• / 72
  • 下载费用:10 金币  

武汉理工大学材料概论课件1-1.ppt

关 键 词:
武汉理工大学材料概论课件1-1.ppt
资源描述:
November 2011,Introduction to Materials,材料学院,《材料概论》 Introduction to Materials,Content-Definition 材料的定义-Types 材料的类型-Structure 材料的结构– Structure – properties – processing结构-性能-工艺之间的关系,Chapter 1 Introduction to Materials,1 Materials and Material Science,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,,,,,,,,,,,,,,,,,,,,,无机非金属材料,复合材料,高分子材料,金属材料,木材 皮革 纤维,纸,青铜,铁,钢,金,皮胶,橡胶,赛璐珞,陶,玻璃,水泥,火石,合金钢,耐热合金,先进功能陶瓷,各种基体复合材料,功能高分子,高温高分子,高强高模高分子,通用高分子,韧性工程陶瓷,金属陶瓷,耐火材料,时间 / 年,相对占有量,玻璃态金属,5000 公元前,0 公元,1000,1500,1800,1900,1940,1960,1980,1990,2000,2010,,纤维增强塑料,稻草杆砖,微合金钢,,,骨,,瓷,材料的发展历史,(1)石器时代:旧石器时代--原始人采用天然的石、木、竹、骨等材料作为狩猎工具;新石器时代--公元前6000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,印地安人用的石斧,(2)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烂的青铜文化。,青铜鼎,青铜宝剑,青铜编钟(chimes),(3)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,萌发了资本主义。,hoe,铁斧,铁梨plow,,(4)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,Artifical Bone,Resomer® Resorbable Polyester:Polylactide, Polyglycolide or the copolymers —Boehringer Ingelheim KG,,,1 Materials and Material Science,影响材料使用的因素,materials behavior,availability,cost,synthesis and production method,processing techniques,environmental acceptability,1.1.1 Definition Constitute: The materials making up the surrounding world consist of discrete particles, having a submicroscopic size. 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 Materials and Material Science,Materials: 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; withcertain shape and color; can beused and reused or recycled. 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,保持一定形状和外观,具有使用价值,Essential role of materials:indispensable to our society as food, energy and information. substance ~ material: differences,材料的应用领域,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 ClassificationBasis 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 bond,Classification:metals and their alloys: - metallic bonding,Classification:organic polymers - covalent bonding & secondary bonding,Classification: ceramics - ionic bonding & covalent bonding,Types of materials,Metals and their alloys:are good conductors of heat and electricity;are opaque to visible light;are hard, rigid;can undergo plastic deformationhave a high melting temperature (Tm).,Organic polymers: made up of long-chain molecules;are electrical and thermal insulators;are light and easily formable; andthe 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; butsome 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 strength concrete:an agglomeration of cement, sandand gravel,1.1.3 PropertiesMechanical 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, electricor 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:Quality:properties and functionsEconomy:costs related to materials, processing and energyEnvironment:environmental behavior of the materialResources & Recycling:resources and possible recycling,1.1.5 Materials ScienceMaterials Science:to establish the relation betweencomposition, atomic or molecularorganization, the microstructure and the macroscopic properties ofmaterials.,Materials Science studies:化学组成、化学键、合成方法:chemical composition, chemical bonds and synthesis methods特性: nature of materials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: 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,Materials Science,Scientific Aspects,Technical Aspects,Substance Synthesis,Phenomena Description,Nature & Properties,Preparation / Fabrication,Properties Determinations,Applications,Forms of solids: crystalline & amorphous,1.3 Structural Characteristic of Materials,difference: crystalline state of solid more stable than amorphous state,1.3 Structural Characteristic of Materials,Crystalline: an ordered arrangement of the elementary particles (ions, atoms or molecules). 晶体结构: 晶体中原子(或离子)在空间规则排列的方式。,Properties of crystals Depend on: the electronic structure of atoms the nature of the interactions in the crystal the spatial arrangement of elementary particles, and the composition, size and shape of crystals.,1.3.1 Crystal Lattice 晶格,Arrangement of elementary particles in a crystal (a): three-dimensional view (b): scheme,,Morphology of PbS crystal with NaCl structure,假设: (1) elementary particles (ions, atoms or molecules) are spheres;(2) In a simpler model, spheres are replaced by points晶格 (lattice):假想的格架晶胞 an elementary cell: the smallest of parallelepipeds,,晶体、晶格和晶胞示意图,晶体,(b)晶格,(c)晶胞,An elementary cell: described by three sections a, b, and c, and three angles made by each two of these sections, α, β, and γ. 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 latticebody-centred cell face centred cell,,Coordination number: determines the quantity of the nearest equidistant elementary particles. 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:- 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,体心立方晶胞配位数8,面心立方晶胞配位数12,密排六方晶胞配位数12,,Packing factor(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(填充因子):,,Octahedral (a)and tetrahedral (b) voids in FCC lattice metals,Packing factor(填充因子):,,,Close packing of atoms in crystal,ABA,ABCA,ATOMIC PACKING,Packing mode 1 (ABCABC…),,Packing mode 2 (ABCABC…),,Packing mode 3 (AaBbCcAaBbCc…),1.3.2 Crystallographic Indices,coordinate: 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 Indices,HCP crystals,1.3.2 Crystallographic Indices,Crystallographic indices of (a): directions (b): planes,,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 Anisotropy,Virtually 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 Anisotropy,Virtually 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.,
展开阅读全文
  微传网所有资源均是用户自行上传分享,仅供网友学习交流,未经上传用户书面授权,请勿作他用。
0条评论

还可以输入200字符

暂无评论,赶快抢占沙发吧。

关于本文
本文标题:武汉理工大学材料概论课件1-1.ppt
链接地址:https://www.weizhuannet.com/p-10071176.html
微传网是一个办公文档、学习资料下载的在线文档分享平台!

网站资源均来自网络,如有侵权,请联系客服删除!

 网站客服QQ:80879498  会员QQ群:727456886

copyright@ 2018-2028 微传网络工作室版权所有

     经营许可证编号:冀ICP备18006529号-1 ,公安局备案号:13028102000124

收起
展开