材料导论 课程 第一讲 材料概论

材料导论Instructor：蔡艳ycai@March 4 4, 2010前言材料是人类赖以生存和发展的物质基础。

Material is the basis of human civilization and social development. 20世纪70年代人们把信息 材料和能源誉为当代文明的三大支柱 20世纪70年代人们把信息、材料和能源誉为当代文明的三大支柱。

Information, Material and Energy are three mainstays in modern civilization since 1970. 80年代以高技术群为代表的新技术革命把新材料技术、信息技术和生物技术并 列为新技术革命的重要标志。

With information technology and biotechnology, new material is listed as the marks k of f th the N New T Technological h l i lR Revolution. l ti2超纯硅、砷化镓研制成功，导致大规模和超大规模集成电路的诞生， 使 计算机运算速度从每秒几十万次提高到现在的每秒百亿次以上； 计算机运算速度从每秒几十万次提高到现在的每秒百亿次以上 航空发动机材料的工作温度每提高100℃，推力可增大24％； 隐身材料能吸收电磁波或降低武器装备的红外辐射，使敌方探测系统 难以发现。

难以发现雷达隐身 材料可见光隐 身材料红外隐身 材料3课程目标To know basic knowledge regarding Materials Science and Engineering. 了解材料科学与工程的基本概念与知识 To develop p interest of Material Science and Engineering. g g 培养对材料科学与工程的兴趣和热爱 To cultivate capability to study further professional English papers in material fields fields. 具备阅读材料专业英语论文的初步能力 To be confident in group cooperation, presenting and other social actives. 提高团队合作、英语演讲等社会活动素质4教学大纲| | | | | | | | | |材料科学的定义和研究范畴 Definition f and research range of f material science 材料发展史上的重要里程碑 Greatest milestones in history 材料的分类以及对生活和文明的影响 Classification and its effect on human society 材料制备和加工手段、表征工具 Methodologies g of fabricating g materials 学科交叉及发展前景 I t di i li Interdisciplinary development d l t and d prospects t5参考书籍1. R. W. Cahn, “The Coming of Materials Science”, 2001. , Jr., , “Materials Science and Engineering: g g An introduction”, , 2. W. D. Callister, Wiley, 7th Ed., 2006. 3. P. A. Thrower, “Materials in Today’s World”, 3rd Ed., 2008/wiki/Materials_science26https:///matse081/starthere/l1.html课程安排ScheduleEvaluation7in life eWhy computers become cheaper while its performance better?1906年：发明电子管，出现了无线电技术、电视机和电子计算机； 1948年：发明半导体晶体管 电子设备的小型化 轻量化 性能提高； 1948年：发明半导体晶体管，电子设备的小型化、轻量化，性能提高； 1958年：集成电路出现，电子设备发展飞跃，硅半导体材料迅速发展； 20世纪90年代：集成电路加工技术达0.3μm，存储器价格下降； ……9What are differences between metals and ceramics ?Metals Crystal structure Large number of free electrons Metallic bond Good electric conductivity Opaque Uniform atoms High tensile strength Low shear strength Good ductility Plastic flow high Impact strength Relative high g weight g Moderate hardness Ceramics Crystal structure Captive electrons Ionic / covalent bond Poor conductivity Transparent(in thin sections) Different-size atoms Poor tensile strength High shear strength Poor ductility (brittle) None Poor impact strength Relative low weight g Extreme hardness10聚合物与塑料Repeated chemical unitsCarbon atom Tetrahedron h d (pyramid) ( d)Monomer5~500 atomsP l Polymer> 50 monomersCells g growing g on p polymer y → artificial tissues11光纤Glass fibers —— telecommunication, composites Carbon fibers —— reinforcement Metallic fibers Polymer fibers —— composites, textiles Natural fibers12材料的多样性金属与合金 Metals and alloys 金属与合金，Metals 金属与合金， 陶瓷，Ceramics 陶瓷， Ceramics 复合材料，Composites 复合材料， Composites 聚合物与塑料 Polymers 聚合物与塑料，Polymers 聚合物与塑料， P l and d plastics l ti 光纤，Fibers 光纤， Fibers 碳，Carbon 碳， Carbon 生物材料，Biomaterials 生物材料， Biomaterials …1314A Shape Memory Alloy (SMA, memory alloy, muscle wire, smart alloy，形状记忆合金) is an alloy that "remembers" its original, cold, forged shape, and which returns to that shape after being deformed by applying heat. ft b i d f db l i h t This material is a lightweight, solid-state alternative to conventional actuators such as 水压的 气压的 hydraulic（水压的）, pneumatic（气压的）, and motor-based systems. Shape memory alloys have applications in industries including medical and aerospace. The difference between the heating transition and the cooling transition give rise to the shape of the curve depends on the material properties of the shape memory alloy, such as the alloying and work hardening.15气凝胶（Aerogels 气凝胶（ Aerogels） ）通常是指以纳米量级超微颗粒相互聚集构成纳米多孔网络结构，并在 网络孔隙中充满气态分散介质的轻质纳米固态材料。

Aerogel is a manufactured material with the lowest bulk density （体积密度） of any known porous solid. It is derived from a gel in which the liquid component of the gel has b been replaced l d with ith a gas. Th The result lt i is an extremely t l l low-density d it solid lid with ith several l remarkable properties, most notably its effectiveness as a thermal insulator and its extremely low density.A demonstration of aerogel's insulation propertiesA 2.5 kg g brick is supported pp by yap piece of aerogel weighing only 2 grams16Light Amplification by Stimulated Emission of Radiationmirror 2excitation it ti Optical Resonator Active environment excitationmirror 1Laser beam17Bei M in Material t i lS Science i & Engineering E i i f from now on! !MSE = Material Science and Engineering工程材料（Engineering material）指那些具有专门设计的结构、专 门的性能 专门用于某 领域的材料 门的性能、专门用于某一领域的材料。