摘要
本文对 Cr12MoV 钢经不同热处理工艺所得组织再加热转变时奥氏体形成动力学进行了研究,并观察了淬火+高温回火的组织再加热时奥氏体的形核位置。结果表明,淬火组织和淬火+高温回火组织比球化退火组织再加热时奥氏体形成过程的转变激活能小。原奥氏体晶界是奥氏体形核的优先部位,说明低温循环淬火得到细小的奥氏体晶粒会大大提高再加热时奥氏体的形核率。
In the present study,the kinetics of austenite formation of thedifferent prior structure for Cr12MoV tool steel using dilatometer areinvestigated,and the nucleation sites of austenite are also observed by themetallographie microscope.It is shown that the activation energy of austeniteformation with the quench hardened or the quench hardened and temperedprior structure is smaller than that with the spheroidal anneal prior structure.The original austenitic grain boundary is the preferential nucleation site ofaustenite.
关键词
工具钢
奥氏体
晶粒细化
机理
tool steel
austenitic grain refining
TTA curves of austenitic formation
activation energy
