摘要
利用Gleeble-3500热模拟试验机对新型奥氏体不锈钢CHDG-A进行单道次压缩试验,研究了该合金在950-1100℃和0.01-1 s^(-1)条件下的流变应力变化规律及变形组织演变规律。建立了新型奥氏体不锈钢CHDG-A的传统Arrhenius本构模型,耦合应变量后建立改进型本构模型,并引进相关系数R、平均相对误差δ评估改进型本构模型的预测精度。结果表明:在高温热变形过程中,新型奥氏体不锈钢CHDG-A的流变应力值受应变速率以及变形温度的影响显著,且动态再结晶更易在较低应变速率、较高变形温度条件下发生;应用改进型本构模型得到的流变应力预测值与试验值间的相关系数R为0.9944,而平均相对误差值δ仅为1.9952%,说明该本构模型能较好的预测新型奥氏体不锈钢CHDG-A的流变应力。
The change law of flow stress and evolution law of deformed microstructure at 950^(-1)100 ℃ and 0. 01-1 s^(-1) of new austenitic stainless steel CHDG-A were studied by Gleeble-3500 thermol-simulation machine. Traditional Arrhenius constitutive model of new austenitic stainless steel CHDG-A was established. And the modified constitutive model was built coupling with strain. The correlation coefficient R and average relative error δ were introdued to evaluate the accuracy of the modified constitutive model. Results show that the stress of new austenitic stainless steel CHDG-A is influenced by strain rate and deformation temperature significantly,and the dynamic recrystallization is more likely to occur at lower strain rate and higher temperature. The correlation coefficient R and average relative error δ between the predicted value of flow stress and the test value obtained by applying the modified constitutive model are 0. 9944 and 1. 9952%,respectively,which indicates that the constitutive model can accurately predict the flow stress of new austenitic stainless steel CHDG-A.
作者
程晓农
王皎
罗锐
朱晶晶
杨雨童
郑琦
CHENG Xiao-nong;WANG Jiao;LUO Rui;ZHU Jing-jing;YANG Yu-tong;ZHENG Qi(School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2018年第4期122-128,共7页
Journal of Plasticity Engineering
基金
国家高技术研究发展计划(863计划)(2012AA03A501)
江苏省重点实验室开放课题(hsm1304)
关键词
奥氏体不锈钢
高温塑性变形行为
流变应力
本构模型
应变量耦合
austenitic stainless steel
plastic deformation behavior at high temperature
flow stress
constitutive model
coupling withstrain