新型Nb-Ti微合金钢连续冷却转变规律  

Continuous Cooling Transformation Behaviour of Nb-Ti Micro-Alloyed Steel

作　　者：李鑫[1] 赵捷[1] 包俊成[1] 宁保群[1] 

机构地区：[1]天津理工大学材料科学与工程学院,天津300191

出　　处：《物理测试》2013年第6期8-11,共4页Physics Examination and Testing

基　　金：国家自然科学基金资助项目(51104107);轧制技术及连轧自动化国家重点实验室开放课题基金资助项目(2009011);天津市自然科学基金资助项目(12JCYBJC11800)

摘　　要：通过Nb-Ti复合微合金化钢奥氏体连续冷却过程的热模拟试验,结合显微组织观察和显微硬度测试,结果表明:Nb-Ti复合微合金化钢的临界淬火速率约为23℃/s,并且有很好的淬透性。随着冷却速率的增大,相变开始温度和结束温度均有所下降,室温组织中铁素体的含量逐渐减少,先期容易发生贝氏体转变,使后期形成马氏体板条或马氏体片变得更细,从而有利于强度和韧性的提高。Abstract：Thermal simulation of continuous cooling process, microstructure observation and microhardness test were carried out on the Nb-Ti composite micro-alloyed austenitic steel. The result indicates that the critical quenching speed of Nb-Ti microalloyed steel is about 23 ~C/s with very good hardenability. With the increasing of the cooling rate, the phase transformation starting and ending temperature decrease and the ferrite content was decreased at room temperature. The hainite transformation easily happened at the early stage of phase transformation, making the size of later produced martensite decrease and strength and toughness of tested steel increase.

关 键 词：NB-TI 微合金钢 连续冷却转变 静态CCT曲线 热模拟 

分 类 号：TG142.33[一般工业技术—材料科学与工程]