完整教學課件材料科學與工程基礎

1、Fundamentals of Materials Science and EngineeringDepartment of Material ScienceWang YanObjective Introduce fundamental concepts in Material Science and EngineeringItems to be learned: material structure how structure dictates properties how processing can change structurePotential applications: Use

2、materials properly Realize new design opportunities with materials目錄第四章 材料的性能 (Material Properties)第三章 材料組成和結構 (Compositions and Structures of Materials )第二章 物質結構基礎 (Structure of Matter)第一章 緒論 (Introduction)第五章 材料的制備和成型加工 (Preparation and Manufacturing of Materials)1.1 Defination and Historical Pers

3、pective1.2 Classification of Materials 1.3 Materials Science and Engineering1.4Why Study Materials Science and Engineering1.5 Modern Materials Needs第一章緒 論Chapter 1 Introduction1.1Definition of Materials and Historical Perspective DefinitionThe matter (substance)，not spiritlyWebster “New Internationa

4、l Dictionary（1971）”:The substance or matter of which anything is made or may be made. Webster編者“New International Dictionary（1971年）”中關于材料（Materials）的定義為：材料是指用來制造某些有形物體（如：機械、工具、建材、織物等的整體或部分）的基本物質（如金屬、木料、塑料、纖維等） 邁爾新百科全書中材料的含義：材料是從原材料中取得的，為生產半成品、工件、部件和成品的初始物料，如金屬、石塊、木料、皮革、塑料、紙、天然纖維和化學纖維等等。Materials and

5、 Raw Materials(原材料) Raw Materials: any crude, unfinished, not to obtain products，but produce materials。（having chemical changes）Materials：to obtain products.原料一般不是為獲得產品，而是生產材料， 往往伴隨化學變化。 材料的特點往往是為獲得產品，一般從材料 到產品的轉變過程不發(fā)生化學變化。1.1Definition of MaterialsDefinitionMaterials and matter： Materials can be ma

6、de of one kind of or more kinds of matters. The same matter can get different types or using materials because of different processing methods. 材料可由一種或多種物質組成。 同一物質由于制備方法或加工方法不同可以得到用途各異、類型不同的材料。Material：材料科學 （工科） 物質科學 （理科） 材料是指具有滿足指定工作條件下使用要求的形態(tài)和物理性狀的物質。1.1Definition of Materials and Historical Persp

7、ective Historical Perspective 材料是人類社會發(fā)展的巨大推動力，制造生產工具的物質基礎是材料。石器 陶 器銅 器 編 鐘鐵 器 陶瓷藝術品結束動畫圖片陶瓷藝術結束動畫圖片玻璃瓶結束動畫圖片水果籃結束動畫圖片門窗玻璃結束動畫圖片搪瓷茶壺結束動畫圖片天然花崗巖結束動畫圖片景泰藍工藝 藍地虎頭魚缸結束動畫圖片中國古代陶器秦始皇兵馬俑結束動畫圖片琉 璃 瓦結束動畫圖片結束動畫圖片二、一些典型的高聚物材料塑料布結束動畫圖片塑料薄膜結束動畫圖片塑料模仁結束動畫圖片特種工程塑料結束動畫圖片特種高聚物材料結束動畫圖片合成纖維結束動畫圖片一些典型的高聚物材料聚丙稀短纖維結束動畫圖片合

8、成橡膠輪胎結束動畫圖片衣服 纖維結束動畫圖片塑料的應用塑 鋼 窗三、聚合物的應用結束動畫圖片塑料的應用結束動畫圖片塑料的應用結束動畫圖片塑料的應用結束動畫圖片不銹鋼餐具結束動畫圖片Golf stick結束動畫圖片破粉碎設備結束動畫圖片地鐵列車結束動畫圖片吸音吊頂結束動畫圖片電力陶瓷結束動畫圖片砂輪結束動畫圖片鋼 塔結束動畫圖片結束動畫圖片汽車與高速公路結束動畫圖片大江截流結束動畫圖片汽車工業(yè)結束動畫圖片結束動畫圖片飛機結束動畫圖片火箭發(fā)射結束動畫圖片 陶瓷藝術品結束動畫圖片Today The history of materials is the history of human societ

9、y and science technologyThe development of process： Simple Complex Single property Comprehensive property Structural materials Functional materials Single material Composite materials 綜合性能結構材料功能材料復合材料1.2 Classification of MaterialsBasicmetals.ceramics. polymers.Engineering materialsCompositesSemicon

10、ductorbiomaterialsMaterialsChemical Makeup State Use Application Field MetalInorganic Nonmetal Material PolymerCompositesGaseous LiquidSolidFunctional StructuralArchitectural、Packagingp5Advanced materialsConcept: Materials that are utilized in high-technology applications. By high technology we mean

11、 a device or product that operates or functions using relatively intricate and sophisticated principles ; examples include electronic equipment, computers, fiber-optic systems, spacecraft, aircraft, and military rocketry.1.3 Materials Science and EngineeringMaterials Science ： involves investigating

12、 the relationships that exist between the structures and properties of materials (研究結構與性能之間的關系)Materials Engineering: designing or engineering the structure of a material to produce a predetermined set of properties, based on these structure-property correlations.(設計材料 結構以產生預定的性能)p2Structure (結構)Con

13、cept：relates to the arrangement of its internal components （內部成分的組織排列）Subatomic On an atomic levelp3Property (性能)Notion： a material trait in terms of the kind and magnitude of response to a specific imposed stimulus. (一種材料對外界刺激反應的類型和程度)Category: mechanical (機械性), electrical（電性）, thermal（熱性）, magneti

14、c（磁性）, optical（光學性）, and deteriorative（失效性）p3Mechanical PropertiesNotion: relate deformation to an applied load or force; examples include elastic modulus and strength.Plot of elastic modulus versus temperature for tungsten (鎢) , steel (鋼), and aluminum (鋁)Electrical PropertiesConcept: the stimulus

15、is an electric field, such as electrical conductivity (電導率) and dielectric constant (介電常數(shù)).The electrical resistivity versus temperature for copper and three copper-nickel alloys, one of which has been deformed.Note: Electrical conductivity is the reciprocal of the resistivityThermal PropertiesThe t

16、hermal behavior of solids can be represented in terms of heat capacity (熱容) and thermal conductivity (導熱系數(shù)).Thermal conductivity versus composition for copper-zinc alloys.Magnetic PropertiesDemonstrate the response of a material to the application of a magnetic field.Schematic magnetization curves f

17、or soft and hard magnetic materials.Optical PropertiesThe stimulus is electromagnetic or light radiation; index of refraction (折射) and reflectivity (反射) are representative optical properties.Photograph showing the light transmittance of three aluminum oxide specimens. From left to right: single-crys

18、tal material (sapphire), which is transparent (透明); a polycrystalline and full dense (nonporous) material, which is translucent (半透明) and a polycrystalline material the contains approximately 5% porosity, which is opaque(不透明).Deteriorative CharacteristicIndicate the chemical reactivity of materials.

19、Processing (加工) and Performance (表現(xiàn)性能) The structure of a material will depend on how it is processed.A materials performance will be a function of its properties.Materials Science and Engineering Logic1.4 Why Study Materials Science and EngineeringA material problem: One of selecting the right mate

20、rial from the many thousands that are available.Three criteria on which the final decision is normally based: 1. the in-service conditions must be characterized, for these will dictate the properties required of the material.(性能)2. any deterioration of material properties that may occur during servi

21、ce operation.（使用環(huán)境）3. economics.（經濟）The Materials Selection Process1.5 Modern MaterialsNeeds (self-study) In spite of the tremendous progress that has been made in the discipline of materials science and engineering within the past few years, there still remain technological challenges, including th

22、e development of even more sophisticated and specialized materials, as well as consideration of the environmental impact of materials production. Materials for use in nuclear energy.New high-strength, low-density structural materials, as well as materials with higher-temperature capabilities, for us

23、e in transportation vehicles.Materials for use in the developments that find new, economical sources of energy, and employ the present resources more efficiently.Materials for use in pollution control techniques.The nonrenewable resources, such as polymer and some metals, are gradually becoming depl

24、eted, which necessitates: (1) the discovery of additional reserves, (2) the development of new materials having comparable properties with less adverse environment impact (3) Increase recycling efforts and the development of new recycling technologiesSummaryCourse Goals: Use the right material for t

25、he job. Understand the relation between properties, structure, and processing. Recognize new design opportunities offered by materials selection.Ch.2 Structures of Materials （材料的結構）Content2.1 Introduction (簡介)2.2 Fundamental Concepts (基本概念)2.3 Unit cells (單胞)2.4 Metallic crystal Structures (金屬的晶體結構)

26、2.5 Density Computations- Metals (金屬的密度計算)2.6 Ceramic Crystal Structures (陶瓷的晶體結構)2.7 Density Computations-Ceramics (陶瓷的密度計算)2.8 Silicate Ceramics(硅酸鹽陶瓷）2.9 Polymer Structures(聚合物結構)Ch.2 Structures of Materials （材料的結構） The most concerned about materials for people are their properties. The propertie

27、s of materials are related to their composition (成分)、 crystal structures (晶體結構) and the processing (加工).2.1 Introduction (簡介)Ch.2 Structures of Materials （材料的結構）Ch.2 Structures of Materials （材料的結構）Eg：Mg (hexagonal close-packed, 六方密堆結構) brittle fewer slip planeAu (face-centered cubic，面心立方結構) ductile

28、more slip planeNoncrystalline (otically transparent 透明) Crystalline (Opaque 不透明, or Translucent 半透明)Ch.2 Structures of Materials （材料的結構）Crystal Structure The different properties between same classification of materials are caused by their Atomic arrangement in the solid state.the manner in which at

29、oms, ions, or molecules are spatially arranged.the manner in which atoms, ions, or molecules are spatially arranged.p31Crystal Structures(晶體結構)2.2 Fundamental Concepts (基本概念) Crystal (晶體) It is solid. The arrangement of atoms in the crystal is periodic. In crystalline structure, the atoms display bo

30、th short-range and long-range order. Eg: metals, many ceramics, and even some polymers.晶 體：原子(團)沿三維空間呈周期性長程有序 (long range order)排列的固體物質（金屬，大多陶瓷及一些聚合物） 非晶體：原子(團)無周期性長程有序排列的物質 （包括氣體，液體和部分固體） 晶體的性質 熔點確定 有自發(fā)形成規(guī)則多面體外形的能力 穩(wěn)定性 （晶體能量最低） 各向異性（物理性質不同） 均勻性（周期小，宏觀連續(xù)）Crystal Structures(晶體結構) Lattice（點陣,晶格） An in

31、finite array of points in space, in which each point has identical surroundings to all others. A three dimensional array of points coinciding with atom positions (or atomic sphere center).p32點陣： 晶體結構的微觀特征 某種結構單元（基元）在三維空間作周期性規(guī)則排列基元：原子、分子、離子或原子團 (組成、位形、取向均同)Crystal Structures(晶體結構)Crystal Structures(晶

32、體結構) Crystal Structure（晶體結構） It can be described by associating each lattice point with a group of atoms. 抽象為 基元 幾何點 抽象為基元的三維空間周期排列 空間點陣 晶體結構空間點陣結構基元(原子,分子或集團) 點陣反映晶體結構的平移對稱 點陣是抽象的幾何圖形 點陣中每個陣點的周圍環(huán)境均相同Crystal Structures(晶體結構)2.3 Unit cells (晶胞) The smallest component of the crystal, which when stacke

33、d together with pure translational repetition reproduces the whole crystal. The basic structure unit of the crystal structure and defines the structure by virtue of its geometry and the atom positions within. 晶胞：代表晶體內部結構的基本重復單位（平行六面體） 晶胞的基本要素： A大小和形狀 B各原子坐標位置Crystal Structures(晶體結構) Lattice Dimensio

34、ns (晶格參數(shù)) a, b and c are the unit cell edge lengths. , , and , are the angles. between b and c between c and a between a and bp49按晶格常數(shù)的不同組合可將晶胞分為7種類型，對應7個晶系 (Crystal system)DeterminationX-ray diffraction transmission electron microscope Crystal Structures(晶體結構)2.4 Metallic crystal Structures (金屬的晶體結

35、構)Three crystal structures are found in most metals: Face-centered cubic (面心立方); Body-centered cubic (體心立方);Hexagonal-close-packed (六方密堆).p33金屬鍵； 無方向性；原子呈圓球狀密堆積Metallic crystal Structures (金屬的晶體結構) Face-centered cubic (FCC) crystal structure (面心立方結構) FCC crystal structure has a unit cell of cubic ge

36、ometry, with atoms located at each of the corners and centers of all the cube face.除8個頂點外，每個面心上有一個陣點. a=b=c, =90oCu, Al, Au, Agp33Metallic crystal Structures (金屬的晶體結構)Metallic crystal Structures (金屬的晶體結構) The relationship between cube edge length a and the atomic radius R : Corner and face positions

37、 are really equivalent (頂角和面心的位置是完全相等的) For FCC structure, a total of four atoms are assigned to a given unit cell (對FCC結構來說,每個單胞有4個完整的原子)81/ 8（角）+ 61/ 2（面）p33Metallic crystal Structures (金屬的晶體結構)The length of a face diagonal 4R,The cell edge length aFor FCC, it is a cube. So, there has a right tria

38、ngle on the face:a2+a2=(4R)2Unit cell volume of FCC VC is:Solution: aa4RRMetallic crystal Structures (金屬的晶體結構) Coordination number (配位數(shù)) For each atom, coordination number is the number of nearest-neighbor or touching atoms.The face atom , has four corner nearest-neighbor , four face atoms from behi

39、nd , and other four equivalent face atoms from the front.Coordination number=4 + 4 + 4 p34Metallic crystal Structures (金屬的晶體結構) Atomic packing factor (APF) (原子堆積系數(shù)) For FCC structure, APF=0.74Solution:p34Metallic crystal Structures (金屬的晶體結構) Body-centered cubic (BCC) crystal structure (體心立方結構) BCC c

40、rystal structure has a unit cell of cubic geometry, with atoms located at eight corners and a single atom at cube center.除8個頂點外，體心上還有一個陣點.a=b=c, =90oCr, a-Fe,W,p34Metallic crystal Structures (金屬的晶體結構)BCC crystal structure (體心立方結構) Unit cell length a and atomic radius R are related as: .Each BCC unit

41、 has 2 atoms: single center atom + one atom from the eight corner.Corner and center atom positions are equivalent.The coordination number is 8.Atomic packing factor is 0.68.p34Metallic crystal Structures (金屬的晶體結構) Hexagonal close-packed (HCP) crystal structure (六方密堆結構) HCP: The top and bottom faces

42、of the unit cell consist of six atoms that form regular hexagons and surround a single atom in the center. Another plane provides three additional atoms to the unit cell.a=bc,a=g=90o, b=120oCo Cd Mg Zn Tip34Metallic crystal Structures (金屬的晶體結構)HCP crystal structure (六方密堆結構) Unit cell length a and at

43、omic radius R are related as:Each HCP unit has 6 atoms: (1/6) 12+(1/2) 2+3Atomic edge length c=1.633a (ideal value). The coordination number is 12.Atomic packing factor is 0.74.結 構 特 征結 構 類 型 體 心 立 方 （bcc） 面 心 立 方 （fcc） 密 排 六 方 （hcp）點 陣 類 型體心立方面心立方簡單六方點 陣 常 數(shù)aaa，c，c/a =1633最近的原子間距（原子直徑）晶胞中原子數(shù)6配 位 數(shù)8

44、1212致 密 度0.74 典型金屬結構晶體學特點 Metallic crystal Structures (金屬的晶體結構)2.5 Density Computations- Metals (金屬的密度計算):Theoretical density of a metallic solid. n: number of atoms associated with each unit cell.A: Atomic weight.VC: Volume of the unit cell.VA: Avogadros number (6.02x1023 atoms/mol)p37Metallic crys

45、tal Structures (金屬的晶體結構)Example: To calculate the theoretical density of Cu. Known parameters:Atomic radius: 0.128nm, FCC crystal structure, Atomic weight A=63.5g/mol.R= 0.128nmn=4Metallic crystal Structures (金屬的晶體結構)Measured density: 8.94g/cm3.Solution：組成和結合鍵1. 組成 廣義：除有機物和金屬以外。 常見的陶瓷、玻璃、水泥、耐火材料 組分c

46、omponents：硅酸鹽類 氧化物類，氮、碳（不含H）。2. 結合鍵 bonding type 離子鍵 正負離子、鍵強度高、緊密堆積、無 方向性， 金屬氧化物，氧化鎂、氧化鋁 共價鍵 共用電子對、有方向性 如金鋼石、 混合鍵（離子、共價），大多數(shù)。 混合鍵離子鍵和共價鍵之間的過渡。 元素電負性的大小，。 2.6 Ceramic Crystal StructuresIt can be described by associating each lattice point with a group of atoms. 晶體結構空間點陣結構基元Crystal Structures2.6 Ceram

47、ic Crystal StructuresCation（陽離子）and Anion（陰離子） Ceramic Crystal StructuresCarbonSilicon and oxygen結構基元(原子)p31 離子鍵，無方向性。正離子周圍配位多個負離子， 離子的堆積受鄰近質點異號電荷及化學量比限制 堆積形式決定于正負離子的電荷數(shù)和相對大小離子晶體( Ionic Crystal )2.6 Ceramic Crystal Structures Cation（陽離子）and Anion（陰離子） Cations (metallic ions): are positively charged，

48、because they have given up their valence electrons Anions( nonmetallic ions): are negatively charged, because they have accept valence electrons from cations.Examples:Cations: Na (sodium), Ca(calcium) and so onAnions: Cl (chlorine) , F (fluorine) and so on.p38(2) The relative sizes of the cations an

49、d anions. Factors:(1)The magnitude of the electrical charge on each of the component ions. (Electrically neutral)p38CaF2 (calcium fluoride): Ca2+:two positive charges F-: a single negative chargeThe size or ionic radii of the cations and anions (rC and rA) .The coordination numbers and geometriesp40

50、 配位數(shù) CN 正負離子半徑比 R/R 負離子配位多面體2 00.155 線 性 配 位30.1550.225 等 邊 三 角 形40.2250.414 正 四 面 體60.4140.732 正 八 面 體80.7321.000 立 方 體EXAMPLE PROBLEM 3.4Show that the minimum cation-to-anion radius ratio for the coordination number 3 is 0.155SOLUTIONFor this coordination, the small cation is surrounded by three a

51、nions to form an equilateral triangle as shown belowtriangle ABC; the centers of all four ions are coplanar.This boils down to a relatively simple plane trigonometry problem. Consideration of the right triangle APO makes it clear that the side lengths are related to the anion and cation radii rA and

52、 rC as and Furthermore, the side length ratio AP/AO is a function of the angle as The magnitude of is 30, since line AO bisects the 60 angle BAC. Thus, Or, solving for the cationanion radius ratio,Typical Ceramic Crystal StructureAB type crystal structuresAmBp type crystal structuresAmBnOp type crys

53、tal structuresp41AB type crystal structures (1) Sodium Chloride structure (Rock salt structure)(食鹽結構，氯化鈉結構）p41Coordination numbercoordination number = 6(for both cations and anions)StructureFCC, Cl- ions at FCC positions; Na+ at the four octahedral sites.The center of the 12 cube edges Other compoun

54、dsMagnesium oxide (MgO) Calcium oxide (CaO),Iron oxide (FeO)Cl- Na+p41（2）Cesium Chloride Structure （氯化銫結構）Coordination numberStructure Simple cubic, Cs+ fill cubic interstitial sites by the Cl- , but not BCCOther compoundsCesium Bromide (CsBr), Cesium Iodide (CsI), Titanium Chloride( TiCl), Ammonium

55、 Chloride(NH4Cl) Coordination number = 8 (for both ion types)Cl- Cs+p41（3） Zinc Blende Structure (ZnS)（硫化鋅結構）S(001)p42Coordination number coordination number = 4Structure All corner and face positions are occupied by S anions, Zn fill interior tetrahedral positions. Other compounds Gallium Arsenide

56、(GaAs), - semiconductorsFluorite Structure(CaF2)(氟化鈣結構)AB2 type crystal structuresCoordination number coordination number = 8Structure Similar to CsCl, half the center cube positions are occupied by Ca 2+ , F anions locate at the corners.Other compoundsCubic Zirconia (ZrO2), Thorium Oxide (ThO2) Ura

57、nium Oxide (UO2), Cerium Oxide (CeO2)p42Perovskite Structure (CaTiO3)(鈣鈦礦晶體結構)(a) unit cell structure (b) Ca cation coordination number 12AmBnOp type crystal structuresp43Perovskite Structure (CaTiO3)Structure Ca 2+ cations occupy the cube corner; Ti 4+ cations occupy cube center, O 2- anions occupy

58、 the six face centers of the perovskite unit cell.Other compounds Barium Titanate(BaTiO3) (capacitors for electronic applications )p43 立方晶系 Ca2+ 立方體頂角 配位數(shù)12 O2- 面心 配位數(shù)6， Ti4+ 體心 配位數(shù)6 位于八面體間隙 TiO68-八面體 Ti4+八面體中心 Corundum Structure (-Al2O3 alpha alumina)-Al2O3 structure(a) crystal structure (b) close-

59、packed modelCorundum Structure (-Al2O3 alpha alumina)(剛玉)Structure Oxygen anions pack in a hexagonal arrangement; aluminum cations occupy some of the available positions. Application Most widely ceramic material : spark plugs, refractories, electronic packaging substrates and abrasives.Covalent Stru

60、cturesDiamond Cubic Structure （金剛石結構）p48 共價晶體(Covalent Crystal)： 共價鍵；有方向性、飽和性， 配位數(shù)和方向受限制（配位須成鍵） 多由非金屬元素組成(A族) N族元素共價晶體的配位數(shù)為（8N）。 ZnS DiamondStructure Diamond Cubic Structure is a variant of the zinc blende. Carbons occupy both Zn and S positions. Carbon (in its diamond form) are bonded by four coval