铸态25Mn钢热变形行为及流变应力本构模型研究  

Study on the hot deformation behavior and flow stress constitutive model of as-cast 25Mn steel

作　　者：戚玉超[1,2] 雷步芳[1,2] 李永堂[1,2] 巨丽[1,2] 

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024 [2]太原科技大学金属材料成形理论与技术山西省重点实验室,山西太原030024

出　　处：《锻压装备与制造技术》2015年第5期92-97,共6页China Metalforming Equipment & Manufacturing Technology

基　　金：国家自然科学基金重点项目(51135007);国家自然科学基金项目(51205270);国家自然科学基金项目(51405325);山西省自然科学基金项目(2014011026-2);高等学校博士点基金优先发展计划项目(20111415130001)

摘　　要：为实现铸态25Mn钢热辗扩的数值模拟与制定合理的热成形工艺参数,基于Gleeble-3500热模拟试验机进行了单道次热压缩试验,系统地分析了各变形参数(变形温度、变形速率、初始晶粒尺寸)对铸态25Mn钢热变形及流变应力的影响,通过对实验数据进行线性分析推导出铸态25Mn钢的热压缩本构方程。研究结果表明:当变形温度越高、应变速率越小、初始晶粒越细小时,越容易发生动态再结晶;流变应力的预测值与实验值较吻合,且预测值最大误差仅为5.9%。In order to realize numerical simulation of hot rolling and establish hot forming process parameters for as-cast 25Mn steel, one-pass compression test of as-cast 25Mn steel has been conducted on Gleeble-3500 thermal-simulation testing machine. The influence of each deformation parameter （temperature, strain rate, initial grain size） on hot deformation and flow stress of as-cast 25Mn steel has been analyzed systematically. The flow stress constitutive equation of as-cast 25Mn steel during hot compression has been deduced through linear analysis of experiment data. The study results show that dynamic re-crystallization occurs more easily when the deformation temperature increases but deformation velocity and initial grain size deerease. The predicted flow stress of as-cast 25Mn steel is consistent with experimental results, and the maximum error between the predicted and the experimental results is only 5.9%.

关 键 词：铸态25Mn钢 热压缩变形 流变应力 本构方程 

分 类 号：TG142.41[一般工业技术—材料科学与工程] TG314.4[金属学及工艺—金属材料]