碳锰含量对低碳(锰)钢过冷奥氏体形变过程转变动力学的影响

提高低碳(锰)钢中碳含量，低碳(锰)钢形变强化相变孕育期明显延长，转变动力学曲线整体向高应变方向移动．提高锰含量，相变孕育期有所延长，转变动力学过程明显变缓．提高碳、锰含量，钢中铁素体形核率增大，晶粒细小，碳的影响程度比锰显著．过冷奥氏体形变过程铁素体转变分三个阶段，第一阶段符合Cahn的“位置饱和”机制，第二、三阶段不符合“位置饱和”机制。

Transformation Kinetics of Undercooled Austenite During Deformation of Low Carbon Mn Steels with Different Carbon and Manganese Contents

The effects of carbon and manganese on the kinetics and the ferrite nucleation of deformation enhanced ferrite transformation (DEFT) in low carbon (Mn) steels were investigated. It was found that the addition of carbon prolongs the transformation incubation period dramatically, which retards the transformation kinetics. However, the transformation incubation period is somewhat prolonged, and the kinetics becomes much more sluggish as the manganese content increased. The more pronounced refinement is achieved as the carbon or manganese content increased because of the higher nucleation rate, especially in the steels with high carbon content. The process of DEFT in the tested steels can be divided into three stages according to the characteristics of the DEFT kinetics, the first stage obeys Cahn site saturation mechanism, but the other two stages not.