摘要
以支承辊常用材料铸态Cr5钢为研究对象,在单道次热压缩试验的基础上,对其在不同试验参数下的热变形行为及热加工图进行分析研究。试验中,变形温度为850~1220℃,变形速率为0.01~1 s^(-1),真应变为0.7。利用试验数据绘制了铸态Cr5钢的真应力-真应变曲线,得出影响流变应力的因素。并通过拟合曲线计算了各待定材料系数,给出了铸态Cr5钢的流动应力方程。最后,基于真应力-真应变曲线,绘制了0.1~0.6应变范围内的热加工图。结果表明:提高变形温度以及减小应变速率可以降低Cr5钢的流变应力,有助于动态再结晶的发生;而随着应变的增加,失稳区域与功率耗散因子变大。Cr5钢高温下最适宜的加工参数区间为:变形温度为1000~1200℃,应变速率为0.03~0.37 s^(-1)。
For common material as-cast Cr5 steel for back-up rollers,based on the single-pass thermal compression test,its thermal deformation behavior and thermal processing map under different test parameters were analyzed and studied,and in the test,the deformation temperature was 850-1220℃,the deformation rate was 0.01-1 s^(-1),and the true strain was 0.7.Then,the true stress-true strain curve of as-cast Cr5 steel was drawn by the test data,and the factors affecting the rheological stress were obtained.Furthermore,the undetermined material coefficients were calculated by fitting the curves,and the rheological stress equation of as-cast Cr5 steel was given.Finally,based on the true stress-true strain curve,the thermal processing map in the strain range of 0.1-0.6 was drawn.The results show that increasing the deformation temperature and decreasing the strain rate can reduce the rheological stress of Cr5 steel,which is conductive to the occurrence of dynamic recrystallization.With the increasing of strain,the instability area and power dissipation factor become larger,and the optimum processing parameters range of Cr5 steel at high temperature is the deformation temperature of 1000-1200℃and the strain rate of 0.03-0.37 s^(-1).
作者
于保宁
郭锐涛
徐航涛
庞锦
何文武
Yu Baoning;Guo Ruitao;Xu Hangtao;Pang Jin;He Wenwu(LuoYang CITIC HIC Casting&Forging Co.,Ltd.,Luoyang 471039,China;CITIC Heavy Industries Co.,Ltd.,Luoyang 471039,China;School of Material Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China)
出处
《锻压技术》
CAS
CSCD
北大核心
2023年第4期236-241,共6页
Forging & Stamping Technology
基金
国家重点研发计划资助项目(2020YFB2008400)。
关键词
铸态Cr5钢
流变应力
热变形行为
变形温度
应变速率
热加工图
as-cast Cr5 steel
rheological stress
thermal deformation behavior
deformation temperature
strain rate
thermal processing map
