Abstract：The influences of cooling rate in a wide range of 2～6000℃/min on phase transformation process and microscopic structure of T91 ferritic heat-resistant steels were studied by DIL805A/D high-resolution differential dilatometer. The rule of phase transformation of T91 steel during continuous cooling is clarified . The results show that the martensite critical cooling speed（10℃/min） is determined, and the continuous cooling transformation (CCT) curve is obtained. The quenching rate has a significant effect on the onset temperature of Martensite transformation Ms. This observation is different from the classical theory that claimed the transformation point falls when cooling rate reduces. The quenching rate determines the transform point by affecting the carbon atomic group and internal stress. With the quenching rate increasing, the structure has a tendency of fining, whereas the cooling rate beyond 1000℃/min, it has nothing on the morphology of the structure.
宁保群 严泽生 付继成 别利剑 刘永长. 冷却速率对T91钢相变过程的影响[J]. 钢铁, 2009, 1(7): 71-0.
Ning Bao-Qun 宁保群 . Effect of cooling rate on phase transformation process and microscopic structure of T91 ferritic heat resistant steel. Iron and Steel, 2009, 1(7): 71-0.
2009, Vol. 1 
