贝氏体相变的过渡性特征

对35CrMo钢等多种材料奥氏体化后进行贝氏体等温淬火,得到少量贝氏体+马氏体+残留奥氏体的整合组织。应用JEM-2100透射电镜和QUANTA-400环扫电镜等设备观察了贝氏体组织的形貌和亚结构。综合分析了贝氏体相变的特征。研究表明,过冷奥氏体随着温度的降低具有转变贯序,贝氏体相变在组织形貌、亚结构方面具有过渡性。贝氏体相变动力学具有交叉性、重叠性、变温性和等温性的过渡性特征。贝氏体相变中铁原子和置换原子以非协同热激活跃迁方式位移,表明贝氏体形核长大具有过渡性。

Transient Characteristics of Bainite Transformation

35 CrMo steel and other materials were austenitized and quenched isothermally in the bainite transformation zone,with the result that a integrated microstructure consisting of a small amount of bainite, martensite and retained austenite was developed.The morphology and substructure of the bainite were observed by JEM-2100 transmission electron microscope and QUANTA-400 environmental scanning electron microscope.The characteristics of bainite transformation were comprehensively analyzed.The results show that with the decrease in the temperature,the supercooled austenite exhibits transformation sequence,and the bainite transformation has transient characteristics in structure morphology and substructure.The bainite transformation dynamics has transient characteristics,such as intersecting,overlapping,variable- temperature and isothermal characteristics.The iron and replacement atoms will shift through the medium of non-synergic thermal activation transition during the bainite transformation,which shows the transient characteristics of the nucleation and growth of the bainite.