贝氏体相变的动力学特征(一)  

Dynamics Characteristics of Bainite Phase Transformation(1)

作　　者：刘宗昌[1] 计云萍[2] 任慧平[2] 

机构地区：[1]内蒙古科技大学分析测试中心,内蒙古包头014010 [2]内蒙古科技大学材料与冶金学院,内蒙古包头014010

出　　处：《热处理技术与装备》2016年第6期1-5,共5页Heat Treatment Technology and Equipment

基　　金：国家自然科学基金(51261018)

摘　　要：研究贝氏体相变动力学具有重要意义。贝氏体相变动力学特征表明贝氏体铁素体的形成不是扩散过程,也不是切变机制。从共析分解到贝氏体相变是一个逐渐演化的过程,海湾区可以将贝氏体相变与共析分解完全分离,贝氏体铁素体形成的孕育期极短,转变速度比共析分解快得多。采用贝氏体钢进行了激光共聚焦显微图像的动态直接观察,观察到贝氏体在奥氏体晶界形核,向晶内长大,测得620℃的长大速度为275μm/s,温度降低时,长大速度减慢。It is of great significance to study the dynamics of bainite phase transformation. The dynamics characteristics of bainite transformation show that the formation of bainite ferrite is neither diffusion nor shear process. It is a gradually evolved process from eutectoid decomposition to bainite transformation. The bay area can separate bainite transformation from eutectoid decomposition completely. The incubation period of the bainite ferrite formation is extremely short,so the transition velocity of bainite transformation more quickly than that of the eutectoid decomposition. The in situ observation of nucleation and growth of bainite was carried out using laser scanning confocal microscopy. The results show that bainite nucleates in the austenite grain boundary and grows towards the grain interior. The measured growth rate of bainite is275μm/s,and with the decrease of the temperature,the rate slows down.

关 键 词：贝氏体相变 TTT图 扩散 切变 热激活跃迁 

分 类 号：TG142.1[一般工业技术—材料科学与工程]