缺陷的类型 People are like crystals.It is the defects in them that make them interesting. Sir F.Charles Frank Point defects (vacancies,interstitials) OLine defects (dislocations) OPlane defects (grain boundaries, surfaces)
㔎䱋ⱘ㉏ൟ Point defects (vacancies, interstitials) Line defects (dislocations) Plane defects (grain boundaries, surfaces) People are like crystals. It is the defects in them that make them interesting. Sir F. Charles Frank
Defects in Crystalline Ceramics 。Vacancy(空位) terstitial ·Interstitial(填隙) ·Dislocation(位错) Grain Boundary(晶界) Cation Interstitial Anion Vacancy Cation Vacancy Schotky Defect Electro- Frenkel Defect_ neutrality
Defects in Crystalline Ceramics • Vacancy(ぎԡ) • Interstitial(฿䱭) • Dislocation(ԡ䫭) • Grain Boundary(⬠) Cation Interstitial Anion Vacancy Cation Vacancy Schotky Defect Frenkel Defect Electroneutrality
-、Point Defects 口Vacancy(空位) ▣Interstitial(填隙) ▣Substitutional(替代) ●Larger ●Smaller ▣Frenkel ▣Schottky
ϔ ǃPoint Defects Vacancy (ぎԡ) Interstitial(฿䱭) Substitutional(᳓ҷ) Larger Smaller Frenkel Schottky
1.Vacancies A vacancy is the absence of an atom in the lattice. In ionic crystals (e.g NaCl)vacancies occur in pairs (Na Cl)so that charge balance is maintained. Also called a Schottky Defect Vacancies allow diffusion through the crystal: Vacancy point defect -associated with a point in the crystal
1. Vacancies A vacancy is the absence of an atom in the lattice. In ionic crystals (e.g NaCl) vacancies occur in pairs (Na + Cl) so that charge balance is maintained. Also called a Schottky Defect. Vacancies allow diffusion through the crystal: Vacancy : point defect - associated with a point in the crystal
Vacancies 通常，空位数量随温度增加而增加 表征空位特性的有2个参数：空位形成能E,和空 位迁移能Emv 对包含N个原子的晶体，热平衡时，空位数量随温 度的关系为： n Nexp 对晶体，空位形成能与熔点T近似有： Ev ≈10 kgTm
Vacancies 䗮ᐌ, ぎԡ᭄䞣䱣⏽ᑺࡴ㗠ࡴ. 㸼ᕕぎԡ⡍ᗻⱘ᳝2Ͼখ᭄: ぎԡᔶ៤㛑EVぎ ԡ䖕⿏㛑Emv. ᇍࣙNϾॳᄤⱘԧ, ⛁ᑇ㸵ᯊ, ぎԡ᭄䞣䱣⏽ ᑺⱘ݇㋏Ў: − = k TE n Nexp B V ᇍԧ, ぎԡᔶ៤㛑Ϣ❨⚍Tm䖥Ԑ᳝: ≈10 B m V k T E