Effect of grain size on the intrinsic mechanical stability of austenite in transformation-induced plasticity steels:The competition between martensite transformation and dislocation slip  

作　　者：D.P.Yang T.Wang Z.T.Miao P.J.Du G.D.Wang H.L.Yi 

机构地区：[1]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China

出　　处：《Journal of Materials Science & Technology》2023年第31期38-43,共6页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation(No.52101128);the National Key R&D Program(No.2018YFE0306102);the Postdoctoral Science Foundation(No.2022M710021);the Northeastern University Postdoctoral Research Fund of China(No.20220202).

摘　　要：The deformation accompanied by austenite to martensite trans-formation was first studied in Fe-Ni alloys,high-Mn steels,and austenitic stainless steels with a full austenite microstructure.The plasticity of these steels can be improved by the trans-formation during deformation and hence they were named as transformation-induced plasticity(TRIP)steels[1].Over the past few decades,a series of TRIP steels with multiphase microstructure for automotive applications were developed.These steels contain-ing a certain amount of austenite were called TRIP-assisted steels,such as low-alloy TRIP steels[2],carbide-free bainitic steels[3],δ-TRIP steels[4],quenching and partitioning steels[5],and medium-Mn steels[6].The mechanical property of TRIP steels is largely determined by the mechanical stability of austenite[7]which de-pends on the chemical composition[8],grain size[9],orientation[10],and morphology[11]of austenite grains,as well as the nature of neighboring phases[12].In most cases of TRIP-assisted steels,larger austenite grains transform to martensite earlier or faster than smaller austenite grains with the increase of macrostrain[13-18],indicating lower mechanical stability.However,larger austen-ite grains usually contain less C and Mn[13,17-19]and suffer more strain than smaller grains during deformation[20],it doesn’t mean that grain refinement increases the mechanical stability of austen-ite.

关 键 词：AUSTENITE MARTENSITE TRANSFORMATION 

分 类 号：TG161[金属学及工艺—热处理]