马氏体相变的形核问题  

NUCLEATION OF MARTENSITIC TRANSFORMATION

作　　者：孟庆平[1] 戎咏华[1] 徐祖耀[1] 

机构地区：[1]上海交通大学材料科学与工程学院,上海200030

出　　处：《金属学报》2004年第4期337-341,共5页Acta Metallurgica Sinica

摘　　要：在对马氏体相变经典形核理论阐述的基础上,仔细考察了Fisher等以统计物理对形核几率的原始推导,指出一些学者近年来否定Cohen和Kaufman马氏体相变形核几率计算的错误,确定形核几率计算中的形核能垒△G*应为临界核胚中所有原子的总自由能变化,而不应为核胚中单个原子的自由能.对他们佐证均匀形核观点所引用的实验给予了重新解释,对他们提出的形核模型进行了评论.最后简要提出研究马氏体相变形核问题的几个可能方向.On the basis of describing the classical nucleation theory of martensitic transformation and considering in detail the original derivation of nucleation probability through statistical physics by Fisher et al, the present work points out the mistakes appearing in the recent works of some authors who negated the calculation of the nucleation probability of martensitic transformation with Cohen and Kaufman. The nucleation barrier DeltaG* in calculating the nucleation probability should be the free energy change of total atoms in an embryo, rather than that of an atom. The experiments cited by these scholars, supporting their viewpoint of homogeneous nucleation of martensitic transformation, are re-explained and the nucleation model suggested by them is critically reviewed by us with the basic concept of statistical physics. Finally, several research directions are briefly suggested for study of the nucleation of martensitic transformation.

关 键 词：马氏体相变 形核几率 形核能垒 

分 类 号：TG151[金属学及工艺—热处理]