无机非金属材料工程专业英语第1章ppt课件.ppt

Chapter1 Introduction,Learning Objectives 21.1 Historical Perspective 21.2 Materials Science and Engineering 21.3 Why Study Materials Science and Engineering? 41.4 Classification of Materials 51.5 Advanced Materials 61.6 Modern Materials Needs 6,汉语翻译成英文,材料科学材料工程金属材料非金属材料陶瓷材料高分子材料复合材料生物材料半导体材料先进材料,Words and phrases,Deep-seated: close/intimate 紧密的Virtually: practically/in fact/nearly/as good as/in effect/in essence实际上地Every segment of our everyday lives:日常生活的每个方面Segment: section/division/part/piece部分、片 Manipulate: control/employ控制、使用,Designate: define/denote/label/ name 标记、命名Access to): approach 途径Pottery: pots/dishes or other items made from clay and fired in a kiln (oven) 陶器Alter: change 改变Utilization: application /use 应用、 用途Empower: control 驾驭、控制,Words and phrases,Characteristic: peculiarity, feature/trait/attribute/property特质Evolve: produce 生产Complex: sophisticated 复杂的Contemporary：Someone who lived or was in a particular place at the same time as someone else. Modern/belonging to the present time 同时代的Nebulous: vague. An idea that is nebulous is not at all clear or exact. 模棱两可的,Related to: be concerned with 相关的Encompass：to completely cover or surround sth.覆盖或环绕Realm：territroy/monarchy/ zone/domain/region /kingdom/area/branch 区域Agglomerate：melt 团聚、成块-volcanic rock consisting of large fragments fused together,Vocabulary,Contemporary 当代Stimulus 激励，刺激Opaque 不透明 Translucent 半透明Transparent 透明Deep-seated 根深蒂固的，深层的Existence 存在, 实在, 生活, 存在物, 实在物Sophisticated 复杂的Forerunner 先驱(者), 传令官, 预兆Intimately 密切地,Elaboration 解释，阐述Stepwise楼梯式的, 逐步的Recreation 消遣, 娱乐segment段, 节, 片断Deteriorative 恶化，变质，,Evoke 引起，唤起Interdisciplinary 交叉学科Metallurgy 冶金Nebulous 模糊的，云雾状的Agglomerate 团聚，大块Dielectric current 介电常数Thermal conductivity 热传导,Heat capacity 热容Refraction 折射，衍射Ductility 延展性Overriding 最重要的Prohibitive 抑制Judicious 明智的criterion 准则,1.1 Historical perspective (观察，透视),Materials are probably more deep-seated (根深蒂固的, 深层的) in our culture than most of us realize. Transportation, housing, clothing, communication, recreation（娱乐）, and food productionvirtually（事实上） every segment （方面）of our everyday lives is influenced to one degree or another（不同程度地） by materials.,Historically, the development and advancement of societies have been intimately（密切地） tied to the members ability to produce and manipulate （使用）materials to fill their needs. In fact, early civilizations have been designated（命名） by the level of their materials development (i.e., Stone Age, Bronze Age, Iron Age).,Stone age,iron age,Steel age,Advanced materials age,bronze age,The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay（粘土）, skins, and so on. With time they discovered techniques for producing materials that had properties superior to those of the natural ones; these new materials included pottery （陶器） and various metals.,Furthermore, it was discovered that the properties of a material could be altered （改变）by heat treatments and by the addition of other substances. At this point, materials utilization（利用） was totally a selection process, that is, deciding from a given, rather limited set of materials the one that was best suited for an application by virtue of （凭借）its characteristics（特性）.,It was not until relatively recent times that scientist came to understand the relationship between structural elements of materials and their properties. This knowledge, acquired in the past 60 years or so, has empowered （使能够） them to fashion(shape ), to a large degree（非常）, the characteristics of materials.,Thus, tens of thousands of different materials have evolved （出现）with rather specialized characteristics that meet the needs of our modern and complex society. These include metals, plastics, glasses, and fibers.,The ugly bowl and the beautiful cup are different in appearance, but do you know the bowl is the ancestor of the cup if trace back to 7000 years ago?,porcelain,ceramics,The development of many technologies that make our existence so comfortable has been intimately associated with the accessibility (途径) of suitable materials. An advancement in the understanding of a material type is often the forerunner（先驱） to the stepwise （逐步的） progression of a technology.,For example, automobiles would not have been possible without the availability （利用）of inexpensive steel or some other comparable substitute. In our contemporary (同时代的) era, sophisticated （复杂的）electronic devices rely on components that are made from what are called semi-conducting （半导体的） materials.,Materials scientists and engineers seek （try, investigate寻求）to understand and control the basic structure of materials in order to make the products stronger, lighter, brighter, safer, faster and better suited (adapt, fit )to (适合) human needs. Every part in your car and every piece of your computer are carefully selected to optimize (优化) performance and cost effectiveness.,3.Task for Materials scientists and engineers,4.Materials Science and Engineering (MSE) discipline The discipline of materials science involves investigating the relationships that exist between the structures and properties of materials. In contrast, materials engineering is, on the basis of these structureproperty correlations, designing or engineering the structure of a material to produce a predetermined (预定的) set of properties. Throughout this text we draw attention to the relationships between material properties and structural elements.,Structure is at this point a nebulous（模糊的） term that deserves some explanation. In brief, the structure of a material usually relates to the arrangement of its internal components. Subatomic structure involves electrons within the individual atoms and interactions with their nuclei(原子核). On an atomic level, structure encompasses (包含) the organization of atoms or molecules relative to one another.,The next larger structural realm (区域), which contains large groups of atoms that are normally agglomerated (团聚) together, is termed microscopic, meaning that which is subject to direct observation using some type of microscope. Finally, structural elements that may be viewed with the naked eye are termed macroscopic.,The notion of property deserves elaboration. While in service use, all materials are exposed to external stimuli （刺激） that evoke（唤起） some type of response. For example, a specimen subjected to forces will experience deformation; or a polished metal surface will reflect light. Property is a material trait（特性） in terms of the kind and magnitude of response to a specific imposed （施加的）stimulus （刺激）. Generally, definitions of properties are made independent of （与无关）material shape and size.,Virtually all important properties of solid materials may be grouped into six different categories: mechanical, electrical, thermal, magnetic, optical, and deteriorative. For each there is a characteristic type of stimulus capable of provoking (evoke) different responses. Mechanical properties relate deformation to an applied load or force; examples include elastic modulus (弹性模量) and strength.,For electrical properties, such as electrical conductivity （电导率）and dielectric constant（介电场数）, the stimulus is an electric field（电场）.The thermal（热的） behavior of solids can be represented in terms of heat capacity （热容） and thermal conductivity（热导率）.,Magnetic（磁性的） properties demonstrate the response of a material to the application of a magnetic field （磁场）.For optical（光学的） properties, the stimulus is electromagnetic （电磁的）or light radiation（光辐射）; index of refraction（折射） and reflectivity （反射）are representative optical properties. Finally, deteriorative（腐败的） characteristics indicate the chemical reactivity（化学反应） of materials. The chapters that follow discuss properties that fall within each of these six classifications.,In addition to structure and properties, two other important components are involved in the science and engineering of materials, viz (namely, that is). processing (加工) and performance（性能）. With regard to the relationships of these four components, the structure of a material will depend on how it is processed. Furthermore, a materials performance will be a function of its properties. Thus, the interrelationship between processing, structure, properties, and performance is linear, as depicted in the schematic illustration shown in Figure 1.1.,Throughout this text we draw attention to the relationships among these four components in terms of the design, production, and utilization of materials.Materials Science and Engineering (MSE) is the discipline(学科) devoted to (专心于) helping human beings use materials more effectively(有力的) and efficiently (有效的). The story of materials is an ancient one that began with humanity learning to shape（成形） rock and work metal. From the prehistoric beginning, the story of human advances in materials continues to unfold (展开).,For example, the development of steels permitted the building of skyscrapers and suspension bridges; advances in silicon based technology provided the foundation for electronics and computers,New biomaterials have resulted in medical breakthroughs that save and improve lives. Materials scientists and engineers focus on the manipulation of atomic scale structure to change materials properties,This focus has pushed our discipline to the forefront（最前沿） of developing and applying new tools to observe and manipulate matter at the smallest scales. These advances continue to play an important part in the emergence of fields such as nanotechnology at the beginning of the 21st century.,5 The future of humanity depends on our wise use of materialsMost of the technological innovations that we associate with contemporary（现代） life have involved some major advance in materials processing or application.,Automobiles, satellites, televisions, computers and DVD players all would not be possible without advances in polymers, ceramics, metals and semiconductors. New advances are being pioneered in our laboratories.,The direct threat of global warming and dwindling(缩小)fossil fuel resources have made the efficient use of energy a priority(优先). MSE faculty and students work actively to make light-weight engine components out of aluminum and magnesium in order to boost(促进,增强) fuel efficiency. They also pioneer improved high-temperature materials that are important for efficient jet engines and electricity generation.,To restore hearing to deaf people and sight to blind people prosthetic devices must make contact between the brain and a microphone or camera. MSE faculty and students work to find ways to Interface（ 界面）silicon technology to neural tissue（神经组织）. This requires the development of coatings that are biocompatible (生物相容的) and electrically conducting.,Moores law states that the number of transistors（晶体管） on the latest computer chip doubles approximately every 18 months. This translates into more memory and faster, cheaper computers. But there is a limit to the density of transistors that can be placed on a computer chip using current technology.,MSE faculty and students develop methods to spontaneously（自发）generate structures a few tens to hundreds of atoms across to form the basis for quantum （量子）computers. These next generation computers will exploit the physics of quantum confinement （量子陷阱） that dominate at that tiny scale.,Making components out of new materials often involves an extensive cycle of design, creation, testing and redesign. This process is costly and time consuming. MSE faculty and students develop computer simulation techniques to predict material behavior such as resistance to failure, stability, and high temperature formability. These computing advances speed the way toward the introduction of new materials in a safe and cost-effective manner.,Building on a solid foundation and bridging many fields,Course work in the MSE department emphasizes the relationship between how a material is processed, its structure and the resulting properties and is built on a firm grounding in physics and chemistry. Hands-on learning and access to sophisticated instrumentation allow students to gain valuable experience in characterizing materials structure and properties.（you can be a police using SEM or TEM）,Because materials enable new products and technologies, it is nearly impossible to find an engineering discipline that does not interface in some way with Materials Science and Engineering. This is especially true for mechanical, aerospace, electrical, chemical and biomedical engineering where dual majors are often pursued.,1.2 Materials science and engineering1. Terms of definition Materials Science: investigating the relationships that exist between the structures and properties of materials.,Materials Engineering: on the basis of structure property correlations, designing or engineering the structure of a material to produce a predetermined set of properties.,Structure: A nebulous(模糊） term; In brief, the arrangement of its internal componentsSubatomic structure-involves electrons within the individual atoms and interactions with their nucleiAt atomic level-structure encompasses the organization of atoms or molecules relative to one another.,microscopic (显微)a large group of atoms agglomerated together.Macroscopic (宏观) where the structure elements might be viewed by naked eye.,roperty: 1.a material trait (特性) in terms of the kind and magnitude of response to a specific imposed stimulus。Examples:A loaded steel bar will be deformedA heated plastic plate will be softened A polished metal surface will reflect light,1.Mechanical2.electrical 3.thermal 4. Magnetic5.optical 6.deteriorative(变质，化学),a elastic modulusb. index of refractionc. strengthd. reflectivitye. thermal conductivityf. heat capacityg. electrical conductivityh. plasticityI. electromagneticj. light radiationchemical reactivityDielectric constant,Virtually all important properties of solid materials may be grouped into six different property:,In addition to structure and properties, processing and performance are another two important components for MSE. Four components that are involved in the design, production and utilization of materialsprocessing structure properties performance,Three thin aluminum disk specimens placed over printed matter, from left to right they are transparent, translucent and opaque, why? Because they are processed differently , then have different structure; different structure leads to different properties and if they are put into use, the performance must be different too.,1.3 Why study Materials science and engineering? Many an applied scientist or engineer will at one time or another，whether mechanical, civil (土木), chemical, or electrical, be exposed to a design problem involving materials. Examples might include a transmission gear (传动齿轮), the superstructure for a building, an oil refinery (炼油厂) component, or an integrated circuit chip (集成电路板). Of course, materials scientists and engineers are such specialist who are totally involved in the investigation and desig