专业英语翻译作业译文

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电子商务专业英语作业翻译

E-commerce (electronic commerce or EC) is the buying and selling of goods and services on the Internet, especially the World Wide Web. In practice, this term and a newer term, e-business, are often used interchangably. For online retail selling, the term e-tailing is sometimes used.电子商务（电子商务或电子商务）是购买和出售的商品和服务在互联网，特别是万维网上的。

在实践中，这项和一个新的术语，电子商务，往往交替使用。

网上零售，电子零售的术语有时用。

E-tailing or The Virtual Storefront and the Virtual Mall网上或虚拟商店和虚拟商店As a place for direct retail shopping, with its 24-hour availability, a global reach, the ability to interact and provide custom information and ordering, and multimedia prospects, the Web is rapidly becoming a multibillion dollar source of revenue for the world's businesses. A number of businesses already report considerable success. As early as the middle of 1997, Dell Computers reported orders of a million dollars a day. By early 1999, projected e-commerce revenues for business were in the billions of dollars and the stocks of companies deemed most adept at e-commerce were skyrocketing. Although many so-called dotcom retailers disappeared in the economic shakeout of 2000, Web retailing at sites such as , , and continues to grow.作为一个直接的零售购物，其24小时供应，全球性的，互动的能力，并提供自定义信息和订购，和多媒体，网络正在迅速成为一个数十亿美元的收入来源，为全球的企业。

专业英语原文和翻译

Basic Control Actions and Industrial Automatic Control An automatic controller compares the actual value of the plant output with the desired value, determines the deviation, and produces a control signal which will reduce the deviation to zero or to a small value.The manner in which the automatic conroller produces the control signal is called the control action.Classifications of industrial automatic controllers Induetrial automatic controllers may be classified according to their control action as:·two-position or on-off controllers;·proportional controllers;·integral controllers;·proportional-plus-integral controllers;·proportional-plus-derivative controllers;·proportional-plus-derivative-plus-integral controllers.Most industrial automatic controllers use eletricity or pressurized fluid such as oil or air as power sources. Automatic controllers may also be classified according to the kind of power employed in the operation, such as pneumatic controllers, hydraulic controllers, or electronic controllers.What kind of controller to use must be decided by the nature of the plant and the operating conditions,including such considerations as safety, availability, reliability, accuracy, weight, and size?Elements of industrial automatic controllers An automatic controller must detect the actuating error signal, which is usually at a very low power level, and amplify it to a sufficiently high level. Thus, an amplifier is necessary. The output of an automatic controller is fed to a power device, such as a pneumatic motor or valve, a hydraulic motor, or an electric motor.The controller usually consists of an error detector and amplifier. The measuring element is a device that converts the output variable into another suitable variable, such as a displacement, pressure, or electric signal, which can be used for comparing the output to the reference input signal. This element is in the feedback path of the closed-loop system. The set point of the controller must be converted to a reference input of the same units as the feedback signal from the measuring element. The amplifier amplifies the power of the actuating error signal, which in turn operates the actuator. The actuator is an element which alters the input to the plant according to the control signal so that the feedback signal may be brought into correspondence with the reference input signal.Self-operated controllers In most industrial automatic controllers, separate units are used for the measuring element and for the actuator. In a very simple one, however, such as a self-operated controller, these elements are assembled in one unit. Self-operated controllers utilize power developed by the measuring element and are very simple and inexpensive. The set point is determined by the adjustment of the spring force. The controlled pressure is measured by the diaphragm. The actuating error signal is the net force acting on the diaphragm. Its position determines the valve opening.The operation of self-operated controller is as follows: Suppose that the output pressure is lower than the reference pressure, as determined by the set point. Then the downward spring force is greater than the upward pressure force, resulting in a downward movement of the diaphragm. This increases the flow rate and raises the output pressure.When the upward pressure force equals the downward spring force, the valve plug stays stationary and the flow rate is constant. Comversely, if the output pressure is higher than the reference pressure, the valve opening becomes small and reduces the flow rate through the valve opening. Such a self-operated controller is widely used for water and gas pressure control. In such a controller, the flow rate through the valve opening is approximately proportional to the actuating error signal.Control actions The following six basic control actions are very common among industrial automatic controllers: two-position or on-off, proportional, integral, proportional-plus-integral,proportional-plus-derivative,andproportional-plus-derivative-plus-integral control action. Note that an understanding of the basic charateristics of the various actions is necessary in order for the control engineer to select the one best suited to his particular application.翻译：自动控制器把对象的实际输出与期望值进行比较，确定偏差，并产生一个使误差为零或微小值的控制信号。

英语专业八级翻译练习题英译汉

英语专业八级翻译练习题（一）The Rewards of Living a Solitary LifeThe other day an acquaintance of mine, a gregarious and charming man, told me he had found himself unexpectedly alone in New York for an hour or two between appointments. He went to the Whitney and spent the "empty" time looking at things in solitary bliss. For him it proved to be a shock nearly as great as falling in love to discover that he could enjoy himself so much alone.参考译文：独自生活的报偿前些日子，我的一个熟人，一位热爱交际并很受欢迎的男士告诉我，他在纽约的两个约会之间偶然有一两个小时的空闲，他便去了惠特尼博物馆，四处浏览着展品，无比幸福的度过了那些时光。

发现自已独自一人，也能如此的幸福，他感觉像坠入爱河那般震惊。

英语专业八级翻译练习题（二）What had he been afraid of, I asked myself? That, suddenly alone, he would discover that he bored himself, or that there was, quite simply, no self there to meet? But having taken the plunge, he is now on the brink of adventure; he is about to be launched into his own inner space to the astronaut. His every perception will come to him with a new freshness and, for a time, seem startlingly original.参考译文：“他一直在害怕什么呢？”，我问自已。

03南京邮电大学《专业英语》作业翻译

(14.2-5)
(r) [ +( (14.2-6)
假设
《k
将式14.2-4和式14.2-6代入式14.2-5得到
+c.c.+ +c.c.
+ u [ +( +c.c)]×[ + +c.c.]=0（14.2-7）
通过研究发现，当满足布拉格条件时，
K2-K1=K(14.2-8)
空间累积的能量交换就会发生。
(14.2-13)
其中
(14.2-14)
If we wish to reconstruct picture 1, we illuminate the hologram with the corresponding reference wave k2(ie, the same reference wave used to record it ),as discussed above.如果我们想重建图片1，我们照亮了相应的参考波幼（即相同的参考波用来记录它）全息图，如上所述。This reference wave will encounter in the crystal, not only the desired hologram n1(r) but also hologram n1(r).这将遇到参考波在晶体中，不仅所需的全息图n1（注册商标），而且也全息n1（注册商标）。Any light scattered from hologram n1(r) in the direction of k1 thus constitutes (noisy) crosstalk, which degrades the information contents of picture 1.从全息图n1分散的任何光线（r）在这样的k1构成（噪音）串扰，从而影响了图片1的信息内容的方向。This crosstalk places a fundamental limit on the number of holograms and their stored information contents.这种串扰重视数量的全息图的基本限制和所存储的信息内容。To quantify this argument, we will derive an expression for the power radiated along k1 due to the undesirable scattering of the reference beam employed (k2) off the“wrong”hologram of picture 2-n1(r).The equations describing this process were derived in (14.2-9) and are reproduced here for the incident (A2) and the diffracted (A1) beams ((((((((公式)))))))))) where the grating vector K=k2-k1 is that of hologram 2 and we took (())=0.The direction k1 is , according to Figure 14-6,the same for both n11(r) and n12(r),since the“picture”direction is the same for all the recorded holograms.为了量化这一论点，我们会得出一个沿k1由于就业（k2）的关闭“错误”的图片2全息图- n1参考光束不良散射辐射的功率表达式（注册商标）。该方程描述了这一进程衍生（14.2-9）和转载的事件（A2）和衍射（格A1）这里横梁

刚整理的专业英语课文翻译

第一单元Human bodyTo understand the human body it is necessary to understand how its parts are put together and how they function. The study of the body's structure is called anatomy; the study of the body's function is known as physiology. Other studies of human body include biology, cytology, embryology, histology, endocrinology, hematology, immunology, psychology etc.了解人体各部分的组成及其功能，对于认识人体是必需的。

研究人体结构的科学叫解剖学；研究人体功能的科学叫生理学。

其他研究人体的科学包括生物学、细胞学、胚胎学、组织学、内分泌学、血液学、遗传学、免疫学、心理学等等。

Anatomists find it useful to divide the human body into ten systems, that is, the skeletal system, the muscular system, the circulatory system, the respiratory system, the digestive system, the urinary system, the endocrine system, the nervous system, the reproductive system and the skin. The principal parts of each of these systems are described in this article.解剖学家发现把整个人体分成骨骼、肌肉、循环、呼吸、消化、泌尿、内分泌、神经、生殖系统以及感觉器官的做法是很有帮助的。

专业英语课文翻译

Lesson 1 Why GIS?现在，许多组织在地理信息系统和地理数据库方面花费大量的金钱。

预言显示，在整个下一个十年，将有数十亿美元花费在这些上面。

为什么在现今成为现实，而在仅仅几年前，GIS还是稀有之物？迅速下降的计算机硬件成本，使得能够负担得起GIS的人迅速增多，范围变广。

更重要的是，我们终于认识到，地理学（和数据描述的地理学）是我们日常生活环境的部分：几乎我们所做的每一个决策都是被一些地学事实所限制，所影响，或是所支配的。

我们派消防车以最快的速度，尽可能短的路径到达着火现场。

我们的中央政府经常根据人口数量拨款物给地方政府。

我们通过确认疾病的流行地区和传播速度来研究疾病。

这种对地理信息的需求与对GIS的需要相吻合，解释了它迅速普及的原因。

然而，如此概括不能够解释GIS为什么能帮助和怎样帮助你。

首先，你必须知道GIS 是什么和它能用来做什么。

下面的主题将帮助你理解GIS。

GIS是什么？在1980年代，GIS的使用显著地增长。

现在，对企业、政府和学术界来说，运用GIS 的许多不同的应用已是寻常之事。

因而GIS的许多定义已经出现了。

例如，翻到本书的词汇表，你将发现GIS被描述为：由计算机硬件、软件、地理数据和人员构成的有机集成，被设计来有效搜集、储存、更新、处理、分析和展示各种空间相关信息。

尽管这个定义正确、全面、并被广泛接受，但它对初学GIS的人帮助不多。

当你读完此工作手册，这个定义的含义将变得清晰，但目前，考虑一个更简单的定义：能够支持和使用数据描述地表区域的计算机系统。

空间操作许多计算机程序，诸如spreadsheets, statistics packages, 或drafting packages能处理简单的地理或空间数据，那么，为什么他们不是通常所认为的是GIS呢？一个通常被接受的回答是，如果它允许对数据进行空间操作，这样的GIS才是GIS。

作为一个例子，考虑下面的表格：这个表格表明，在所选择的活动中心，从事GIS某一方面工作者的大致数量。

机械工程专业英语_原文翻译

5.1 IntroductionConventional machining is the group of machining operations that use single- or multi-point tools to remove material in the form of chips. Metal cutting involves removing metal through machining operations. Machining traditionally takes place on lathes, drill presses, and milling machines with the use of various cutting tools. Most machining has very low set-up cost compared with forming, molding, and casting processes. However, machining is much more expensive for high volumes. Machining is necessary where tight tolerances on dimensions and finishes are required.5.1 译文传统机械加工是一组利用单刃或者多刃刀具以切屑形式去除材料的加工方式。

金属切削意味着通过机械加工去除金属。

传统的机械加工都是利用不同的刀具在车床、钻床和铣床上进行的。

与成型加工、锻压和铸造工艺相比，大多数机械加工的生产准备成本都较低，然而如果是大批量生产，其成本要高得多。

当对零件的尺寸公差和光洁度要求较高时，机械加工是很有必要的。

5.2 Turning and LatheTurning is one of the most common of metal cutting operations. In turning, a workpiece is rotated about its axis as single-point cutting tools are fed into it, shearing away excess material and creating the desired cylindrical surface. Turning can occur on both external and internal surfaces to produce an axially-symmetrical contoured part. Parts ranging from pocket watch components to large diameter marine propeller shafts can be turned on a lathe.Apart from turning, several other operations can also be performed on lathe.axially ['æksiəli] adv.轴向地symmetrical [si'metrikəl] a. 对称的cylindrical [si'lindrikl] a.圆柱形的contoured ['kɔntuəd] a.显示轮廓的，与某种形体轮廓相吻合的译文:在金属切削加工操作中，车削是最常见的一种。

专业英语翻译

1大多数的机加工主要是由五中基本的机床来完成Most of the mechanical operations are performed by five basic machine tools.2车床一般被成为整个机床加工设备家庭成员中之父。

The lathe is commonly called the father of the entire machine tool family.3.磨削加工是利用研磨颗粒来切学金属，磨削加工可分为精磨和非精磨。

Grinding makes use of abrasive particles to do the cutting.grinding may be classified as precisiom and nonprecision.ling can produce flat or angled surfaces,grooves,slots,gear teeth,and other profiles,depending on the shape of cutters being used.磨削可根据所用的铣刀形状分别加工平面，槽口，缝，轮齿及其他型面。

3.Nonprecision grinding involves the removal of metal where is not important.粗磨是指切除精度不高的工件多余的金属。

1A spherical mechanism is one in which each link has some point which remains stationary as the linkage moves and in which the stationary points of all links lie at a common location .在平面机构中，当连杆机构运动时，每一连杆都有某个保持静止的点，而且所有连杆的静止点都在同一位置上。

专业英语翻译

C. Manufacturing Cells (Group Technology)(Familyof Parts Concept)The use of manufacturing cells represents a particular kind of factory layout for manufacturing equipment. The essence of the concept is that, when manufacturing a particular part or family of similar parts in substantial quantities, the equipment for successive operations on the part should be grouped together. The operator - or team of operators who make that part (or the family of parts) - operate all the equipment in the cell. This arrangement is in contrast to a more traditional factory layout that groups like equipment together in departments. Then parts move from departmentto department for each operation. The advantage of the cell layout is that lines of communication and transportation are made very short. The factory's through-put rate is speeded; work-in-process inventory is greatly reduced; when problems arise at one operation, their effect on subsequent operations is immediately recognized. Route sheets to control movement of parts through the factory are greatly simplified or not needed. Operators learn what is needed at each operation to avoid problems at subsequent operations and have the satisfaction of seeing the results of their efforts.Quality tends to improve. The dis-advantage is that C.制造单元（成组技术）（零件族概念）制造单元的使用代表生产设备一种特殊的工厂布局方式。

大学英语专业翻译作业-词类转换

他总是喝很多酒。

He is a heavy drinker.他在讲话中特别强调提高产品质量。

In his speech, he emphasized on improving the quality of the products in particular.绝对不许违反这个原则。

Never allowed to violate this principle。

林则徐认为，要成功地禁止鸦片买卖，就得首先把鸦片焚毁了。

In Lin Zexu’s opinion, a successful ban of opium trade must be preceded by destruction.医生迅速到达，做了仔细检查，病人得以很快康复。

The doctor’s prompt arrival and careful examination of the patient brought his speedy recovery.一看到校门，我就想起了我的大学时代。

The sight of school gate reminds me of college life.获悉贵国遭受地震，我们极为关切。

We are deeply concerned at the news that your country has been struck by an earthquake.有人在背后支持他。

He got someone behind him.街中的一切逐渐消失在灰暗的暮色里。

Everything in the street was gradually disappeared into gray twilight.经过学校的门口，也改换了名称和模样，令我很生疏。

When I passed the school gate, that too had changed its name and appearance, making me feel quite a stranger.空气是这样的清香，使人感到分外凉爽、舒畅。

04南京邮电大学《专业英语》作业翻译

在fttab情况下光纤在远终端onu处结束因此通过dsl技术运用双绞线传输到用户其他情况根据从onu到用户的双绞线长度而变化在这个发展阶段没有允许操作者消除使用双绞线的实际方法但是由于通过铜线传输距离非常短dsl系统的高速版本也叫vdsl可以提供覆盖所有用户的带宽
专业英语作业
第一部分 :
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. Electrooptic amplitude modulation 电光幅度调制 Optoelectronics 光电子学 Transmission factor 传输因子 Phase modulation 相位调制 Resonant circuit 谐振电路 Transit-Time 迁移时间 Polarizer 起偏器 retardation bias 延迟偏移 Transverse electrooptic modulators 横向电光调制器 Traveling-wave modulators 行波调制器 Optical polarization 光偏振 Optical phase velocity 光学相速度 Crystal axis 晶轴 Modulated optical carrier 调制光载波 Frequency spectrum 频谱 Dielectric constant 介电常数 Threshold value 阈值 Index of refraction 折射率 Quantum-Well Laser 量子阱激光器 DC current-voltage characteristics 直流电流电压特性 Gain coefficient 增益系数 Optical data storage 光学数据存储 Propagation vector 传播矢量 Volume holograms 体积全息照相 Electrooptic crystal 电光晶体 Data-Bearing hologram 数据方位全息图 Object beam 物光 Reference beam 参考光 Incident beam 入射光 Diffracted beam 衍射光 Bragg diffraction 布拉格衍射 diffraction grating 衍射光栅 rate equations 速率方程 Coherence length 相干长度 Multi-hologram recording 多全息记录 Crosstalk 串扰 K space K 空间 Reconstruction 重构 Wavelength multiplexing 波长复用

英语翻译专业必翻经典文章英文原文+参考译文

文档简介文档简介一，一，英语翻译经典文章之英语翻译经典文章之英文原稿英文原稿二，二，中文翻译中文翻译：这篇英语文章的最好翻译版本！不是俺说的，是俺老师说哒！！英文原稿BrianIt seems my only request (It seems my only request (““please, let me sleep please, let me sleep””) is not clear enough, so I made this simple table that can help you when you that can help you when you’’re in doubt. Especially during the night Situa on what to do I’I’m sleeping m sleeping Do not enter my roomYou You’’re not sure if re not sure if I’I’I’m sleeping m sleeping and you want to checkNot your business Don Don’’t enter my room You You’’re under the re under the eﬀect eﬀect of drug of drugs s and you feel like entering my roomDon Don’’t enter my fucking room You saw a super cute video on you tu be and you want me to see it Don Don’’t enter my room Send me the link on FB World war 3 just started Don Don’’t care Don Don’’t enter my fucking room You or one of your friends want to want to ““have fun have fun”” with me I’I’m straight. m straight. m straight. I’I’I’m sorry m sorryDon't even touch my room door You want to clean my room Thanks but Thanks but I’I’I’ll take care of it myself ll take care of it myself Pu n just legalized gay marri agesThat That’’s wonderful! Finally !But don But don’’t enter my roomI’I’m not home m not homeDon Don’’t even think of entering my roomI’I’m m home, it it’’s day me, you knocked and I answered answered ““yes, come in yes, come in”” You can enter my room中文翻译中文翻译小子：小子：我只想好好地睡觉，你不明白吗？！所以，我做了这个简表。

2022年自考专业(英语)英语翻译考试真题及答案

2022年自考专业(英语)英语翻译考试真题及答案一、Word and Phrase Translation 20 points, 1 point each1、Christmas Eve2、marine resources3、bar counter4、market access5、fast-food restaurant6、brand image7、long-term debt8、research and development9、inherited privilege10、global economic governance11、教育部12、中国戏曲13、户外活动14、软着陆15、圣火16、语音识别技术17、电工产品18、领土争端19、横批20、机场摆渡车二、Translation Revision 20 points, 2 points each1、原文: Pollution is a live issue.译文：污染是个生活问题2、原文: Many Americans believe that competition is as important，or even more important, than democracy in preserving freedom. 译文: 很多美国人认为，竞争与民主同样重耍，在爱护自由方面孩至比民主还重要3、原文: The European Commission announced that a total of 15 EU states, plus Switzerland and Hong Kong, are now known to have received egg products contaminated by an insecticide. 译文：欧盟委员会宣布，现在共有15个欧盟国家以及瑞士和中国香港被知道进口了受杀虫剂污染的鸡蛋产品4、原文: But does this have anything to do with global warming, and are human emissions to blame译文：但这与全球气候变暖有关吗人类的碳排放该指责谁呢5、原文：It seems that wherever maples grow, there is a tradition to honor them. 译文：好像无论枫树生长在哪里，都有歌颂它的传统6、原文：确定有很多更为简洁、更为有效的方法去评定一个人的真实力量。

大学英语专业翻译作业

1)这种力，是一般人看不见的生命力，只要生命存在，这种力就要显现。

It is an invisible force of life. So long as there is life, the force will show itself2)凭窗站了一会，微微的觉得凉意侵入。

转过身来，忽然眼花缭乱，屋子里的别的东西，都隐在光云里；……Standing at the window for a while, I felt a bit chilly. As I turned round, my eyes suddenly dazzled before the bright light and could not see things distinctly. Everything in the room was blurred by a haze of light.3)这架收音机该有多大的重量啊！它载着解放区人民的心，载着全中国人民的希望，载着我们国家的命运。

What a heavy load this aero plane bore! It carried the hearts of people of the liberated areas, the hopes of the entire Chinese people, and the destiny of our country.4)看着信，林震不禁独自笑起来了，他拿起笔把“中于”改成“终于”，准备在回信时告诉他们下次要避免别字。

5)人无千日好，花无百日红。

Man cannot be alwaysfortunate; flowers do not last forever.（1）6)除了我这间房，大院里还有二十多间房呢。

一共住着多少家子，谁说得清？住两间房的就不多，又搭上今儿个搬来，明儿个又搬走。

我没那么好的记性。

大家见面，招呼声“吃了吗？”透着和气。

专业英语-2011年秋lecture7-学生翻译作业-含参考译文

This table on this slide presents...
3. Ending the Speech Text
1). Summarizing In conclusion,… In closing,…
参考译文：他对计算机的操作是陌生的。总的来说，甲烷系的烃惰性很强。碳原子的一个显著特征是它能够与其它碳原子共用电子。
Sodium（钠） is very active chemically.
Methane is less than half as heavy as water. The different hydrocarbons in crude （天然的） oil boil at different temperatures.
of my speech.
Getting back to the subject of the problem of theoretical considerations we can find that... I want to return to the first part of my presentation. 4). Introducing the Supporting Materials Let's go through the following points very rapidly.
Generally speaking, methane （甲烷） series are rather inert（惰性的）. One of the outstanding properties of carbon atoms is its ability to share its electrons with other carbon atoms.

化工专业英语作业翻译

专业英语课后作业翻译Lesson 4 Introdution Organic Chemistry(p59)有机化学简介Because of the tremendous number of organic compounds known, and of the many more being synthesized daily, the study of organic chemistry is not the study of individual compounds , it is the study of groups or families of compounds all closely related to each other. Obviously, the former approach would be prohibitive. Once the structural relationships of certain typical member of a particular group or family are understood, these structural features are understood for any one of the many members of the family even though some may not be known compounds, For each group of family of compounds often called homologous sreies of compounds, structureal features are improtant. In studying organic chemistry, it is not enough to know the identities of the elements and how many atoms of each element are present in a given molecule. More improtantly, the order in which these atoms are linked together to form the molecule must aslo be known, Once the identities of the element and the number of atoms prsent in each of these element have been established, structural studies are quite improtant. They require considerable effort and ingenuity on the part of the organic chemist.因为已知的有机化合物的数目庞大，而且还在逐日合成更多的品种，所以有机化学不是研究单个的化合物，而是把彼此密切相关的化合物按类或族来研究。

专业英语(上)课文翻译

1.一般工程钢（淬火和回火钢）经过简单正火处理后的碳素钢（碳含量0.25—0.60％，最大含Mn量1.0％），广泛应用于棒条、一般工程锻件、落垂锻件中。

对于给定的材料的最佳性质组合只体现在不超过一定尺寸的组件中，对于碳钢来说，这个尺寸很小（低限制的最大截面）。

这些碳素钢经过淬火和回火后可以获得优良的拉伸强度、屈服强度、延伸性和抗冲击性。

任何一种钢都有一个最小的冷却速度以产生有效硬化。

同样，热量被淬火介质吸收的速度也会受到最大截面的影响。

虽然有可能通过淬火来硬化特定钢材的小截面，但对于同一钢材的大截面，就不一定了。

这种质量效应和尺寸效应深深地影响着用于淬火和回火的钢的选择。

对于碳素钢来说，要达到满意的硬化效果，冷却速度必须很大，因此，能进行理想热处理的钢材，截面尺寸是有限制的。

而且，在金属中发生相变的参数是其均匀性质是不能赋予给超过一定厚度的工件，因为中心和截面表面之间出在不同的冷却速度。

更进一步说，具有高拉伸强度的普通钢，通常带有相对低的屈服点，并且延展性和韧性都低。

因此，普通碳素钢仅仅可能获得中等的拉伸强度水平与合理的延展性和韧度。

因此，想获得大尺寸和高的拉伸强度的要求，就需要用一种即使在低的淬火热吸收率下也能得到有效硬化的钢。

通过使用合金钢，这些难题便迎刃而解。

通过加入合金元素，如锰、镍、铬、钼、钒，降低了使钢有效硬化的最低冷却速度，这取决于添加元素的含量或元素的组合。

此外，组件的畸变和裂纹也减少了。

多种合金元素总和的应用比单一元素更为广泛。

这是由于有很多种元素同时存在的任一截面起的效果比起有等值的单一元素存在的截面起的效果要大。

此外，某些元素具有的缺点会抵消它们的优点，这就有必要限制它们在金属中的量。

我们也能发现，某些元素组合各自所具有的优点抵消各自的缺点，同时其他优点共同起作用。

铬的单一使用会使晶粒粗化，而镍在长时间加热时也能使含碳量高的钢产生碳化。

铬能够稳定碳化物的出现，而镍帮助晶粒优化。