材料科学与工程专业学习英语.docx

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1、编号：时间：2021 年 x 月 x 日书山有路勤为径，学海无涯苦作舟书山有路勤为径，学海无涯苦作舟页码：第1页 共38页第 1 页 共 38 页材料科学与工程专业英语材料科学与工程专业英语Unit1Unit1 MaterialsMaterials ScienceScience andand MetallurgicalMetallurgicalEngineeringEngineeringMaterials are properly more deep-seated in our culture than most of us realize.Trans-portation,housing,cl

2、othing,communication,recreation and food production-virtuallyevery segment of our everyday lives is influenced to one degree or another by materials.Historically,the development and advancement of societies have been intimately tied tothe members abilities to produce and manipulate materials to fill

3、 their needs.In fact,early civilizationshave been designated by the level of their materials development(i.e.Stone Age,Bronze Age).The earliest humans has access to only a very limited number of materials,those thatoccur naturally stone,wood,clay,skins,and so on.With time they discovered techniquesf

4、or producing materials that had properties superior to those of the natural ones:thesenew materials included pottery and various metals.Furthermore,it was discovered that theproperties of a material could be altered by heat treatments and by the addition of othersubstances.At this point,materials ut

5、ilization was totally a selection process,that is,deciding from a given,rather limited set of materials the one that was best suited foran application by virtue of its characteristic.It was not until relatively recent timesthat scientists came to understand the relationships between the structural e

6、lements ofmaterials and their properties.This knowledge,acquired in the past 60 years or so,hasempowered them to fashion,to a large degree,the characteristics of materials.Thus,tensof thousands of different materials have evolved with rather specialized characteristicsthat meet the needs of our mode

7、rn and complex society.The development of many technologies that make our existence so comfortable has beenintimately associated with the accessibility of suitable materials.Advancement in theunder-standing of a material type is often the forerunner to the stepwise progression ofa technology.For exa

8、mple,automobiles would not have been possible without the availabilityof inexpensive steel of some other comparable substitutes.In our contemporary era,sophisticated electronic devices rely on components that are made from what are calledsemiconducting materials.MaterialsMaterials ScienceScience Eng

9、ineeringEngineeringMaterials science is an interdisciplinary study that combines chemistry,physics,metallurgy,engineering and very recently life sciences.One aspect of materials scienceinvolves studying and designing materials to make them useful and reliable in the serviceof humankind.It strives fo

10、r basic understanding of how structures and processes on theatomic scale result in the properties and functions familiar at the engineering level.Materials scientists are interested in physical and chemical phenomena acting across largemagnitudes of space and time scales.In this regard it differs fr

11、om physics of chemistrywhere the emphasis is more on explaining the properties of pure substances.In materialsscience there is also an emphasis on developing and using knowledge to understand how theproperties of materials can be controllably designed by varying the compositions,structures,and the w

12、ay in which the bulk and surfaces phase materials are processed.In contrast,materials engineering is,on the basis of those structure propertiescorrelations,designing or engineering the structure of a material to produce a编号：时间：2021 年 x 月 x 日书山有路勤为径，学海无涯苦作舟书山有路勤为径，学海无涯苦作舟页码：第2页 共38页第 2 页 共 38 页predet

13、ermined set of properties.In other words,materials engineering mainly deals withthe use of materials in design and how materials are manufactured.Structure is a nebulous term that deserves some explanation.In brief,the structureof a material usually relates to the arrangement of its internal compone

14、nts.Subatomicstructure involves electrons within the individual atoms and interactions with their nuclei.On an atomic level,structure encompasses the organization of atoms or molecules relativeto one another.The next large structural realm,which contains large groups of atoms thatare normally agglom

15、erated together,is termed microscopic meaning that which is subjectto direct observation using some type of microscope.Finally,structural elements that maybe viewed with the naked eye are termed macroscopic.The notion of property deserves elaboration.While in service use,all materials areexposed to

16、external stimuli that evoke some type of response.For example,a specimen subjectto forces will experience deformation;or a polished metal surface will reflect light.Property is a material trait in terms of the kind and magnitude of response to a specificimposed stimulus.Generally,definitions of prop

17、erties are made independent of materialshape and size.Virtually all important properties of solid materials may be grouped into six differentcategories;mechanical,electrical,thermal,magnetic,optical,and deteriorative.Foreach there is s characteristic type of stimulus capable of provoking different r

18、esponses.Mechanical properties relate deformation to an applied load or force:examples includeelastic modulus and strength.For electrical properties,such as electrical conductivityand dielectric constant,the stimulus is an electric filed.The thermal behavior of solidscan be represented in terms of h

19、eat capacity and thermal conductivity.Magnetic propertiesdemonstrate the response of a material to the application of a magnetic field.For opticalproperties,the stimulus is electromagnetic or light radiation:index of refraction andreflectivity are representative optical properties.Finally,deteriorat

20、ivecharacteristics indicate the chemical reactivity of materials.In addition to structure and properties,two other important components are involved inthe science and engineering of materials,namely processing and performance.Withregard to the relationships of these four components,the structure of

21、a material will dependon how it is processed.Furthermore,a materials performance will be a function of itsproperties.Thus,the interrelationship between processing,structure,properties,andperformance is linear as follows:ProcessingStructurePropertiesPerformanceWhyWhy StudyStudy MaterialsMaterials Sci

22、enceScience andand Engineering?Engineering?Why do we study materials?Many an applied scientists or engineers,whether mechanical,civil,chemical,or electrical,will be exposed to a design problem involving materialsat one time or another.Examples might include a transmission gear,the superstructure for

23、a building,an oil refinery component,or an integrated circuit chip.Of course,materialsscientists and engineers are specialists who are totally involved in the investigation anddesign of materials.Many times,a materials problem is to select the right material from many thousandsavailable ones.There a

24、re several criteria on which the final decision is normally based.First of all,the in-service conditions must be characterized.On only rare occasion doesa material possess the maximum or ideal combination of properties.Thus,it may be necessaryto trade off one characteristic for another.The classic e

25、xample involves strength andductility;normally,a material having a high strength will have only a limited ductility.编号：时间：2021 年 x 月 x 日书山有路勤为径，学海无涯苦作舟书山有路勤为径，学海无涯苦作舟页码：第3页 共38页第 3 页 共 38 页In such cases a reasonable compromise between two or more properties may be necessary.A second selection consid

26、eration is any deterioration of material properties that mayoccur during service operation.For example,significant reductions in mechanical strengthmay result from exposure to elevated temperatures or corrosive environments.Finally,probably the overriding consideration is economics.What will the fin

27、ishedproduct cost?A material may be found that has the ideal set of properties,but isprohibitively expensive.Here again,some compromise is inevitable.The cost of a finishedpiece also includes any expense incurred during fabrication.The more familiar an engineer or scientist is with the various chara

28、cteristics andstructure-property relationships,as well as processing techniques of materials,the moreproficient and confident he or she will be to make judicious materials choices based onthese criteria.(Selected from Materials Science and Engineering:AnIntroduction,by William D Callister,2002)NewNe

29、w WordsWords andand ExpressionsExpressionspotteryn.陶瓷by virtue of依靠（力量），凭借，由于，因为empowervt.授权，准许，使能够empower sb.to do sth.授权某人做某事forerunnern.先驱（者），传令官，预兆stepwisea.逐步地，分阶段地interdisciplinarya.交叉学科的metallurgyn.冶金学nebulousa.星云的，云雾状的，模糊的，朦胧的agglomeraten.大团，大块；a.成块的，凝聚的elaborationn.详尽的细节，解释，阐述electrical con

30、ductivity电导性，电导率dielectric constant介电常数thermal conductivity热导性，热导率heat capacity热容refractionn.衍射reflectivityn.反射ductilityn.延展性corrosivea.腐蚀的，蚀坏的，腐蚀性的；n.腐蚀物，腐蚀剂overridinga.最重要的；高于一切的prohibitivea.禁止的，抵制的judiciousa.明智的criterionn.标准，准则，尺度NotesNotes1.It was not until relatively recent times that scientist

31、s came to understand therelationships between the structural elements of materials and their properties.这是一个强调句，强调时间。came to+不定式，译为“终于”，“开始”。参考译文：直到最近，科学家才终于了解材料的结构要素与其特性之间的关系。编号：时间：2021 年 x 月 x 日书山有路勤为径，学海无涯苦作舟书山有路勤为径，学海无涯苦作舟页码：第4页 共38页第 4 页 共 38 页2.The notion of propertydeserves elaboration.deserv

32、e,应受，值得；elaboration,详尽阐述。参考译文：“property一词的概念值得详细阐述。3.Many an applied scientist or engineer,.,will at one time or another be exposed toa design problem involving materials.many a(an,another)+单数名词，许多的，多的，一个接一个的，例如：many a person,许多人。be exposed to,暴露，面临，处于境地。参考译文：许多应用科学家或工程师，在某个时候都将面临着涉及材料的设计问题。4.On onl

33、y rare occasion does a material possess the maximum or ideal combination ofproperties.这是一个倒装强调句，其原句为：A material possesses the maximum or idealcombination of properties on only rare occasion.句中的possess是“具有”的意思。ExercisesExercises1.Question for discussion(1)What is materials science?What is materials e

34、ngineering?(2)Why do we study materials science and engineering?(3)Give the important properties of solid materials.2.Translate the following into Chinesematerials scienceStone Agenaked eyeBronze ageoptical propertyintegrated circuitmechanical strengththermal conductivity.Materials science is an int

35、erdisciplinary study that combines chemistry,physics,metallurgy,engineering and very recently life sciences.One aspect of materials scienceinvolves studying and designing materials to make them useful and reliable in the serviceof human kind.Virtually all important properties of solid materials may

36、be grouped into six differentcategories:mechanical,electrical,thermal,magnetic,optical,and deteriorative.In addition to structure and properties,two other important components are involvedin the science and engineering of materials,namely processing and performance.The more familiar an engineer or s

37、cientist is with the various characteristics andstructure-property relationships,as well as processing techniques of materials,the moreproficient and confident he or she will be to make judicious materials choices based onthese criteria.3.Translate the following into English交叉学科介电常数固体材料热容力学性质电磁辐射材料加

38、工弹性系数（模数）U Unitnit 2 2 ClassificationClassification ofof MaterialsMaterialsBasicBasic ClassificationsClassifications andand EngineeringEngineering MaterialsMaterialsSolid materials have been conveniently grouped into three basic classifications:metals,ceramics and polymers.This scheme is based prima

39、rily on chemical makeup and atomic编号：时间：2021 年 x 月 x 日书山有路勤为径，学海无涯苦作舟书山有路勤为径，学海无涯苦作舟页码：第5页 共38页第 5 页 共 38 页structure,and most materials fall into one distinct grouping or another,although thereare some intermediates.In addition,there are three other groups of important engineeringmaterials-composite

40、s,semiconductor,and biomaterials.Composites consist of combinationsof two or more different materials,whereas semiconductors are utilized because of theirunusual electrical characteristics;biomaterials are implanted into the human body.A briefexplanation of the material types and representative char

41、acteristics is offered next.MetalsMetals:Metallic materials are normally combinations of metallic elements,they havelarge numbers of nonlocalized electrons;that is,these electrons are not bound toparticular atoms.Many properties of metals are directly attributable to these electrons.Metals are extre

42、mely good conductors of electricity and heat,and are not transparent tovisible light;a polished metal surface has a lustrous appearance.Furthermore,metals arequite strong,yet deformable,which accounts for their extensive use in structuralapplications.Ceramics:Ceramics:Ceramics are compounds between

43、metallic and nonmetallic elements:they aremost frequently oxides,nitrides,and carbides.The wide range of materials that fallswithin this classification includes ceramics that are composed of clay minerals,cement,and glass.These materials are typically insulative to the passage of electricity and hea

44、t,and are more resistant to high temperatures and harsh environments than metals and polymers.With regard to mechanical behavior,ceramics are hard but very brittle.Polymers:Polymers:Polymers include the familiar plastic and rubber materials.Many of them areorganic compounds that are chemically based

45、 on carbon,hydrogen,and other nonmetallicelements;furthermore,they have very large molecular structures.These materials typicallyhave low densities and may be extremely flexible.Composites:Composites:A number of composite materials have been engineered that consist of morethan one material type.Fibe

46、rglass is a familiar example,in which glass fibers are embeddedwithin a polymeric material.A composite is designed to display a combination of the bestcharacteristics of each of the component materials.Fiberglass acquires strength from theglass and flexibility from the polymer.Many of the recent mat

47、erial developments haveinvolved composite materials.Semiconductors:Semiconductors:Semiconductors have electrical properties that are intermediatebetween the electrical conductors and insulators.Furthermore,the electricalcharacteristics of these materials are extremely sensitive to the presence of mi

48、nuteconcentrations of impurity atoms,which concentrations may be controlled over very smallspatial regions.The semiconductors have made possible the advent of integrated circuitrythat has totally revolutionized the electronics and computer industries over the past twodecades.Biomaterials:Biomaterial

49、s:Biomaterials are employed in components implanted into the human bodyfor replacement of diseased or damaged body parts.These materials must not produce toxicsubstances and must be compatible with body tissue(i.e.must not cause adverse biologicalreactions).All of the above materials-metals,ceramics

50、,polymers,composites andsemiconductors-may be used as biomaterials.For example,some of the biomaterials such asCF/C(carbon fibers/carbon)and CF/PS(polysulfone)are utilized in artificial hipreplacements.AdvancedAdvanced MaterialsMaterialsMaterials that are utilized in high-technology(or high-tech)app