摘要
基于相变动力学和热力学原理 ,讨论了椭球形铁素体晶核在奥氏体晶界形核及长大的动力学 ,根据形变促进相变的理论 ,变形引起位错密度增加而提高了奥氏体内的存储能 ,考虑了变形存储能增加对形核的促进作用 ,提出了预测控轧控冷过程的α晶粒尺寸的方法·用该方法模拟计算应变量、轧制温度、冷却速率及化学成分等因素对α晶粒尺寸的影响 ,与已有的实验结果吻合良好 ,表明这种理论处理方法可用来模拟这种相变过程·
On the basis of transformation kinetics and thermodynamics, the nucleation and growth of elliptical ferrite grain on austenite grain boundary were investigated. To study the effect of work hardening austenite on the nucleation and growth rates of ferrite phase, the free energy of work hardened austenite was calculated by adding the strain energy of dislocation to that of non deformed austenite. In view of enhancement of deformation on transformation, the strain energy associated with dislocation was considered as one part of driving force for nucleation, which was introduced into the calculation of nucleation rate. A mathematical model of α grain size after transformation under controlled rolling and controlled cooling was presented, and the effect of strain, rolling temperature, cooling rate and chemical composition on α grain size was modeled by this model. The simulated results are in agreement with experiment results. This model can be used to model this kind of transformation.
出处
《东北大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2002年第2期144-147,共4页
Journal of Northeastern University(Natural Science)
基金
国家重点基础研究发展规划项目 (G19980 615 0 9)
