Influence of on-line tempering parameters on microstructure of medium-carbon steel

作     者：Hua Zhang Yan-xin Wu Jian-xun Fu Jie Xu Qi-jie Zhai 

作者机构：State Key Laboratory of Advanced Special SteelShanghai UniversityShanghai 200072China 

出 版 物：《Journal of Iron and Steel Research International》 (国际钢铁研究杂志)

年 卷 期：2017年第24卷第1期

页      面：59-66页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：sponsored by Key Projects in the National Science&Technology Pillar Program of China(2013BAE07B00) State Natural Science Fund Projects of China(51474142,51671124) Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(2012) China Postdoctoral Science Foundation(2015M580316) 

主　　题：Medium-carbon steel Ultra-fast cooling On-line tempering Phase transformation kinetics 

摘      要：A new process involving ultra-fast cooling（UFC）and on-line tempering（OLT）was proposed to displace austempering process,which usually implements in a salt/lead bath and brings out serious pollution in the industrial *** optimization of the new process,involving the evolution of the microstructure of medium-carbon steel during various cooling paths,was *** results show that the cooling path affected the final microstructure in terms of the fraction of pearlite,grain size and distribution of cementite in *** the cooling rate or decreasing the OLT temperature contributes to restraining the transformation from austenite to ferrite,and simultaneously retains more austenite for the transformation of *** is also noted that bainite was observed in the microstructure at the cooling rate of 45℃/s and the OLT temperature of 500℃.Through either increasing the cooling rate or decreasing the OLT temperature,the distribution of cementite in pearlite is more dispersed and grain is *** the possibility of industrial applications into account,the optimal process of cooling at 45℃/s followed by OLT at 600℃ after hot rolling was determined,which achieves a microstructure containing nearly full pearlite with an average grain size of approximately 7μm and a homogeneously dispersed distribution of cementite in pearlite.