30CrMnSi钢马氏体亚结构对力学性能的影响

Effect of martensitic substructure on mechanical properties of 30CrMnSi steel

通过3种不同的工艺对30CrMnSi钢进行热处理,获得不同尺度的马氏体多层次组织。结果表明:奥氏体晶粒大小依赖于加热温度,温度越高,奥氏体晶粒越粗大,马氏体束和块的尺寸也随着原奥氏体的粗大而变大,并且马氏体束和块尺寸与奥氏体晶粒尺寸呈较好的线性关系,表明马氏体束和块的尺寸受原奥氏体晶粒尺寸的控制。EBSD分析结果表明,原奥氏体晶粒尺寸决定了马氏体束和块的尺寸,原奥氏体晶粒越粗大,马氏体束和块越大,细小的各结构单元强化了材料,提高了材料的塑性。

In order to obtain different dimension multilayer martensite microstructure,30 CrMnSi steel was processed by three different heat treatment processes. The results show that the austenite grain size depends on the heating temperature,the austenite grain size increases with the increase of quenching temperature,the size of martensite packets and blocks also increase with the increase of prior austenite grain size,and a better linear relationship exists between the packet,block and prior austenite,which indicate that the size of martensite packets and blocks are determined by prior austenite grain size. EBSD analysis results show that the original austenite grain size affects the size of martensite packets and blocks,the size of martensite packets and blocks is proportional to that of original austenite grain. The fine microstructure strength the initial material and improve the ductility.