双相钢中残留奥氏体的分布及演变规律  

Distribution and Evolution of Retained Austenite in Dual-Phase Steel

作　　者：李辉[1] 段路昭[1] 米振莉[1] 赵征志[1] 唐荻[1] 

机构地区：[1]北京科技大学冶金工程研究院,北京100083

出　　处：《华南理工大学学报（自然科学版）》2013年第10期92-96,共5页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(50904006);北京科技大学中央高校基本科研业务费专项资金资助项目(2302011FRFTP11005B)

摘　　要：在双相钢(铁素体+马氏体,DP)的基础上通过合理的热处理工艺得到一定量的残留奥氏体,达到强度和塑性的良好结合.通过光学显微镜分析、X射线衍射分析和背散射电子衍射分析等方法研究了该DP钢的微观组织,并进一步分析了残留奥氏体随形变量的演变规律.结果表明:残留奥氏体晶粒细小,主要呈粒状,均匀地分布在铁素体或马氏体的晶界位置,也有少量分布在铁素体内部;残留奥氏体的转变主要集中在形变量小于10%之前,之后的转变与应变成线性关系,拉伸断裂后未发现残留奥氏体.A certain amount of retained austenite in the dual phase steel was obtained through a rational heat treatment process,and the steel thus achieved a good combination of strength and plasticity.Then,the microstructure of the DP steel was investigated by means of the optical metallography,XRD and the electron back-scatter diffraction （EBSD）,and the evolution rules of the retained austenite during the deformation were discussed.The results show that （1） the retained austenite is fine and mainly granular,and most of it distributes uniformly at the boundaries of ferrites and/or martensites with few in the ferrites; （2） the transformation of retained austenite mainly occurs at the deformation extent of less than10％,and it is linearly related to strain at the deformation extent of more than 10％ ;and （3） in the EBSD observation,the retained austenite is not found in the fractured sample after tensile fracture.

关 键 词：双相钢 热处理 残留奥氏体 形变量 演变规律 

分 类 号：TG156.31[金属学及工艺—热处理]