shaft) about its own axis, such as the blade-carrying discs of a turbine, the blades of a helicopter, or the rotating parts of a Roots blower.
绕轴(转子轴)绕其自身轴线旋转的机器部件,如涡轮叶片、直升机叶片或罗茨鼓风机的旋转部件。
Crank pin 曲柄销 It is a short shaft parallel to the axis of the crankshaft but radially offset from it, to which is attached the big end of a connecting rod in a bearing. Sometimes the crank pin is supported at one end only (a wrist pin) but in built-up or one-piece forged crankshafts, the crank pin is supported by thick plates (crank arms, crank webs) at either end.
它是一个短轴,平行于曲轴的轴线,但径向偏移,轴承中连杆的大端连接到该短轴上。有时曲柄销仅在一端支撑(腕销),在组合式或整体锻造曲轴中,曲柄销在两端由厚板(曲柄臂、曲柄腹板)支撑。
Air-cooled engine 风冷发动机 An internal-combustion engine directly cooled by airflow, rather than by water flowing through the engine block being cooled by a radiator.
一种由气流直接冷却的内燃机,而不是通过流经发动机缸体的水被散热器冷却。
Torsion test 扭力测试 A test designed to provide data for the calculation of the shear modulus, modulus of rupture in torsion, and yield strength in shear.
为计算剪切模量、扭转断裂模量和剪切屈服强度而设计的试验。
Rotary blower 旋转鼓风机 (rotary compressor) A positive-displacement gas compressor which may be of the blade type, helical-screw type, meshing-lobe type (the Roots blower), or sliding-vane type.
(旋转式压缩机)一种容积式气体压缩机,可以是叶片式、螺旋式、啮合凸角式(罗茨鼓风机)或滑动叶片式。
Coherent precipitate 相干沉淀 A crystalline precipitate that forms from solid solution with an orientation that maintains continuity between the crystal lattice of the precipitate and the lattice of the matrix, usually accompanied by some strain in both lattices. Because the lattices fit at the interface between precipitate and matrix, there is no discernible phase boundary.
由固溶体形成的结晶沉淀物,其取向保持沉淀物晶格和基体晶格之间的连续性,通常伴随着两个晶格中的一些应变。由于晶格适合于沉淀和基体之间的界面,因此不存在可识别的相边界。
International System of Units 国际单位制 (SI system of units, Le Système international d’unités) The standard system of units now used almost universally in science and engineering except in the United States. The definitive reference on the SI is a booklet published by the International Bureau of Weights and Measures, often referred to as the BIPM SI Brochure. There are seven base units: metre (symbol m) for length; kilogram (kg) for mass; mole (mol) for amount of substance; second (s) for time; kelvin (K) for temperature; ampere (A) for electric current; and candela (cd) for luminous intensity. New SI unit definitions, based upon the values of the universal constants of nature (also termed the fundamental physical constants: the Avogadro constant, the Boltzmann constant, and the Planck constant), came into effect on 20 May 2019. Minor adjustments were also made to the values of these constants. In addition to the base units, there are 22 coherent derived units, including radian (rad) for plane angle, steradian (sr) for solid angle, hertz (Hz) for frequency, newton (N) for force, pascal (Pa) for pressure, joule (J) for energy, work, and amount of heat, and watt (W) for power and radiant flux.  Recommended practice is to avoid combinations such as N/mm², MN/m² being preferred.(kg) for mass; mole (mol) for amount of substance; second (s) for time; kelvin (K) for temperature; ampere (A) for electric current; and candela (cd) for luminous intensity. New SI unit definitions, based upon the values of the universal constants of nature (also termed the fundamental physical constants: the Avogadro constant, the Boltzmann constant, and the Planck constant), came into effect on 20 May 2019. Minor adjustments were also made to the values of these constants. In addition to the base units, there are 22 coherent derived units, including radian (rad) for plane angle, steradian (sr) for solid angle, hertz (Hz) for frequency, newton (N) for force, pascal (Pa) for pressure, joule (J) for energy, work, and amount of heat, and watt (W) for power and radiant flux.  Recommended practice is to avoid combinations such as N/mm², MN/m² being preferred.
(国际单位制,Le Système international d\\\'unités)目前美国除外,在科学和工程中几乎是普遍使用的标准单位制。SI的最终参考是国际度量衡局出版的小册子,通常称为BIPM SI小册子。有七个基本单位:米(符号m)表示长度;质量为千克(kg);物质量的摩尔(mol);时间为秒;开尔文(K)表示温度;电流为安培(A);而坎德拉(cd)表示发光强度。新的国际单位制定义于2019年5月20日生效,该定义基于自然界的普遍常数(也称为基本物理常数:阿伏伽德罗常数、玻尔兹曼常数和普朗克常数)。这些常数的值也进行了少量调整。除了基本单位外,还有22个相干导出单位,包括平面角的弧度(rad)、立体角的斯特拉迪安(sr)、频率的赫兹(Hz)、力的牛顿(N)、压力的帕斯卡(Pa)、能量、功和热量的焦耳(J)以及功率和辐射通量的瓦特(W)。建议的做法是避免N/mm²、MN/m²等组合。
Pressure ratio 压力比 One pressure divided by another which may be a reference pressure. In many flow and thermodynamic processes, the pressure ratio is more important than the absolute pressure levels. For example, in compressible gas flow the Mach number is determined by the ratio of the stagnation pressure to the static pressure.
一个压力除以另一个压力,该压力可以是参考压力。在许多流动和热力学过程中,压力比比绝对压力水平更重要。例如,在可压缩气流中,马赫数由停滞压力与静压之比决定。
Starting torque (Unit N.m) 起动扭矩(单位:N.m) The torque developed by a motor at zero rotational speed in order to initiate rotation of the applied load.
电机在零转速下产生的扭矩,以启动所施加负载的旋转。
Combustible 易燃 (inflammable) A term for substances that can be ignited and burned.
(易燃)可点燃和燃烧的物质的术语。
Galvanic protection 电流保护 The coating on a fastener is said to provide galvanic protection if it is more anodic than the fastener and will, therefore, be destroyed instead of the fastener. Zinc plate (galvanizing) provides galvanic protection to steel fasteners, for example.
如果紧固件上的涂层比紧固件更具阳极性,则据说它可以提供电流保护,将会因此被破坏而不是紧固。例如,锌板(镀锌)为钢紧固件提供电流保护。
Maximum material condition 最大材料条件 (maximum metal condition) The situation where the volume of a manufactured component corresponds to the upper limit for all toleranced external dimensions, and to the lower limit for all internal dimensions.
(最大金属条件)制造部件的体积对应于所有公差外部尺寸的上限和所有内部尺寸的下限的情况。
Cleavage 分裂 The tendency of a material to cleave or split along definite crystallographic planes.
材料沿特定晶面劈裂或分裂的趋势。
Terminal temperature difference (Unit K) 终端温差(单位K) The temperature difference between the two fluid streams at either inlet or outlet of a heat exchanger.
热交换器入口或出口处两种流体流之间的温差。
Dimensioning 尺寸标注 The specification on an engineering drawing of the size (e.g. length, radius, angle, or spacing) and the relative location (e.g. angular position) of each feature of a component. The numerical values often include the tolerances. There should be no more dimensions than are necessary to manufacture the component.
工程图纸上对部件每个特征的尺寸(例如长度、半径、角度或间距)和相对位置(例如角位置)的规范。数值通常包括公差。尺寸不应超过制造组件所需的尺寸。
Guided-bend test 导向弯曲试验 A test in which the specimen is bent to a definite shape by means of a punch (mandrel) and a bottom block.
用冲头(心轴)和底块将试样弯曲成一定形状的试验。
Nut box mechanism 螺母箱机械装置 In a lathe it is used to engage and disengage the lead screw for thread cutting. This comprises a pair of half-nuts capable of sliding in vertical slides in or out of mesh with the lead screw.
在车床中,它用于接合和分离丝杠以进行螺纹切削。这包括一对半螺母,能够在与丝杠啮合的垂直滑动中滑动。
Circular pitch 齿距 The distance from the center of one gear tooth to the center of the next gear tooth measured on the pitch line.
在节线上测量的从一个轮齿中心到下一个轮齿中心的距离。
Maximum load (Pmax) 最大负载(Pmax) (1) The load having the highest algebraic value in the load cycle. Tensile loads are considered positive and compressive loads negative. (2)Used to determine the strength of a structural member; the load that can be borne before failure is apparent.
(1)负载循环中具有最高代数值的负载。拉伸荷载视为正荷载,压缩荷载视为负荷载。(2)用于确定结构构件的强度;失效前可承受的载荷是明显的。
Shoulder screw 轴肩螺钉 A screw having two or more diameters or shoulders and commonly used for supporting levers and other machine parts that have to operate freely.
一种具有两个或两个以上直径或轴肩的螺钉,通常用于支撑杠杆和其他必须自由操作的机器部件。
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。
Die casting 压铸 A process in which molten metal, particularly alloys of aluminium, magnesium, copper, and zinc, is forced under pressure (10 to 200 MPa) into a reusable hardened-steel mould machined into a die.
在压力(10至200MPa)下将熔融金属(特别是铝、镁、铜和锌的合金)强制进入加工成模具的可重复使用的硬化钢模具中的过程。
Brake fluid 制动液 The hydraulic fluid used to transmit force to the pistons in disc brakes or the wheel cylinders in drum brakes. Requirements include a high boiling point and low hygroscopy.
用于将力传递到盘式制动器中的活塞或鼓式制动器中的轮缸的液压油。要求包括高沸点和低吸湿性。
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。
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。
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。
Diffusion coating 扩散涂层 Coating on metal for corrosion- and/or oxidation-resistance. Coatings are produced by heating a metal in contact with an alloy in powder, liquid, or gaseous form at elevated temperature such that atoms of the coating diffuse into the substrate. Examples include chromium, aluminium, or silicon on substrates such as nickel-based superalloys, steels, and refractory metals.
金属上的防腐和/或抗氧化涂层。涂层是通过在高温下加热与粉末、液体或气体形式的合金接触的金属,从而使涂层的原子扩散到基体中而产生的。实例包括基底上的铬、铝或硅,如镍基高温合金、钢和耐火金属。
Stress-intensity calibration 应力强度校准 A mathematical expression, based on empirical or analytical results, that relates the stress-intensity factor to load and crack length for a specific specimen planar geometry. Also known as Kcalibration.
基于经验或分析结果的数学表达式,该表达式将特定试样平面几何形状的应力强度因子与载荷和裂纹长度联系起来。也称为K校准。
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