T7钢在奥珠转变中富碳的分布研究

Study of Higher Carbon Distribution during the Transformation of T7 Steel from Austenite to Pearlite

综合运用全自动相变仪、扫描电镜及电子探针技术研究了成分已均匀化的 T7钢在珠光体转变温度范围等温所形成的先共析铁素体周围奥氏体中的碳分布。发现先共析铁素体周围存在有富碳奥氏体薄层 ,且此富碳奥氏体薄层中的碳分布并非都是连续的 ;此一富碳奥氏体薄层的特征与随后转变所形成的珠光体及马氏体形态相关。

The carbon distribution in austenite around the proeutectoid ferrite of a piece of T7 steel,which it has been homogenized at high temperature and cooled rapidly to pearlitic transformation temperature,held for a short time and then quenched ,was investigated with optical,electron scanning microscope and electron probe.It was discovered that there is a austenitic layer with higher carbon around proeutectoid ferrite and that the distribution of carbon in the austenitic layer is not all continuous and homogeneous,and that the characteristic of austenitic layer with higher carbon around proeutectoid ferrite is closely related to the lamellar aggregation of carbon and also to the morphology of pearlite or martensite around the proeutectoid ferrite.