G50超高强度钢热变形行为及本构关系研究  

Research on hot deformation behavior and constitutive relationship of G50 ultra-high-strength steel

作　　者：郝爱国[1] 吉卫[1] 郝花蕾 HAO Aiguo;JI Wei;HAO Hualei(Institute of Mechanical Manufacturing Technology,China Academy of Engineering Physics,Mianyang 621900,Sichuan China)

机构地区：[1]中国工程物理研究院机械制造工艺研究所,四川绵阳621900

出　　处：《锻压装备与制造技术》2020年第5期124-128,共5页China Metalforming Equipment & Manufacturing Technology

摘　　要：使用Gleeble-1500型热模拟机对G50超高强度钢在应变速率为0.001~10s^-1、变形温度为800~1200℃条件下的流变应力行为进行了压缩试验研究。结果表明:G50钢热压缩变形中的动态回复与动态再结晶不明显,流变应力随应变速率的增加而增加,随温度的增加而降低;G50钢的高温流变行为可用Zener-Hollomon参数描述,从流变应力、应变速率和变形温度的相关性,得出了G50钢高温变形的材料常数和本构方程。计算出G50钢的变形激活能为Q=416985.9522J·mol^-1,材料常数为A=1.3475×1016s^-1,n=6.2391,α为0.0081;计算得到了G50超高强度钢Arrhenius方程;利用双曲正弦模型,得到高温拉伸峰值应力和Z参数的解析式。The Gleeble-1500 thermal simulator has been used to study the flow stress behavior of G50 ultra-high-strength steel under the conditions of strain rate of 0.001-10 s^-1 and deformation temperature of 800-1200℃.The results show that the dynamic recovery and dynamic recrystallization of G50 steel during hot compression deformation are not obvious,the flow stress increases with the increase of strain rate,and decreases with the increase of temperature;the high temperature rheological behavior of G50 steel can be described by Zener-Hollomon parameters From the correlation between flow stress,strain rate and deformation temperature,the material constants and constitutive equations of high temperature deformation of G50 steel have been obtained.The activation energy for deformation of G50 steel has been calculated as Q=416985.9522 J·mol^-1,the material constant is A=1.3475×1016 s^-1 s^-1,n=6.2391,and α is 0.0081;the Arrhenius equation of G50 ultra-high-strength steel has been calculated;the analytical formulas of the high temperature tensile peak stress and the Z parameter have been obtained through the hyperbolic sine model.

关 键 词：超高强度钢 热压缩变形 流变应力 变形激活能 

分 类 号：TG111[金属学及工艺—物理冶金]