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1、Ceramic Materials Structures and Properties,Ceramic Materials 陶瓷材料,Inorganic materials 無機材料Nonmetallic materials 非金屬材料Most ceramics are compounds between metallic and nonmetallic elementsComposed of at least two elements,and often moreAtomic bonding in ceramics ranges from purely ionic to totally co
2、valent,Electronegativity 電負度、陰電性,Stable and unstable cation-anion coordination configuration,Cations are ordinarily smaller than anionscation 陽離子anion 陰離子,Coordination Number 配位數,2,3,4,6,8,Coordination Number 配位數,Cation-Anion Radius Ration rC/rA,0.155,0.155-0.225,0.225-0.414,0.414-0.732,0.732-1,rC/r
3、A 1 配位數12,Crystal Structures,AX TypeRock Salt Structure 岩鹽結構Cesium Chloride Structure 氯化銫結構Zinc Blende(Sphalerite)Structure 閃鋅礦結構AX2 TypeFluorite Structure 螢石結構、氟石結構ABX3 TypePerovskite Structure 鈣鈦礦結構AB2X4 TypeSpinel Structure 尖晶石結構,Rock Salt Structure 岩鹽結構,NaCl,MgO,MnS,LiF,FeO,rNa+=0.102 nmrCl=0.18
4、1 nmrNa+/rCl=0.564,Cesium Chloride Structure 氯化銫結構,CsCl,rCs+=0.170 nmrCl=0.181 nmrCs+/rCl=0.939,Zinc Blende Structure 閃鋅礦結構,ZnS,ZnTe,SiC,ZnO,rZn2+=0.074 nmrO2=0.140 nmrZn+2/rO2=0.529,Fluorite Structure 螢石結構,CaF2,ZrO2,UO2,PuO2,ThO2,rCa2+=0.100 nmrF=0.133 nmrCa+2/rF=0.8,Perovskite Structure 鈣鈦礦結構,BaTi
5、O3,SrZrO3,SrSnO3,Interstitial position填隙位置、間隙位置,Tetrahedral position 四面體位置Octahedral position 八面體位置,close-packed structure 最密堆積結構、緊密堆積結構,Crystal structure,Hexagonal Close-Packed(HCP)六方最密堆積ABAB.Stacking SequenceFace-Centered Cubic(FCC)面心立方ABCABC.Stacking Sequence,Determine Crystal Structures,Stoichio
6、metry 化學計量Charge NeutralityCation-anion radii ratios(coordination number)Covalent character,Ceramic Density Computation,Number of formula units/unit cell,AC:atomic weight of cation AA:atomic weight of anion VC:Volume of unit cellNA:Avogadros number,Silicate Ceramics 矽酸鹽陶瓷,Silica 矽石、二氧化矽,Crystalline
7、structure of SilicaQuartz 石英Cristobalite(Crystobalite)白矽石、方矽石Tridymite 鱗石英、鱗矽石The strong Si-O bond leads to a strong,high melting temperature(1710C),Cristobalite(Crystobalite)白矽石、方矽石,Silica Glass 矽石玻璃,fused silica or vitreous silica 熔凝矽石或玻化矽石B2O3 and GeO2Network formerCaO and Na2ONetwork modifierTiO
8、2 and Al2O3IntermediateModifiers and Intermediates lowers the melting point and viscosity of a glass,Crystalline silicon dioxide,Noncrystalline silicon dioxide,Silicate 矽酸鹽,Two-dimensional silicate sheet structure(Si2O5)2,Layered Silicates,Can change the counterions(相對離子)this changes layer spacingth
9、e layers also allow absorption of water Mica 雲母 KAl3Si3O10(OH)2Bentonite 膨土、火山黏土used to seal wellspackaged dryswells 2-3 fold in H2Opump in to seal up well so no polluted ground water seeps in to contaminate the water supply,Structure of kaolinite clay高嶺黏土,Carbon 碳,Diamond 鑽石metastable state 介穩態、準穩態
10、Graphite 石墨Fullerene 芙、芙樂、富勒、芙樂烯、富勒烯C60Buckminsterfullerenes 巴克明斯特芙樂烯 Buckyball 巴克球,Diamond cubic crystal structure,Structure of Graphite,Structure of a C60 Molecule,Structure of a Carbon Nanotube,Imperfections in Ceramic,Imperfection 缺陷Electroneutrality 電中性Atomic Point DefectVacancy 空位Interstitial
11、填隙、間隙Defect StructureFrenkel defect 夫倫克耳缺陷Schottky defect 肖特基缺陷Stoichiometry or Nonstoichiometry,Defect Structure,Frenkel defect,Schottky defect,Impurities in Ceramics,Electroneutrality 電中性Solid solution 固溶體substitutional typeinterstitial type,Diffusion in Ionic Materials,Diffusion in ionic material
12、s usually occurs by a vacancy mechanismElectroneutrality 電中性,Ceramic Phase Diagrams,MgO-Al2O3,Brittle Fracture of Ceramics,brittle fracture 脆性斷裂plastic deformation 塑性形變fractography 斷口形像學crack 裂痕、裂紋、裂縫branch or bifurcate 分叉,Stress-Strain Behavior,Stress 應力Strain 應變flexural strength 抗彎強度、抗撓強度、撓曲強度modulus of rupture 破壞模數 fracture strength 破裂強度 bend strength 彎曲強度,Plastic Deformation,Crystalline ceramicsNoncrystalline ceramicsViscosity 黏度、黏性,
