科技英语-钢的热处理PPT格式课件下载.ppt

1、淬火处理是指将钢材加热到其临界区之上，然后降温即在适当的介质如水、盐水、油或其它液体中使之迅速冷却。,critical range：临界区,quench,2.淬 火 hardening,quench：v.淬火、熄灭,brine：n.盐水,Heat Treatment of Steel钢的热处理,consists of 组成，构成，包括，由组成1.The United Kingdom consists of Great Britain and Northern Ireland.联合王国包括大不列颠与北爱尔兰。2.His job consists of helping old people who

2、 live alone.他的工作包括帮助无人照顾的独居老人。3.Substances consist of small particles called molecules.物质是由叫做分子的微粒组成的。,Heat Treatment of Steel钢的热处理,Having been hardened,the metal must be given a tempering treatment which consists of reheating the hardened steel to a temperature below the critical range,thus produci

3、ng the required physical properties.,临界区以下的某个温度,译文：金属淬硬之后必须进行回火处理，回火是将淬硬的钢重新加热到低于临界区的某个温度，从而获得所需的物理性能。,3.回 火tempering,完成时态表明回火（temper）操作在淬火（harden）之后。,Heat Treatment of Steel钢的热处理,一、广泛使用被动语句根据英国利兹大学John Swales 的统计，科技英语中的谓语至少三分之一是被动态。这是因为科技文章侧重叙事推理，强调客观准确。第一、二人称使用过多，会造成主观臆断的印象。因此尽量使用第三人称叙述，采用被动语态，例如：

4、Attention must be paid to the working temperature of the machine.应当注意机器的工作温度。而很少说：You must pay attention to the working temperature of the machine.你们必须注意机器的工作温度。此外，科技文章将主要信息前置，放在主语部分。这也是广泛使用被动态的主要原因。,科技英语的特点（一）,Heat Treatment of Steel钢的热处理,科技英语的特点（一）,二、后置定语大量使用后置定语也是科技英语的特点之一。常见的结构不外以下五种：1、The force

5、s due to friction are called frictional forces.（介词短语）2、In this factory the only fuel available is coal.（形容词及形容词短语）3、The force upward equals the force downward so that the balloon stays at the level.（副词）4、The results obtained must be cheeked.（单个分词），5、During construction,problems often arise which req

6、uire design changes.（定语从句）在施工过程中，常会出现需要改变设计的问题。,Heat Treatment of Steel钢的热处理,Annealing is the uniform heating of a metal above usual hardening temperatures,followed by very slow cooling.,译文：退火指的是在通常的淬火温度之上将金属均匀的加热，然后再缓慢的冷却。,4.退 火annealing,Heat Treatment of Steel钢的热处理,科技英语的特点（一）,三、大量使用名词化结构大量使用名词化结构（

7、Nominalization）是科技英语的特点之一。因为科技文体要求行文简洁、表达客观、内容确切、信息量大、强调存在的事实。Archimeds first discovered the principle of displacement of water by solid bodies.阿基米德最先发展固体排水的原理。科技英语所表述的是客观规律，因之要尽量避免使用第一、二人称；此外，如前所述，要使主要的信息置于句首。Television is the transmission and reception of images of moving objects by radio waves.电视

8、通过无线电波发射和接受活动物体的图象。,Annealing may be carried out either to soften a piece that is too hard to machine or to remachine a piece that has already been hardened.Annealing also relieves internal stresses produced by machining.,重新机加工,译文：若工件过硬以致无法机加工，或是要重新机加工已经淬火变硬的工件，就可通过退火来使材料软化。退火也可以减轻因为机加工而造成的内应力。,内应力,

9、4.退 火annealing,Heat Treatment of Steel钢的热处理,Heat Treatment of Steel钢的热处理,5.表面热处理surface heattreatment,Low carbon steel do not become hard when subjected to such a heat treatment because of the small amount of carbon contained.If it is necessary to obtain a hard surface on a part made of such steel,s

10、urface hardening operation must be carried out.,低碳钢,Low carbon steel,表面硬化、表面淬火,译文：低碳钢因为含碳量少所以在经受这种热处理后并不会变硬。如果这种钢材制成的某个零件有必要得到一个较硬的表面，就必须进行表面淬火处理。,cyanide v.氰化,Heat Treatment of Steel钢的热处理,6.氰 化cyaniding,One of the methods of surface hardening is cyaniding,which is done by keeping the work in a molt

11、en bath of sodium cyanide from 5 to 30 minutes,depending on the size of the work and the depth of penetration required.,sodium n.钠 sodium cyanide 氰化钠,译文：表面淬火的方法之一是氰化，即根据工件的尺寸和所要求的渗层深度将工件置于氰化钠熔池中保持5到30分钟。,工件（steel）,熔池,Having been subjected to such a treatment,the work is then quenched in water or oil

12、,and a very hard case 0.01 to 0.015 inch thick is formed.This process is also called case hardening.,Heat Treatment of Steel钢的热处理,6.氰 化cyaniding,将工件置于氰化钠熔池中的氰化处理,表面硬化 equals to surface harden,译文：工件经过这样的处理后被置于水或油中冷却，就可以形成一0.01到0.015英寸厚的硬度层，这一过程也被称为表面淬火。,Heat Treatment of Steel钢的热处理,7.渗 氮nitriding,Nit

13、riding is also one of the case hardening methods.This process consists of keeping the steel in hot ammonia gas for some hours.Nitrogen,formed in this condition from ammonia,penetrates into the surface of the metal,thus forming a very hard case.,nitride v.渗氮,ammonia n.氨、氨水,nitrogen n.氮,译文：渗氮也是一种表面淬火方

14、法。其过程为将钢置于热的氨蒸气中保持数小时。氮-在该情形下来自于氨-便会渗入金属表面，形成一非常硬的表层。,Heat Treatment of Steel钢的热处理,8.渗 碳carburizaion,Another method of the case hardening is carburization.The work is placed into a metal box containing carburizing materials（that is materials with high carbon content）；the box is closed and placed int

15、o a furnace for some hours at the temperature of 926 degrees Centigrade.,carburization n.渗碳,摄氏度,译文：表面淬火的另一个方法是渗碳。工件被置于含渗碳材料（即含碳量很高的材料）的金属箱中。封闭箱子将其置于摄氏温度926的炉膛内数小时。,Heat Treatment of Steel钢的热处理,8.渗 碳carburizaion,The depth to which the carbon penetrates depends upon the length of time the piece is kep

16、t in the furnace.Having been quenched in some liquid quenching medium,the work has a hard case and a soft core.,取决于，=depend on,液体冷却介质,core n.中心，核心，芯部,译文：渗碳深度取决于工件在炉膛中保持的时间长度，经一些液体冷却介质冷却之后，工件便会形成坚硬的表面和较软的芯部。,基本概念钢的热处理（heat treatment of steel）普通热处理 normal heat treatment 1.淬火 hardening/quenching 2.回火 t

17、empering 3.退火 annealing表面热处理 surface heat treatment 1.氰化 cyaniding 2.渗氮 nitriding 3.渗碳 carburization,Heat Treatment of Steel,总 结,相关词汇1.钢的热处理：heat treatment of steel 2.淬火：quench/harden 3.回火：temper 4.退火：anneal 5.表面热处理：surface heat treatment6.表面硬化 表面淬火：surface/case harden 7.氰化：cyanide 8.氰化钠：sodium syan

18、ide 9.渗氮：nitride 10.氨水：ammonia11.氮：nitrogen 12.渗碳：carburization,Heat Treatment of Steel,总 结,Heat Treatment of Steel,总 结,科技英语的特点（一）,一、广泛使用被动语句is rapidly cooling in a suitable medium such as.The metal must be given a tempering treatment.Annealing may be carried out.The work is then quenched in二、后置定语.a tempering treatment which consists of.internal stresses produced by machining.a temperature below the critical range.三、大量使用名词化结构the physical properties of a metal.the uniform heating of a metal.,谢谢大家！,