1材料概论 材料科学概论课件 双语.ppt
November 2011Introduction to Materials材料学院材料概论Introduction to MaterialsContent Definition材料的定义材料的定义Types材料的类型材料的类型Structure材料的结构材料的结构 Structure properties processing 结构性能工艺之间的关系结构性能工艺之间的关系Chapter 1 Introduction to Materials1.1 Materials and Material Science材料的发展史,就是人类社会的发展史。材料的发展史,就是人类社会的发展史。石器时代陶器时代青铜器时代铁器时代材料的重要性材料的重要性无机非金属材料无机非金属材料复合材料复合材料高分子材料高分子材料金属材料金属材料木材木材皮革皮革纤维纤维纸纸青铜青铜铁铁钢钢金金皮胶皮胶橡胶橡胶赛璐珞赛璐珞陶陶玻璃玻璃水泥水泥火石火石合金钢合金钢耐热合金耐热合金先进功能陶瓷先进功能陶瓷各种基体复合材料各种基体复合材料功能高分子功能高分子高温高分子高温高分子高强高模高分子高强高模高分子通用高分子通用高分子韧性工程陶瓷韧性工程陶瓷金属陶瓷金属陶瓷耐火材料耐火材料时间时间/年年相相对对占占有有量量玻璃态金属玻璃态金属5000公元前公元前0公元公元1000 150018001900194019601980199020002010纤维增强塑料纤维增强塑料稻草杆砖稻草杆砖微合金钢微合金钢骨骨瓷瓷材料的发展历史材料的发展历史()石器时代:()石器时代:旧石器时代原始人采用天然的石、木、竹、骨等材料作旧石器时代原始人采用天然的石、木、竹、骨等材料作为狩猎工具;为狩猎工具;新石器时代公元前新石器时代公元前6000年,人类发明了火,掌握了钻木年,人类发明了火,掌握了钻木取火技术,用以烧制陶瓷。瓷器的出现已成为中华民族文化的取火技术,用以烧制陶瓷。瓷器的出现已成为中华民族文化的象征之一,对世界文化产生过深远的影响。象征之一,对世界文化产生过深远的影响。原始人打造的石器原始人打造的石器印地安人用的石斧印地安人用的石斧()青铜器时代:这是人类社会出现()青铜器时代:这是人类社会出现最早的金属材料,中国历史上曾有过灿最早的金属材料,中国历史上曾有过灿烂的青铜文化。烂的青铜文化。青铜鼎青铜鼎青铜宝剑青铜宝剑青铜编钟青铜编钟(chimes)(3)铁器时代:用铁作为材料来制造农具,铁在农)铁器时代:用铁作为材料来制造农具,铁在农业上的广泛应用,推动了以农业为中心的科学技业上的广泛应用,推动了以农业为中心的科学技术日益进步;以钢铁为中心的金属材料大规模发术日益进步;以钢铁为中心的金属材料大规模发展,有力地摧毁了封建社会的生产方式,萌发了展,有力地摧毁了封建社会的生产方式,萌发了资本主义。资本主义。hoe铁斧铁斧铁梨铁梨plow (4)聚合物时代)聚合物时代 二战后各国致力于恢复经济,发展工农业生产,对材二战后各国致力于恢复经济,发展工农业生产,对材料提出了质量轻、强度高、价格低等一系列要求。具有优料提出了质量轻、强度高、价格低等一系列要求。具有优良性能的工程塑料部分地代替了金属材料。合成高分子材良性能的工程塑料部分地代替了金属材料。合成高分子材料的问世是材料发展的重大突破,从此以金属材料、陶瓷料的问世是材料发展的重大突破,从此以金属材料、陶瓷材料、高分子材料为主体,建立了完整的材料体系,形成材料、高分子材料为主体,建立了完整的材料体系,形成了材料科学。了材料科学。Polymeric Biomaterials人工心脏:聚酯、聚氨酯、环氧树脂人工肺:硅橡胶半透膜关节(肩、髋、膝):聚四氟乙烯人工肾(kidney):透析膜Atrifical Heart聚醚型聚氨酯聚酯编织管环氧树脂聚酯硅油Artifical BoneResomer Resorbable Polyester:Polylactide,Polyglycolide or the copolymersBoehringer Ingelheim KG1.1 Materials and Material Science 影响材料使用的因素影响材料使用的因素 materials behavior availability cost synthesis and production method processing techniques environmental acceptability 1.1.1 DefinitionConstitute:The materials making up the surrounding world consist of discrete particles,having a submicroscopic size.组成组成:构成物质世界的材料由具有亚微观尺度的各种微粒子组成。1.1 Materials and Material ScienceMaterials:defined as solids used by man to produce items which constitute the support for his living environment.Character:materials have certain compositions;can be formed;with certain shape and color;can be used and reused or recycled.特点特点:具有一定的成分和配比;可成型加工;保持一定形状和外观;具有使用价值并可回收再利用。可成型加工可成型加工保持一定形状和外观保持一定形状和外观具有使用价值具有使用价值Essential role of materials:indispensable to our society as food,energy and information.substance material:differences 战机舰船导弹火箭人造卫星战车高速列车汽车高层建筑1.1.2 Classificationl Basis of classification:atomic structures nature of chemical bonds:金属键 Metallic bond离子键 Ionic bond共价键 Covalent bond次价键 secondary bond 范德华力 Van der Waals bond 氢 键 Hydrogen bondl Classification:metals and their alloys:-metallic bondingl Classification:organic polymers-covalent bonding&secondary bondingl Classification:ceramics-ionic bonding&covalent bondingTypes of materials Metals and their alloys:are good conductors of heat and electricity;are opaque to visible light;are hard,rigid;can undergo plastic deformation have a high melting temperature(Tm).Organic polymers:made up of long-chain molecules;are electrical and thermal insulators;are light and easily formable;and the best-known organic polymers are:poly(vinyl chloride)(PVC);polyethylene(PE);polystyrene(PS).Ceramics/inorganic nonmetallic materials:the combination of metallic elements(Mg,Al,Ti,.)with non-metallic elements(o);have high mechanical and thermal resistance at high temperature;are very hard and used as abrasives;are electrical and thermal insulators;but some are thermal conductors,or semiconductors.Composite materials:are constituted by two or more different materials,have specific properties.glass fiber reinforced resins:lightweight composites with high mechanical strengthconcrete:an agglomeration of cement,sand and gravel1.1.3 Propertiesl Mechanical properties:the behavior of materials deformed by a set of forces.弹性 Elasticity 塑性 Plasticity 强度 Strength 硬度 Hardness 韧性 Toughness 疲劳特性 Fatigue behaviour 耐磨性 Abrasion resistance Physical properties:the behavior of materials subjected to the action of temperature,electric or magnetic fields,or light.电性能 Electric properties 磁性能 Magnetic properties 热性能 Thermal properties 光性能 Optical properties Chemical properties:the behavior of material in a reactive environment.抗腐蚀能力 Corrosion resistance:atmospherically,chemically(salts,sour,alkali)1.1.4 Use of materialsFactors related to the use of a material are:l Quality:properties and functionsl Economy:costs related to materials,processing and energyl Environment:environmental behavior of the materiall Resources&Recycling:resources and possible recycling1.1.5 Materials Sciencel Materials Science:to establish the relation between composition,atomic or molecular organization,the microstructure and the macroscopic properties of materials.Materials Science studies:化学组成化学组成、化学键化学键、合成方法合成方法:chemical composition,chemical bonds and synthesis methods 特性特性:nature of materials 结构与性能的关系结构与性能的关系:describe the relationship between structure and properties based on crystal physics and solid physics材料科学材料科学:基于现代科学技术,一方面,利用化学手段研究材料的化学成分、化学键和合成方法;另一方面,借助物理学方法,研究材料性质,主要根据晶体物理和固体物理描述材料结构和性能的关系。The four basic aspects of materials science and technology Materials Engineering:concerned with manufacturing,transformation and shaping processes.Research Fields 研究领域研究领域MaterialsScienceScientificAspectsTechnicalAspectsSubstance SynthesisPhenomena DescriptionNature&PropertiesPreparation/FabricationProperties DeterminationsApplicationsForms of solids:crystalline&amorphous 1.3 Structural Characteristic of Materialsdifference:crystalline state of solid more stable than amorphous state 1.3 Structural Characteristic of MaterialsCrystalline:an ordered arrangement of the elementary particles(ions,atoms or molecules).晶体结构晶体结构:晶体中原子(或离子)在空间规则排列的方式。Properties of crystalsDepend on:the electronic structure of atoms the nature of the interactions in the crystalthe spatial arrangement of elementary particles,and the composition,size and shape of crystals.1.3.1 Crystal Lattice 晶格晶格 Arrangement of elementary particles in a crystal(a):three-dimensional view (b):schemeMorphology of PbS crystal with NaCl structure假设假设:(1)elementary particles(ions,atoms or molecules)are spheres;(2)In a simpler model,spheres are replaced by points 晶格晶格(lattice):假想的格架 晶胞晶胞 an elementary cell:the smallest of parallelepipeds晶体、晶格和晶胞示意图晶体、晶格和晶胞示意图 (a)(a)晶体晶体(b)(b)晶格晶格 (c)(c)晶胞晶胞 An elementary cell:described by three sections a,b,and c,and three angles made by each two of these sections,and.晶格常数晶格常数 lattice constant/lattice spacings:晶胞的三条棱边长 a、b、c.Types of elementary cell:simple three-dimensional lattice body-centred cell face centred cell Coordination number:determines the quantity of the nearest equidistant elementary particles.配位数配位数:晶格中与任一原子处于相等 距离并相距最近的原子数目。配位数配位数:-body-centred cubic(BCC)lattice:for each atom is eight(C8)-simple cubic lattice(SC):six(C6)-face-centred cubic(FCC)lattice:12(C12)金属三种典型晶格配位数示意图金属三种典型晶格配位数示意图体心立方晶胞体心立方晶胞 配位数配位数8 8面心立方晶胞面心立方晶胞 配位数配位数1212密排六方晶胞密排六方晶胞 配位数配位数1212Packing factor(Packing factor(填充因子填充因子):The packing factor is determined as the ratio of the volume of all elementary particles per elementary cell to the total volume of the elementary cell.Packing factor(Packing factor(填充因子填充因子):Octahedral(a)and tetrahedral(b)voids in FCC lattice metalsPacking factor(Packing factor(填充因子填充因子):Close packing of atoms in crystal ABAABCAPacking mode 1(ABCABC)Packing mode 2(ABCABC)Packing mode 3(AaBbCcAaBbCc)1.3.2 Crystallographic Indicescoordinate:同等的、并列的(pl.)坐标origin of coordinates 坐标原点Indices:index的复数形式Reciprocal:互惠的,相应的,倒数的,彼此相反的 n.倒数,互相起作用的事物Parenthese:圆括号,插入语,插曲slip plane:滑移面,滑动面,滑面,侧滑面Prism:棱柱 Term:1.3.2 Crystallographic IndicesHCP crystalsABAcGraphite1.3.2 Crystallographic IndicesCrystallographic indices of(a):directions(b):planesAnisotropy:The properties of crystals are different in various crystallographic directions,which are associated with an ordered arrangement of atoms (ions,molecules)in space.This phenomenon is called anisotropy.1.3.3 AnisotropyVirtually all properties of crystals are anisotropic.The phenomenon is however more pronounced in crystals with structures of a poor symmetry.Natural crystalline solids are mostly polycrystals,i.e.they consist of a plurality of differently oriented fine crystals and exhibit no anisotropy,since the mean statistic spacings between atoms are essentially the same in all directions.Anisotropy:The properties of crystals are different in various crystallographic directions,which are associated with an ordered arrangement of atoms(ions,molecules)in space.This phenomenon is called anisotropy.1.3.3 AnisotropyVirtually all properties of crystals are anisotropic.The phenomenon is however more pronounced in crystals with structures of a poor symmetry.Natural crystalline solids are mostly polycrystals,i.e.they consist of a plurality of differently oriented fine crystals and exhibit no anisotropy,since the mean statistic spacings between atoms are essentially the same in all directions.