【摘要】 将不变线理论和O点阵理论应用于fcc／bcc（bct）马氏体相变的可滑移生长界面的设计,建立了马氏体形核与长大的 晶体学模型.通过模型分析表明: fcc／bcc（bct）马氏体形核与长大过程是通过（121）fcc型择优界面推移进行的,界面上的错配 位错可以完成马氏体晶体学唯象理论（PTMC）要求的点阵不变变形（LID）,但LID要稍滞后于界面迁移,即在马氏体形核与长 大过程中推移界面新相一侧存在一未发生LID的新相薄区;当相变温度达到马氏体相变点Ms时,母相奥氏体与这一薄区的晶格 常数比为3/2^1/2,这一几何条件和Olson-Cohen形核模型中要求扩展位错层错区界面能γ≤0是等价的.更多还原

【Abstract】 The crystallography of fcc/bcc（bct） martensite transformation, including nucleation and growth, has been discussed from the viewpoint of invariant-line and O-lattice theory. The formation of martensite is accomplished by the immigration of well-defined glissile interface （121）fcc type and its misfit dislocations can produce the lattice invariant deformation （LID） on the basis of phenomenal theory of martensitic crystallography （PTMC）, however, LID is retarded slightly after the migration of interphase （121）fcc, i.e. a thin plate-like zone exists without LID in martensite near the well-defined interface. When the temperature reduces to the Ms point, the lattice parameter of austenite matrix is 3/2^1/2 times that of the martensite without LID. This critical condition for spontaneous transformation agrees with that the stack fault energy in matrix is less than zero according to Olson and Cohen’s nucleation model.更多还原