摘要
热环轧是目前M50钢制轴承套圈的主流制造工艺,其工艺流程较长,长时间的保温导致晶粒粗大且耗时耗能。将电脉冲工艺与热环轧工艺相结合,提出电脉冲辅助轴承套圈热环轧冷却(EP-HRR)的新方法,研究了不同峰值电流辅助下热环轧试样的组织与力学性能演变。结果表明:脉冲电流可降低M50钢相变发生的活化能,促进奥氏体再结晶,有助于缓解轧制过程中的局部应力集中;随着峰值电流增大,变形晶粒向回复晶粒转变,进而向再结晶晶粒转变,这归因于脉冲电流非热效应下再结晶所需自由能的降低以及再结晶形核速率的提升;高峰值电流辅助M50钢制轴承套圈热环轧冷却有助于降低试样的各向异性及截面硬度,电脉冲辅助冷却一定程度上可起到回火功效。
Hot ring rolling is currently the mainstream manufacturing process for M50 bearing rings.Its process flow is relatively long,and long holding time results in coarse grains,time consumption and energy consumption.A new method for hot ring rolling with electric pulse assisted cooling(EP-HRR)of the rings is proposed by combining electric pulse process with hot ring rolling process.The evolution of microstructure and mechanical properties of hot ring rolling samples are studied under different peak current assistance.The results show that the pulse current can reduce activation energy of phase transformation in M50 steel,promote austenite recrystallization,and help alleviate local stress concentration during rolling process;as the peak current increases,the deformed grains transform into recovered grains,and then transform into recrystallized grains,which can be attributed to decrease in free energy required for recrystallization and increase in recrystallization nucleation rate under non thermal effect of pulse current;the hot ring rolling with high peak current assisted cooling of the rings can help reduce anisotropy and section hardness of the samples,and the electric pulse assisted cooling has a tempering effect to some extent.
作者
尹飞
陈裕
华林
邓加东
王丰
YIN Fei;CHEN Yu;HUA Lin;DENG Jiadong;WANG Feng(School of Automotive Engineering,Wuhan University of Technology,Wuhan 430070,China;Hubei Key Laboratory of Advanced Technology for Automotive Components,Wuhan University of Technology,Wuhan 430070,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;Hubei Longzhong Laboratory,Xiangyang 441000,China)
出处
《轴承》
北大核心
2024年第11期77-85,共9页
Bearing
基金
国家重点研发计划资助项目(2020YFA0714900)。
关键词
滚动轴承
高温轴承钢
环轧
再结晶
显微组织
力学性能
rolling bearing
high temperature bearing steel
ring rolling
recrystallization
microstructure
mechanical property
