機(jī)械工程專業(yè)英語教程（第２版）Lesson 46

1、Lesson 46 Machining of Engineering CeramicsTerminologyText tour 8/5/20221機(jī)械工程專業(yè)英語教程Terminology8/5/20222機(jī)械工程專業(yè)英語教程Ultrasonic machiningUltrasonic machining (USM) is a mechanical material removal process for brittle materials which uses high frequency oscillations of a shaped tool using an abrasive slu

2、rry.超聲加工: 超聲加工是一種使成型工具產(chǎn)生高頻振動(dòng)，通過懸浮磨料的作用對脆性材料采用機(jī)械方式進(jìn)行材料去除的過程。機(jī)械工程專業(yè)英語教程8/5/2022Slurry A thin mixture of a liquid, especially water, and any of several finely divided substances.懸浮液：一種液體，尤指水和幾種顆粒細(xì)小的物質(zhì)的較稀的混合物。 3Engineering ceramic materials have attractive properties: high hardness, high thermal resista

3、nce, chemical inertness, and low thermal or electrical conductivity, to name a few. However, these properties make ceramics extremely difficult to machine, whether by abrasive or nonabrasive processes.工程陶瓷材料具有許多引人注目的特性，諸如：高硬度，高耐熱性，化學(xué)惰性，低的導(dǎo)熱性和導(dǎo)電率等。然而，這些特性使得陶瓷的機(jī)械加工非常困難，不管是采用磨削或者非磨削的方法都是如此。機(jī)械工程專業(yè)英語教程8/

4、5/2022Text tour4Grinding involves a complex interaction between a number of variables: workpiece material properties, wheel specifications, machine tools selection, and wheel preparation. This interaction, called “grindability,”can be quantified in terms of material-removal rate, power or grinding f

5、orce required, surface roughness, tolerances, and surface integrity.磨削涉及到工件的材料性能、砂輪規(guī)格、機(jī)床的選擇與砂輪準(zhǔn)備等許多變量之間復(fù)雜的相互影響。這種相互影響叫做“磨削性”，它可以用材料去除速度、所需要的動(dòng)力或者磨削力、表面粗糙度、公差和表面完整性等項(xiàng)指標(biāo)的數(shù)量大小來表示。機(jī)械工程專業(yè)英語教程8/5/20225There are no heat effects nor large mechanical forces in water-jet machining, so that even the most therma

6、l-shock sensitive, weakest ceramics can be cut without damage. Chatter, vibration, surface distortion, and subsurface damage of the workpiece also are eliminated.水射流加工既無熱影響也不需要大的機(jī)械力，因此在切削對熱沖擊最敏感的和最脆弱的陶瓷時(shí)，都不會(huì)造成工件的損壞。這種加工方法可以避免產(chǎn)生顫振、振動(dòng)、工件的表面變形或表面層下的損傷。機(jī)械工程專業(yè)英語教程8/5/20226Ultrasonic machining is another

7、abrasive process that has certain advantages over conventional grinding. Sometimes called impact grinding, it is a mechanical process that uses a high frequency transducer. As the electrical energy is converted into mechanical motion, a low-amplitude vibrationis produced.超聲加工是另外一種磨削加工過程，它具有一些優(yōu)于常規(guī)磨削的

8、特點(diǎn)。超聲加工有時(shí)被稱為沖擊磨削，它是使用高頻換能器的一種機(jī)械加工過程。當(dāng)電能轉(zhuǎn)換為機(jī)械運(yùn)動(dòng)時(shí)，就會(huì)產(chǎn)生小振幅的振動(dòng)。機(jī)械工程專業(yè)英語教程8/5/20227Abrasionless machining, such as laser-beam and electron-beam machining (LBM, EBM), is not limited by the hardness of ceramics and therefore offers an alternative to conventional grinding. In LBM, a laser focuses an intense

9、 beam of light onto the workpiece to vaporize material. Because the laser beam is mechanically positioned, it is not as fast as EBM.非磨削加工，諸如激光束加工和電子束加工，不受陶瓷硬度的限制，因此可以用來代替常規(guī)磨削加工。在激光束加工中，激光器將能量密度高的光束聚焦在工件上，使工件材料蒸發(fā)。由于激光束是由機(jī)械定位的，因此沒有電子束加工快。8機(jī)械工程專業(yè)英語教程8/5/2022Machining rate is controlled by the rate at which material, which is melted and vaporized, is