1、Unit One Lesson1 Tool Materials,教学目标及要求1.掌握课文中有关工具钢方面的专业词汇和专业术语；2.结合工具钢的相关专业知识阅读课文，提高翻译能力。 重点1.工具钢的专业词汇和专业术语；2.翻译课文：工具材料种类词汇；金属材料的物理、力学性能词汇。 难句分析及翻译的基础知识Part（） 翻译的基础知识简介一、什么是翻译？,教学思路设计时间分配（共100min）：1.讲解课文中的专业词汇和术语； 2.讲解课后生词、大声朗读； 3.翻译课文，注意穿插相关专业知识； 4.分析难点句型，讲解翻译的基础知识； 5.学生答疑。,Contents,Background Kno
2、wledge New Words and Phrased Questions Glossary of Terms Text Analysis Language Points & Translating Techniques Reading Materials Summary References,工具钢 工具钢是用以制造切削刀具、量具、模具和耐磨工具的钢种。工具钢具有较高的硬度和在高温下能保持高硬度、红硬性，以及高的耐磨性和适当的韧性。 工具钢一般分为碳素工具钢、合金工具钢和高速工具钢三种。carbon tool steels Tool steels alloy tool steels hig
3、h speed tool steels,Background Knowledge,New Words and Expressions,Terms：1. Metal： 金属iron 铁 steel 钢aluminum 铝magnesium 镁zinc 锌bismuth 铋copper 铜lead 铅,2. Non-metal： 非金属wood 木材plastics 塑料rubber 橡胶ceramics 陶瓷材料diamond 金刚石epoxy resin 环氧树脂,New Words and Expressions,3. Characateristics：性能/特性strength 强度har
4、dness 硬度toughness 韧性brittleness 脆性plasticity 塑性/可塑性ductility 可锻性malleability 可延压性,New Words and Expressions,elasticity 弹性 wear resistance 耐磨性 dimensional stability 尺寸稳定性 thermal conductivity 导热性 electrical conductivity 导电性 rate of thermal expansion 热膨胀率 melting point 熔点 moldulus of elasticity 弹性模量,T
5、ext,The Three Major Categories of Tool Materials: Ferrous tool materials have iron as a base metal and include tool steel, alloy steel, carbon steel, and cast iron. Nonferrous materials have a base metal other than iron and include aluminum, magnesium, zinc, lead, bismuth, copper, and a variety of a
6、lloys. Nonmetallic materials are those materials such as woods, plastics, rubbers, epoxy resins, ceramics, and diamonds that do not have a metallic base.,Text,Physical And Mechanical Properties of a Material: Physical properties are those properties which are natural in the material and cannot be pe
7、rmanently altered without changing the material itself. Include: weight, color, thermal and electrical conductivity, rate of thermal expansion, and melting point. The mechanical properties of a material are those properties which can be permanently altered by thermal or mechanical treatment. Include
8、: strength, hardness, wear resistance, toughness, brittleness, plasticity, ductility, malleability, and modulus of elasticity.,力学性能,物理性能,Questions,What is meant by the term“physical properties of a material”? What are the mechanical properties of a material What makes a material either ferrous or no
9、nferrous? What are some applications of tool steels?,Glossary of Terms,1carbide tool 硬质合金刀具 2alloy tool steel 合金工具钢 3alloy cast iron 合金铸铁 4carbon steel 碳素钢 5carbon tool steel 碳素工具钢 6cast iron 铸铁 7cast steel 铸钢 8die block steel 模具钢 9die material 模具材料 10free cutting steel 易切削钢,11high alloy steel 高合金钢
10、12high carbon steel 高碳钢 13low alloy steel 低合金钢 14low carbon steel 低碳钢 15shock resistant tool steel 抗冲击工具钢 16cold work tool（die）steel 冷作工具（模具）钢 17hot work tool（die）steel 热作工具（模具）钢 18nodular graphite iron 球墨铸铁 19malleable cast iron 可锻铸铁 20mottled cast iron 麻口铸铁,Reading Materials,Carbon SteelsCarbon st
11、eels are used extensively in tool construction. Carbon steels are those steels which only contain iron and carbon, and small amounts of other alloying elements. Carbon steels are the most common and least expensive type of steel used for tools.,Carbon Steels,The three principal types of carbon steel
12、s used for tooling are low carbon, medium carbon, and high carbon steels. Low carbon steel contains carbon between 0.05% and 0.3%. Medium carbon steel contains carbon between 0.3% and 0.7%. And high carbon steel contains carbon between 0.7% and 1.5%. As the carbon content is increased in carbon stee
13、l, the strength, toughness, and hardness are also increased when the metal is heat treated.,Low carbon steels are soft, tough steels that are easily machined and welded. Due to their low carbon content, these steels cannot be hardened except by case hardening. Low carbon steels are well suited for t
14、he following applications: tool bodies, handles, die shoes, and similar situations where strength and wear resistance are not required. Medium carbon steels are used where greater strength and toughness is required. Since medium carbon steels have a higher carbon content, they can be heat treated to
15、 make parts such as studs, pins, axles, and nuts. Steels in this group are more expensive as well as more difficult to machine and weld than low carbon steels.,High carbon steels are the most hardenable type of carbon steel and are used frequently for parts where wear resistance is an important fact
16、or. Other applications where high carbon steels are well suited include drill bushings, locators, and wear pads. Since the carbon content of these steels is so high, parts made from high carbon steel are normally difficult to machine and weld.,Alloy Steels,Alloy steels are basically carbon steels wi
17、th additional elements added to alter the characteristics and bring about a predictable change in the mechanical properties of the alloyed metal. Alloy steels are not normally used for most tools due to their increased cost, but some have been found favor for special applications. The alloying eleme
18、nts used most often in steels are manganese, nickel, molybdenum and chromium. Another type of alloy steel frequently used for tooling applications is stainless steel. Stainless steel is a term used to describe high chromium and nickelchromium steels. These steels are used for tools which must resist
19、 high temperatures and corrosive atmospheres.,Die Steels,The die material is relevant directly to the die life as well as die cost. Recently, the commonly used die steel for cold blanking is as follows: The carbon tool steel T8A, T10A, T12A are the cheapest and the most widely used. Its hardness aft
20、er annealing is lower than that of the alloy steel. It has good machining property, and the process of forging, annealing and quenching is easy to be mastered. It is suitable to manufacture the working parts of the blanking die with small size and simple shape. But its hardenability and abrasionresi
21、stant are bad, its quench distortion is large and its working life is short.,The low alloy tool steel, such as CrWMn, 9CrSi, 9Mn2V etc, can be quenched by oil, therefore it has a good hardenability and a small quench distortion. Comparing with T10A, 9Mn2V has a higher hardness and abrasionresistance
22、, and also has a good machining property.,Materials for manufacturing the die parts and their best heat treatment rules,Language Points & Translating Techniques,Example 1:To properly select a tool material, there are several physical and mechanical properties you should understand to determine how t
23、he materials you select will affect the function and operation of the tool.为了选择工具材料，你应当掌握材料的一些物理性能和力学性能，以便确定所选材料对工具的功能和操作会有何影响。不定式to properly select a tool material 放在句首用作目的状语；you select 为定语从句修饰前面的the materials。,Example 2:A great effort is made to keep porosity, segregation, impurities, and nonmetal
24、lic inclusions to as low a level as possible.(对于工具钢的冶炼)，要最大限度地降低钢中的气孔、偏析、杂质以及非金属夹杂物的含量。这里的a great effort is made是make a great effort 的被动形式，意为“尽一切努力或尽量“。在科技英语中表示主语为”人们“的时候，一般使用被动结构或者用one做主语的主动句。,Example 3 :From a composition standpoint , tool steels are carbon alloy steels which are capable of being
25、hardened and tempered (从化学组成来说，工具钢是能够被淬硬并能经过回火变韧的碳素合金钢。）这里限定性定语从句which are capable of being hardened and tempered修饰先行词carbon alloy steels 。and连接两个并列的一般式动名词被动结构，做of的宾语， capable of being hardened and tempered做主语补足语。）,Part（） 翻译的基础知识简介 一、什么是翻译 翻译是各个不同民族之间进行沟通和交流的工具。翻译本身是一种语言活动，是利用一种语言把另一种语言所表达的内容重新表达出来。
26、翻译与创作不同，翻译者不能任意地表达自己的思想，他只能准确而完整地传达原作的思想内容。 然而各民族之间由于文化背景的不同，生活习惯的差异，在语言的表达上也必然存在着千差万别。各有其特点，各有其规律。翻译即是通过不同语言的特点、规律的对比，找出相应的表达手段。,Example 4 :,试看下面的例子： Lathe sizes range from very little lathes with the length of the bed in several inches to very large ones turning a work many feet in length. 车床有大有小，
27、小的床身只有几英寸长，大的能车削许多英尺长的工件。 我们把原文与译文对比，就会看到原文是一个较长的简单句，而译文却是三个短的单句。之所以有这样的差异，是因为英语在表达复杂概念时，习惯使用长句，而汉语则很少使用长句，一般都分成几个短句，层次分明，言简意赅。 从这个例句不难看出，翻译决不是简单地或原封不动地照搬原文的表达形式，而是有意识地选择与原文作用相等的语言手段来表达原意。从这个意义上讲，翻译是一种创造性的语言活动，是一种艺术。,Summary,掌握必须的专业单词（New Words） 掌握常用的专业术语（Glossary of Terms) 掌握基本的语法知识 掌握基本的翻译技巧,Refer
28、ences,References,1.Donald R.Askeland Pradeep P. Phule.Essentials of Materials Science and Engineering M.Nelson, a division of Thomson Learning.2004 2. William.F.Smith. Structure and Properties of Engineering Alloys M. New York. McGraw-Hill Book Company. 1987 3. E.Paul De Garmo, J Temple.Black and Ronald A. Kohser. Materials and Processes in Manufacturing (Sixth Edition)M. New York. Macmillan Publishing Company. 1984 4. http:/ 5. http:/,
