铁基合金中热驱动和应力驱动的马氏体形核动力学  

THE KINETICS OF MARtENSITIC NUCLEATION BY THERMAL AND STRESS ACTIVATION IN IRON BASED ALLOYS

作　　者：赵新清[1] 

机构地区：[1]北京航空材料研究院,北京100095

出　　处：《金属学报》2001年第11期1153-1158,共6页Acta Metallurgica Sinica

基　　金：国家自然科学基金50071037资助项目

摘　　要：根据马氏体相变的经典形核理论，对铁基合金中马氏体形核激活能进行了重新估算．结果表明：在非低温时形核激活能比热能低一人数量级，从而证实了铁基合金中马氏体相变的热致形核，深入研究了马氏体形核的动力学，确定了马氏体形核激活能－界面能、激活能－相变驱动力以及相变驱动力－激活体积的关系，这些关系丐相关的实验研究结果相一致．在此基础上，探讨了热能和应力在马氏体形核中的驱动作用，提出了马氏体相变的形核机制，高温条件下的形核由热驱动来完成，而在低温时应力驱动起重要作用．The activation energy of martensitic nucleation in iron based alloys was reconsidered on the basis of classical nucleation theory. It is indicated that thermal activated nucleation possesses very small activation energy, being an order of magnitude lower than the thermal energy. An extensive kinetic study was made to determine the relationships between the activation energy and interfacial energy, the activation energy and driving force, as well as the driving force and activation volume. These relationships are in agreement with the results of kinetic experimental investigations. On this context, the roles played by thermal activation and stress activation in martensitic nucleation were discussed, and a mechanism was developed to explain the origin of martensitic nucleation in iron based alloys. According to this mechanism, at elevated temperature, the thermal activation is predominant in nucleation; at low or cryogenic temperature, the stress activation plays an important part in the nucleation.

关 键 词：马氏体相变 形核 动力学 动力学 铁基合金 激活能 热驱动 应力驱动 

分 类 号：TG111.5[金属学及工艺—物理冶金]