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机械工程英语第二版 part2 第11单元翻译

机械工程英语第二版 part2 第11单元翻译
机械工程英语第二版 part2 第11单元翻译

Unit11 Rapid Prototyping and Manufacturing Technologies 快速成型与制造技术Introduction 导言

Manufacturing community is facing two important challenging tasks: Substantial reducition of product development time; and Improvement on flexibility for manufacturing multi-variety and small batch-size products. Computer-aided design and manufacturing(CAD and CAM) have significantly improved the traditional production design and manufacturing. However, there are a number of obstacles in true integration of computer-aided design with computer-aided manufacturing for rapid development of new prodcts.

制造社会面临两个重要的富有挑战性的任务:大幅度减少产品开发时间,提高多种产品,小批量大小产品的制造灵活性。计算机辅助设计与制造(CAD 和CAM)有着显著改善了传统的产品设计及制造。然而,在新产品快速开发方面有一些障碍,这些障碍阻碍着计算机辅助设计与计算机辅助制造的真正集成。

To substantially shorten the time for developing patterns, moulds, and prototypes, some manufacturing enterprise have started to use rapid prototyping(RP) methods for complex partterns making and component prototyping. Over the past few years, a variety of new rapid manufacturing technologies, generally called Rapid Prototyping and Manufacturing(RP & M) have emerged; the technologies developed include stereo lithography(SL),selective laser sintering(SLS), fused deposition modeling(FDM), laminated object manufacturing(LOM), and three dimensional printing(3D Printing). These technologies are capable of directly generating physical objects from CAD databases. They have a common important feature: the prototype part is produced by adding materials rather than removing materials, that is , a part is first modeled by a geometric modeler such as a solid modeler, and then is mathematically sectioned(sliced) into a series of parallel cross-section pieces. For each piece, the curing or binding paths are generated. These curing or binding paths are directly used to instruct the machine for producing the part by solidifying or binding a line of material. After a layer is built, a new layer is built on the previous one in the same way. Thus, the model is built layer by layer from the bottom to top.

为了大大缩短母模,模具和样件的制作时间,一些制造厂开始利用快速原型制造技术(RP)来制作复杂的母模和零

部件的原型。在过去的几年,各种新型的快速制造技术,通常称为快速成型制造(RP&M)已经出现.已开发的技术包括立体光刻(SL), 选择性激光烧结(SLS),熔融沉积制造(FDM),分层实体制造(LOM)和三维打印(3D Printing)。这些技术都是直接从CAD数据库生成物体的能力。它们都有一些共同的重要特征:原型件都是通过增材制造,而不是材料去除工艺制作的,也就是说,零件首先通过几何建模软件,如一个零件建模模块来建模,然后用数学的方法进行切层处理,使其成为一连串平行的横截面片,每一平行的横截面片固化的或者具有约束力的路径便生成了。这些固化的或具有约束力的路径就直接用于指导机器通过固化的或者具有约束力的线性层材料生产零部件。每建完一层材料实体,新一层材料实体就会以相同的形式建立在前一层材料实体上。因此,模型是从下到上一层一层建立起来的。

RP Processes 快速成型过程

As mentioned earlier, there are several technologies available for model production based on the principle of "growing" or "additive" manufacturing. The major differences among these technologies are in two aspects: (1) Materials used, and (2) Part building techniques. The following sections will explain in detail these rapid prototyping technologies with respect to the above two aspects.

如前所述,有几种技术的模型制作上载于“成长“或“添加剂“的制造原则为基础。在这些技术的主要区别是在两个方面:(1)所用材料,以及(2)零件创建技术。下面几节将详细说明就上述这些快速原型技术的两个方面。

1.Stereolithography 1.光固化成型机

Stereolithography apparatus (SLA) was invented by Charle Hull of 3D Systems Inc. It is the first commerically available rapid prototyper and is considered as the most widely used prototyping machine. The material used is liquid photo-curable resin. acrylate. Under the initialtion of photons, small molecules(monomers) are polymerized into large molecules. Based on this principle, the part is built in a vat of liquid resin as shown in Fig1.1.

光固化成型机是由3D System公司的Charle Hull发明。它是世界第一台使用最广的商业快速成型机。使用的材料为丙烯酸光敏树脂。在光子的引发下,小分子(单体)聚合成大分子。原型零件就是根据这一原理从树脂槽中制作出来的。如图1.1所示。

The SLA machine creates the prototype by tracing layer cross-section on the surface of the liquid photopolymer pool with a laser beam. Unlike the contouring or zigzag cutter movement used in CNC

machining, the beam traces in parallel lines. The laser beam is deflected horizontally in X and Y axes by galvanometer-driven mirrors so that it move across the surface of the resin to produce a solid pattern. After a layer is built, the elevator drops a user-specified distance and a new coating of liquid resin covers the solidified layer. A wiper helps spread the viscous polymer over for building the next layer. The laser draw a new layer on the top of the previous one. In this way, the model is built layer from bottom to top.

光固化成型机通过激光光束对液体感光树脂池面层的横截面进行跟踪的方式创建原型。同数控机床加工时刀具的轮廓走刀和循环走刀方式不一样,激光束是以平行方式扫描的。激光束通过振镜驱动水平在XY轴偏转,这样它跨越了树脂表面产生固体模型,创建好一层横截面片后,升降机下降一个用户指定的距离,新的液态树脂固化涂料就覆盖了上一个固化层,刮板用来将粘稠的树脂均匀涂覆在零件上表面以便于下一层的制作。激光在前一层的顶部进行新一层的扫描。这样原型就自下而上地逐层制作而成。

There are several features worthy of mentioning of SLA.

(1)Material.There are five commercially available photopolymers. All of them are a kind of acrylate.

(2)Support.Because a model is created in liquid, the overhanging regions of the part (unsupported below) may sag or float away during the building process. The prototye thus needs some predesigned support until it is cured or solidified. These additional features are built on the model parts and have to be trimmed after the model building is completed.

(3)Model accuracy and performance.The accuracy achieved is about 0.1% of the overall dimension and deteriorates with larger sizes but no more than 0.5%. The layer thickness is between 0.004¨ and 0.03¨. Presently, the SLA machines made by 3D Systems Inc. are the most accurate machines among the RP& M systems.

有很多值得一提的SLA几个特点。

(1)材质。有五个商用光聚合物。他们都是一类的丙烯酸酯。

(2)支持。由于模型是建立在液体之上的,零件的悬垂区域在创建过程中可能下垂或者漂浮。因此快速成型在零件凝固化或者固结家有时需要一些预先设计的支持。这些额外的特征是建立在模型零件之上的,所以必须在模型创建完成后对其进行必要的修剪。

(3)模型精度与性能。整体模型大小精度达到0.1%左右,当精度超过0.1%但不超过0.5%时就会恶化。每一截面层的厚度在0.004¨与0.03¨之间。目前,由3D System公司开发的SLA机械是RP&M系统中精度最高的机械。

2.Selective laser sintering(SLS) 选择性激光烧结(SLS)

SLS uses a carbon dioxide laser to sinter successive layers of powder instead of liquid.In SLS processes, a thin layer of powder is applied by a rotating roller mechanism onto the work place. The powder material is preheated to a temperature slightly below its melting point. The laser beam traces the cross-section on the powder surface to heat up the powder to the sintering temperature so that the powder scanned by the laser is bonded. The powder that is not scanned by the laser will remain in place to serve as the support to the next layer of powder, which aids in reducing distortion. When a layer of the cross-section is completed, the roller levels another layer of powder over the sintered one for the next pass. Fig.11.2 shows the working principle of SLS.

选择性激光烧结采用二氧化碳激光代替液体激光烧结粉末,在选择性激光烧结过程中,一层薄薄的的粉末采用一种旋转滚轴机制实用分布到工件上。该粉末材料预热到稍低于其熔点的温度。激光光速追踪粉末表面横截面的加热温度使表面温度达到烧结温度,这样就可以使得激光扫描的粉末结合。而对于未经过激光扫描的粉末将保留在原地以为支撑下一粉末层服务。这些粉末可辅助减少截面层的扭曲。当一个横截面层完成后,为了方便下一次通过已烧结的横截面层滚轴将新一层的粉末层与烧结层上一层对齐。图11.2显示了SLS的工作原理。

3.Fused deposition modeling(FDM) 熔融沉积制造(FDM)

In an FDM process as shown in Fig.11.3, a spool of thermoplastic filament feeds into a heated FDM extrusion head. The movement of the FDM head is controlled by computer. Inside the flying extrusion head, the filament is melted into liquid(1℃above the melting temperature) by a resistance heater. The head traces an exact outline of each cross-section layer of the part. As the head moves horizontally in X and Y axes, the thermoplastic material is extruded out of a nozzle by a precision pump. The material solidifies in 1/10 second as it is directed onto the workplace. After one layer is finished. the extrusion head moves up a programmed distance in Z direction for building the next layer. Each layer is bonded to the previous layer through thermal heating.

图11.3中显示了熔融沉积制造的过程。一卷热塑性长丝进给挤压进一个加热的FDM挤压头。FDM的头部运动由电脑控制,在高速运动的挤压头里,丝材被电阻加热到融化成液态(高于熔点1℃).挤压头精确按零件截面轮廓形状移动(从而逐层将原型零件制作出来)。随着挤压头小平地在XY轴上移动,热塑性材料通过一个精密泵挤压出一个喷嘴。随着材料接触到工件,热塑性材料将在1/10内凝结。当一层完成后,为创建下一层挤压头在Z轴方向移动一个已编程好的距离。通过热电阻加热,每一层材料都与上一层材料很好的结合。

https://www.wendangku.net/doc/9d10963176.html,minated object manufacturing(LOM) 分层实体制造(LOM)

The LOM processes produce parts from bonded paper plastic, metal or composite sheet stock. LOM machines bond a layer of sheet material to a stack of previously formed laminations, and then a laser beam follows the contour of the part cross-section generated by CAD to cut it to the required shape. The layers can be glued or welded together and the excess material of every sheet is either removed by vacuum suction or remains as next layer's support. Fig.11.4 shows the working principle of LOM.

在分层实体制造过程中,通过将纸质塑料,金属或者复合薄板材料进行结合生产零件。分层实体制造机将一层薄板材料与先前生成的叠片结构结合,然后采用激光光束沿着由CAD产生的零件横截面轮廓切出所需的形状。叠片层可以通过粘合或者焊接在一起,每片多余的材料可以采用真空抽取的方法去除也可以保留作为下一层的支撑。图11.4显示了分层实体制造(LOM)的工作原理。

5.Three-dimensional printing(3D Printing) 三维打印

Three-dimensional printing was developed at Massachusetts Institute of Technology. In the 3D printing process, a 3D model is sliced into2D cross-section layers in a computer. A layer of powder is spread on the top of the pistom, the powder bed, in a cylinder, and then an ink-jet printing head projects droplets of binder material onto the powder at the place where the solidification is required according to the information from the computer model. After one layer is completed, the piston drops a predefined distance and a new layer of powder is spread out and selectively glued. When the whole part completed, heat treatment is required to enhance the bonding of the glued powder, and then the unbounded powder is removed. FIg.11.5 showns the working process of 3D Printing.

三维打印技术是由美国麻省理工学院开发出来的。在三维打印过程中,计算机中的三维模型被切成二维横截面层,

首先在气缸的活塞(粉料床)顶部铺上一层粉末,然后一个喷墨打印头根据计算机模型信息在要求固化的粉末部分表面喷上粘结材料。一层完成后,活塞下降预定距离,新层粉末分散开并进行选择性的粘合。当整个零件完成后,为增加粘合粉末的粘合需要对零件进行热处理,热处理后无粘性的粉末也被移除。图11.5显示了三维打印的工作原理。

Current Applications of RP&M 快速成型技术的应用现状

A large number of industrial companies such as Texas Instruments, Inc., Chrysler Corporation, Amp Inc. and Ford Motor Co. have benefited from applying the technologies to improve their product development in the following three aspects.

许许多多的公司如得克萨斯仪器公司,克莱斯勒公司,AMP公司和福特汽车公司工业公司得益于应用技术以提高其在以下三个方面的产品开发。

1.Design engineering 设计工程

(1)Visualization. Conceptual models are very important in product design. The touch of the physical objects can reveal unanticipated problems and sometimes spark a better design. With RP&P, the prototype of a complex part can be built in a short time, therefore engineers can evaluate a design very quickly.

(1)可视化。在产品设计过程中概念模型是非常重要的。触摸真实的物理实体可以暴露某些无法预料的问题,有时还会引发出更好的设计。随着快速成型技术的发展,一个复杂的零件原型可以在短时间内完成,因此工程师们可以很快的对设计进行评估。

(2)Verification and optimization 验证和优化

Improving product quality is always an important issue of manufacturing. With the traditional method, developing of prototypes to validate or optimize a design is often time-consuming and costly. In contrast, an RP&M prototype can be produced quickly without substantial tooling and labour cost. Consequently, the verification of design concepts becomes simple: the product quality can be improved within the limited time and with affordable cost.

提高产品质量始终是制造业的重要问题。采用传统的方法来验证原型开发或优化设计往往是费时又费钱。与此相反,快速原型制造原型可以快速的生产,没有大量的工具和劳动成本的消耗。因此,设计概念验证变得简单:产品质量可以在有限的时间和可承受的成本范围内得到提高。

(3)Iteration 迭代

Just like the automotive industry manufacturers often put new product models into market. With RP& M technology, it is possible to go through multiple design iterations within a short time and substantially reduce the model development time.

就像一些汽车行业的制造商经常将新产品投入到市场中。有了快速原型与制造技术,就有可能在较短时间里通过多次设计迭代,从而大大减少模型的开发周期。

2.Manufacturing 制造

We can use the RP&M prototype for producibility studies. By providing a physical product at an earlier design stage, we can speed up process planning and tooling design. In addtion, by accurately describing complex geometry, the prototype can help reduce problems in interpreting the blue prints on the shop floor. Another application is tooling development for moulds.The prototypes can also be used as master patterns for castings.

我们可以利用RP&M原型进行生产研究。在早期设计阶段通过提供一个实体产品,我们就可以加速过程规划与工具的设计。此外,在工厂内原型可以帮助减少工程图翻译问题。另一个应用是工装模具的开发。该原型也可以用作铸件主模式。

3.Marketing 市场

To assist product sales, a prototype can be used to demonstrate the concept, design ideas, as well as the company's ability to produce it. Also, the prototype can be used to gain customers' feedback for design modifications so that the final product will meet customers' requirements. Meeting customers' demands in a timely manner is the key to penetrating the market in today's economy.

为了帮助产品销售,原型可用来验证设计概念,设计思路以及公司的生产能力。此外,原型可以用来获得客户对设计的修改意见,使最终产品满足客户的需求。在今天的经济市场情况下,及时地迎合顾客的需求是打入市场的关键。

《机械工程专业英语教程》课文翻译

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机械工程英语翻译

Unit1 1、What is the difference between an alloy and a pure metal? Pure metals are elements which come from a particular area of the periodic table. Examples of pure metals include copper in electrical wires and aluminum in cooking foil and beverage cans. 合金与纯金属的区别是什么?纯金属是在元素周期表中占据特定位置的元素。例如电线中的铜和制造烹饪箔及饮料罐的铝。 Alloys contain more than one metallic element. Their properties can be changed by changing the elements present in the alloy. Examples of metal alloys include stainless steel which is an alloy of iron, nickel, and chromium; and gold jewelry which usually contains an alloy of gold and nickel. 合金包含不止一种金属元素。合金的性质能通过改变其中存在的元素而改变。金属合金的例子有:不锈钢是一种铁、镍、铬的合金,以及金饰品通常含有金镍合金。 2、 Why are metals and alloys used? Many metals and alloys have high densities and are used in applications which require a high mass-to-volume ratio. 为什么要使用金属和合金?许多金属和合金具有高密度,因此被用在需要较高质量体积比的场合。 Some metal alloys,such as those based on aluminum, have low densities and are used in aerospace applications for fuel economy. Many alloys also have high fracture toughness, which means they can withstand impact and are durable. 某些金属合金,例如铝基合金,其密度低,可用于航空航天以节约燃料。许多合金还具有高断裂韧性,这意味着它们能经得起冲击并且是耐用的。 3、The atomic bonding of metals also affects their properties. In m etals, the outer valence electrons are shared among all atoms, and ar e free to travel everywhere. Since electrons conduct heat and electri city, metals make good cooking pans and electrical wires. 金属的原子连结对它们的特性也有影响。在金属内部,原子的外层阶电子由所有原子共享并能到处自由移动。由于电子能导热和导电,所以用金属可以制造好的烹饪锅和电线。 It is impossible to see through metals, since these valence electrons absorb any photons of light which reach the metal. No photons pass through. 因为这些阶电子吸收到达金属的光子,所以透过金属不可能看得见。没有光子能通过金属. 4、Some of the useful properties of ceramics and glasses include high melting temperature, low density, high strength, stiffness, hardness, wear resistance, and corrosion resistance. 陶瓷和玻璃的特性高熔点、低密度、高强度、高刚度、高硬度、高耐磨性和

机械工程专业英语翻译 华中科技大学版 李光布

1.机械设计过程 机械设计的最终目标是生产一种满足客户需求的有用产品,而且这种产品安全,高效,可靠,经济,实用。当回答这个问题时,广泛地思考,我将要设计的产品或系统的客户是谁? 在产品设计之前,了解所有客户的期望和期望是至关重要的。营销专业人员经常被用来管理客户期望的定义,但是设计师可能会把他们作为产品开发团队的一部分。 许多方法被用来确定客户想要什么。一种被称为质量功能部署或QFD的流行方法寻求(1)识别客户期望的所有特征和性能因素,以及(2)评估这些因素的相对重要性。QFD过程的结果是产品的一组详细功能和设计要求。 考虑设计过程如何配合为客户提供令人满意的产品所必须发生的所有功能以及在产品的整个生命周期中为产品提供服务也很重要。事实上,重要的是考虑产品在使用寿命后如何处置。影响产品的所有这些功能的总和有时被称为产品实现过程或PRP。PRP中包含的一些因素如下: ?营销功能来评估客户的要求 ?研究确定可在产品中合理使用的可用技术 ?可以包含在产品中的材料和组件的可用性 ?产品设计和开发 ?性能测试 ?设计文件 ?供应商关系和采购职能 ?考虑全球材料采购和全球营销 参加工作的技能 ?物理工厂和设施可用

?制造系统的能力 生产计划和生产系统的控制 ?生产支持系统和人员 ?质量体系要求 ?销售操作和时间表 ?成本目标和其他竞争性问题 ?客户服务要求 ?产品在生产,操作和处置过程中的环境问题 ?法律要求 ?金融资本的可用性 你可以添加到这个列表吗?您应该能够看到,产品的设计只是综合过程的一部分。在本文中,我们将更加注意设计过程本身,但必须始终考虑设计的可生产性。产品设计和制造过程设计的同时考虑通常被称为并行工程。 2.机械设计所需的技能 产品工程师和机械设计师在日常工作中使用广泛的技能和知识。这些技能和知识包含在以下内容中: ?素描,技术制图和计算机辅助设计 ?材料的性质?材料加工*和制造过程 ?化学的应用,如腐蚀防护,电镀和喷漆 静力学动力学材料的强度,运动学和机制 流体力学,热力学和传热 ?流体动力,电气现象的基本原理和工业控制

机械工程专业英语翻译合集

1.我们可以把钢再次加热到临界温度以下的某一温度,然后在慢慢让其冷却。We can heat the steel again to a temperature below the critical temperature, then cool it slowly. 2.无论任何简单的机床,都是由单一元件即通称为机械零件或部件组成的。However simple, any machine is a combination of individual components generally referred to as machine elements or parts. 3.这些金属不都是好的导体。 All these metals are not good conductors. 4. 在做带电实验的时候,再怎么小心都不为过。 You can't be too careful in performing an experiment. 5.利用发电机可以把机械能转变成电能。 The mechanical energy can be changed back into electrical energy by means of a generator or dynamo. 6.假定电源输入的电压保持不变。 Assume that the voltage input of the power supply remains the same. 7.化石燃料是发电过程中最为频繁使用的能源。 Fossil fuels are most frequently used source daring the power generation process. 8单个机械零件的可靠性成为评估整台机器使用寿命的基本因素。 The individual reliability of machine elements becomes the basis for estimating the overall life 9.说我们生活在一个电子时代,这一点都不夸张。 It's no exaggeration to say that we live in an electronic age. 10.发动机的转速不应超过最大允许值。 Engine revolution should not exceed the maximum permissible. 11.如能从大型核电站获得成本极低的电力,电解氢的竞争能力就会增强。(Electrolytic hydrogen)。 If extremely low-cost power were ever to become available from large nuclear power plants, electrolytic hydrogen would become competitive. 12.电子技术提供了一种新的显示时间的方法。 A new way of displaying time has been given by electronics. 13.远距离输电需要高压,安全用电需要低压。 High voltage is necessary for long transmission line while low voltage for safe use. 14.铝的电阻大约是同等尺寸的铜的1.5倍。 The resistance of aluminum is approximately half again as great as that of copper for the same dimensions = size 15.In fact,it is impossible for no force to be exerted on a body,since in this world everything is subject to the for ce of gravity. 事实上,物体不受外力作用是不可能的,因为在这个世界上任何物体都要受到重力的作用。 16.In a thermal power plant,all the chemical energy is not

(完整版)机械工程专业英语词汇

陶瓷ceramics 合成纤维synthetic fibre 电化学腐蚀electrochemical corrosion 车架automotive chassis 悬架suspension 转向器redirector 变速器speed changer 板料冲压sheet metal parts 孔加工spot facing machining 车间workshop 工程技术人员engineer 气动夹紧pneuma lock 数学模型mathematical model 画法几何descriptive geometry 机械制图Mechanical drawing 投影projection 视图view 剖视图profile chart 标准件standard component 零件图part drawing 装配图assembly drawing 尺寸标注size marking 技术要求technical requirements 刚度rigidity 内力internal force 位移displacement 截面section 疲劳极限fatigue limit 断裂fracture 塑性变形plastic distortion 脆性材料brittleness material 刚度准则rigidity criterion 垫圈washer 垫片spacer 直齿圆柱齿轮straight toothed spur gear 斜齿圆柱齿轮helical-spur gear 直齿锥齿轮straight bevel gear 运动简图kinematic sketch 齿轮齿条pinion and rack 蜗杆蜗轮worm and worm gear 虚约束passive constraint 曲柄crank 摇杆racker 凸轮cams

机械工程专业英语 翻译

2、应力和应变 在任何工程结构中独立的部件或构件将承受来自于部件的使用状况或工作的外部环境的外力作用。如果组件就处于平衡状态,由此而来的各种外力将会为零,但尽管如此,它们共同作用部件的载荷易于使部件变形同时在材料里面产生相应的内力。 有很多不同负载可以应用于构件的方式。负荷根据相应时间的不同可分为: (a)静态负荷是一种在相对较短的时间内逐步达到平衡的应用载荷。 (b)持续负载是一种在很长一段时间为一个常数的载荷, 例如结构的重量。这种类型的载荷以相同的方式作为一个静态负荷; 然而,对一些材料与温度和压力的条件下,短时间的载荷和长时间的载荷抵抗失效的能力可能是不同的。 (c)冲击载荷是一种快速载荷(一种能量载荷)。振动通常导致一个冲击载荷, 一般平衡是不能建立的直到通过自然的阻尼力的作用使振动停止的时候。 (d)重复载荷是一种被应用和去除千万次的载荷。 (e)疲劳载荷或交变载荷是一种大小和设计随时间不断变化的载荷。 上面已经提到,作用于物体的外力与在材料里面产生的相应内力平衡。因此,如果一个杆受到一个均匀的拉伸和压缩,也就是说, 一个力,均匀分布于一截面,那么产生的内力也均匀分布并且可以说杆是受到一个均匀的正常应力,应力被定义为 应力==负载 P /压力 A, 因此根据载荷的性质应力是可以压缩或拉伸的,并被度量为牛顿每平方米或它的倍数。 如果一个杆受到轴向载荷,即是应力,那么杆的长度会改变。如果杆的初始长度L和改变量△L已知,产生的应力定义如下: 应力==改变长△L /初始长 L 因此应力是一个测量材料变形和无量纲的物理量 ,即它没有单位;它只是两个相同单位的物理量的比值。 一般来说,在实践中,在荷载作用下材料的延伸是非常小的, 测量的应力以*10-6的形式是方便的, 即微应变, 使用的符号也相应成为ue。 从某种意义上说,拉伸应力与应变被认为是正的。压缩应力与应变被认为是负的。因此负应力使长度减小。 当负载移除时,如果材料回复到初始的,无负载时的尺寸时,我们就说它是具有弹性的。一特定形式的适用于大范围的工程材料至少工程材料受载荷的大部分的弹性, 产生正比于负载的变形。由于载荷正比于载荷所产生的压力并且变形正比于应变, 这也说明,当材料是弹性的时候, 应力与应变成正比。因此胡克定律陈述, 应力正比于应变。 这定律服从于大部分铁合金在特定的范围内, 甚至以其合理的准确性可以假定适用于其他工程材料比如混凝土,木材,非铁合金。 当一个材料是弹性的时候,当载荷消除之后,任何负载所产生的变形可以完全恢复,没有永久的变形。

机械工程英语翻译unit 1

Types of Materials 材料的类型 Materials may be grouped in several ways. Scientists often classify materials by their state: solid, liquid, or gas. They also separate them into organic (once living) and inorganic (never living) materials. 材料可以按多种方法分类。科学家常根据状态将材料分为:固体、液体或气体。他们也把材料分为有机材料(曾经有生命的)和无机材料(从未有生命的)。 For industrial purposes, materials are divided into engineering materials or nonengineering materials. Engineering materials are those used in manufacture and become parts of products. 就工业效用而言,材料被分为工程材料和非工程材料。那些用于加工制造并成为产品组成部分的就是工程材料。Nonengineering materials are the chemicals, fuels, lubricants, and other materials used in the manufacturing process, which do not become part of the product. 非工程材料则是化学品、燃料、润滑剂以及其它用于加工制造过程但不成为产品组成部分的材料。 Engineering materials may be further subdivided into: ①Metal ②Ceramics ③Composite ④Polymers, etc. 工程材料还能进一步细分为:①金属材料②陶瓷材料③复合材料④聚合材料,等等。 Metals and Metal Alloys 金属和金属合金 Metals are elements that generally have good electrical and thermal conductivity. Many metals have high

机械工程专业英语单词

Lesson 1 Basic Concepts in Mechanics 机械学的基本概念 mechanics n.力学 modify v.修改,调解,变更manageable a.可控制【管理】的 incline v.(使)倾斜 ramp n.斜板,斜坡【道】 slope v.(使)倾斜 friction n.摩擦 roll v.滚动 multiplier n.放大器,乘法器 broom n.扫帚 convert v.转变【化】 handle n.手柄【把】 sweep v.扫荡【描】,掠过efficiency n.效率 gauge vt.测【计】量,校验bearing n.轴承 ideal mechanical advantage 理想的机械效益 neglect vt.忽略Lesson 2 Basic Assumption in Plasticity Theory 塑性理论的基本假设 assumption n.假定 plasticity n.塑性 investigate v.调查,研究deformation n.变形 metal forming process 金属成型工艺【过程】 strain (rate) n.应变【速率】 strength n.强度 stress n.应力 yield stress 屈服应力 flow stress 流动应力 tensile stress 拉【伸】应力compressive stress 压【缩】应力 shear stress 剪【切】应力 geometry n.几何形状 elastic a.弹性的 springback n.回弹 bending n.弯曲,折弯

机械工程专业英语第二版必考翻译(完整版)

1.With low-power machinery or vehicles the operator can usually apply sufficient force through a simple mechanical linkage from the pedle or handle to the stationary part of the brake. In many cases, however, this force must be multiplied by using an elaborate braking system.(P5)用低能机器或传力工具,操作者通过向踏板或把手的一个简单机械连接构件作用足够的力量到车闸固定的部分。大多数情况,然而,用一个详细(复杂)的车闸系统使这个力量成倍增加。 2. The fundamental principle involved is the use of compressed air acting through a piston in a cylinder to set block brakes on the wheels. The action is simultaneous o n the wheels of all the cars in the train. The compressed air is carried through a strong hose from car to car with couplings between cars; its release to all the separate block brake units, at the same time, is controlled by the engineer. (Braking Systems)(P5) 相关的基本原理是使用压缩气体,通过气缸内的活塞将闸块压在车轮起作用。列车的所有车厢上的车轮同时动作。压缩气体通过一个坚固的管道在由联轴器连接的车厢之间传输;工程师控制其在同一时间释放到所有独立的闸块单元。 3.When the brake pedal of an automobile is depressed, a force is applied to a piston in a master cylinder. The piston forces hydraulic fluid through metal tubing into a cylinder in each wheel where the fluid’s pressure moves two pistons that press the brake shoes against the drum. (Braking Systems)(P5) 当踩下汽车刹车的踏板,在主汽缸中的活塞上施加一个力。活塞驱动液压流体通过金属管道进入每个车轮气缸,在那里液压移动两个活塞将闸片压向轮圈。 4.Machinery ontology including mechanical rack, mechanical connections and mechanical transmission, which is the basis of mechanical-electrical integration, plays a role in supporting the other functional units of the system and transmitting motion and power. Compared to purely mechanical products, the performance and functionality of integration technology in electrical and mechanical systems have been improved a lot, which requires mechanical ontology to adapt its new status in mechanical structure, materials, processing technology, as well as the areas of geometry. Accordingly, the new ontology is with high efficient, multi-functional, reliable and energy-saving, small, light-weighted and aesthetically pleasing characteristics. (Mechatronics System) (P7) 机械体包括机架、机械联接和机械传动,它是机电一体化的基础,作用是支撑系统其他功能单元,传递运动和动力。和纯机械产品相比,一体化技术的性能和功能在机电系统中大幅提高,它要求机械本体适应在机械结构、材料、加工技术以及这些领域中的几何学下的新环境。相应的,新的一体化具有高效、多功能、可靠、节能、小轻和美学的令人赏心悦目的特征。 5. Detecting sensor detecting sensor part includes a variety of sensors and signal detection circuit, and its function is to detect the process of mechatronic systems in the work itself and the changes of relevant parameters in external environment and transmit the information to the electronic control unit. Electronic control unit check the information and sends the corresponding control issues to the actuator. (Mechatronics System) (P7) 检测传感器部分包括各类传感器、信号检测电路,它的功能是检测机电系统自身工作的工程,在外部环境下的相关参数的改变,将其信息传给电子控制单元。电子控制单元通过检查信息,送出相应的指令到执行机构。 6. Electronic control unit, also known as ECU, is the core of mechatronic systems, responsible for the external commands and the signals output by sensors. It centralizes stores, computes and analyzes the information. Based on the results of information processing,instruction are issued according to a certain extent and pace to control the destination for the entire system. (Mechatronics System) (P7) 电子控制单元,也被称为控制单元(ECU)控制,是机电系统的核心,负责外部命令和传感器的信号输出。它集中、存储、计算并分析信息。基于信息处理的结果,按照一定的范围和步调发出命令来实现控制整个系统的目标。 7. It is put into a fairly standard machine tool that has had position sensing and motors on the

机械专业术语英文翻译

机械专业英语词汇 陶瓷ceramics 合成纤维synthetic fibre 电化学腐蚀electrochemical corrosion 车架automotive chassis 悬架suspension 转向器redirector 变速器speed changer 板料冲压sheet metal parts 孔加工spot facing machining 车间workshop 工程技术人员engineer 气动夹紧pneuma lock 数学模型mathematical model 画法几何descriptive geometry 机械制图Mechanical drawing 投影projection 视图view 剖视图profile chart 标准件standard component 零件图part drawing 装配图assembly drawing 尺寸标注size marking 技术要求technical requirements 刚度rigidity 内力internal force 位移displacement 截面section 疲劳极限fatigue limit 断裂fracture 塑性变形plastic distortion 脆性材料brittleness material 刚度准则rigidity criterion 垫圈washer 垫片spacer 直齿圆柱齿轮straight toothed spur gear 斜齿圆柱齿轮helical-spur gear 直齿锥齿轮straight bevel gear 运动简图kinematic sketch 齿轮齿条pinion and rack 蜗杆蜗轮worm and worm gear 虚约束passive constraint 曲柄crank 摇杆racker

机械专业英语复试词汇总结

机械英语词汇大全2 金属切削 metal cutting 机床 machine tool 金属工艺学 technology of metals 刀具 cutter 摩擦 friction 联结 link 传动 drive/transmission 轴 shaft 弹性 elasticity 频率特性 frequency characteristic 误差 error 响应 response 定位 allocation 拉孔 broaching 装配 assembling 铸造 found 流体动力学 fluid dynamics 流体力学 fluid mechanics 加工 machining 液压 hydraulic pressure 切线 tangent 机电一体化 mechanotronics mechanical-electrical integration 气压 air pressure pneumatic pressure 稳定性 stability 介质 medium 数学模型 mathematical model 画法几何 descriptive geometry 机械制图 Mechanical drawing 投影 projection 视图 view 剖视图 profile chart 标准件 standard component 零件图 part drawing 装配图 assembly drawing 尺寸标注 size marking 技术要求 technical

机床夹具 jig 动力学 dynamic 运动学 kinematic 静力学 static 分析力学 analyse mechanics 拉伸 pulling 压缩 hitting 剪切 shear 扭转 twist 弯曲应力 bending stress 强度 intensity 三相交流电 three-phase AC 磁路 magnetic circles 变压器 transformer 异步电动机 asynchronous motor 液压驱动泵 fluid clutch 液压泵 hydraulic pump 阀门 valve 失效 invalidation 强度 intensity 载荷 load 应力 stress 安全系数 safty factor 可靠性 reliability 螺纹 thread 螺旋 helix 键 spline 销 pin 滚动轴承 rolling bearing 滑动轴承 sliding bearing requirements 刚度 rigidity 内力 internal force 位移 displacement 截面 section 疲劳极限 fatigue limit 断裂 fracture 塑性变形 plastic distortion 脆性材料 brittleness material 刚度准则 rigidity criterion 垫圈 washer 垫片 spacer 直齿圆柱齿轮

机械工程专业英语参考译文

机械工程专业英语》参考译文 高等学校机械设计制造及其自动化专业新编系列教材(供教师及学生使用) 黄运尧黄威 司徒忠李翠琼 武汉理工大学出版社 目录编译者的话……………………………… 第1章材料和热加工………………… 第1课机械学的基本概念………… 第2课塑性理论的基本假设……… 第3课有限元优化的应用………… 第4课金属………………………… 第5课金属和非金属材料………… 第6课塑料和其他材料…………… 第7课模具的寿命和失效………… 第8踩冷加工和热加工…………… 第9踩铸造………………………… 第10课制造中的金属成形工艺… 第11课缎选……………………… 第12课锻造的优点和工作原理… 第13课焊接……………………… 第14课热处理…………………… 第二章机构和机器原理……………。 第15课机构介绍…………………。 第16课运动分析…………………. 第l7课运动的综合………………— 第18课凸轮和齿轮………………— 第19课螺纹件,紧固件和联接件— 第20课减(耐)摩擦轴承…………*第2l课斜齿轮、蜗杆蜗轮和锥齿轮 第22课轴、离合器和制动器……— 第三章机床……… 第23课机床基础 第24课车床…… 第25课牛头刨、钻床和铣床…………第36课磨床和特种金属加工工艺……第四章切削技术和液压“………………第27课加工基础………………………第28课基本的机械加工参数…………第29课切削参数的改变对温度的影响第30课刀具的磨损………… 第31课表面稍整加工机理… 第32课极限和公差…………“

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机械英文翻译

机械英文翻译

英文翻译 机械设计 一台完整机器的设计是一个复杂的过程。机械设计是一项创造性的工作。设计工程师不仅在工作上要有创造性,还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚的基础知识。 Machine Design The complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. 任何产品在设计时第一步就是选择产品每个部分的构成材料。许多的材料被今天的设计师所使用。对产品的功能,它的外观、材料的成本、制造的成本作出必要的选择是十分重要的。对材料的特性必须事先作出仔细的评估。 One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations. 仔细精确的计算是必要的,以确保设计的有效性。在任何失败的情况下,最好知道在最初设计中有有缺陷的部件。计算(图纸尺寸)检查是非常重要的。一个小数点的位置放错,就可以导致一个本可以完成的项目失败。设计工作的各个方面都应该检查和复查。 Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked. 计算机是一种工具,它能够帮助机械设计师减轻繁琐的计算,并对现有数据提供进一步的分析。互动系统基于计算机的能力,已经使计算机辅助设计(CAD)和计算机辅助制造(CAM)成为了可能。心理学家经常谈论如何使人们适应他们所操作的机器。设计人员的基本职责是努力使机器来适应人们。这并不是一项容易的工作,因为实际上并不存在着一个对所有人来说都是最优的操作范围和

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