摘要
采用MMS-200热力模拟试验机,在变形温度950~1200℃以及变形速率0.01~10 s^(-1)条件下对0.07C-0.85Mn-0.16S-0.05Bi钢进行一系列热压缩实验。结果表明,实验钢的流变应力曲线呈现明显的动态再结晶特征,并且流变应力随变形温度的提升或者应变速率的下降而降低。根据不同变形条件下的峰值应力,由Arrhenius模型构建了峰值应力下的本构方程,计算实验钢热变形激活能Q并基于动态材料模型绘制真应变为0.1、0.3、0.5、0.7的热加工图。研究分析了实验钢在不同应变下的失稳区域和合理热加工区域,随着应变的增大,失稳区均出现在高速率变形区,且由低温高速率区向高温高速率区转变。最佳热加工参数为变形温度1020~1200℃、变形速率0.01~0.3 s^(-1)。
A series of hot compression tests on 0.07C-0.85Mn-0.16S-0.05Bi steel is carried out by means of MMS-200 thermal simulation testing machine at the deformation temperature from 950℃to 1200℃and the deformation rates from 0.01 s^(-1) to 10 s^(-1).The results show that rheological curves of the experimental steel are of dynamic recrystallization characteristics,and the flow stress decreases with the increase of deformation temperature or the decrease of strain rate.According to a peak stress under different deformation conditions,hot deformation activation energy Q of the experimental steel is calculated by the constitutive equation under the peak stress constructed by the Arrhenius model,and the hot processing map is established on the base of dynamic material model at true strain of 0.1,0.3,0.5,0.7.By studying and analyzing instability regions and rational hot working regions of experimental steel under different strain,with the increase of strain,instability regions appear in the deformation zone of high rate,and transfer from low temperature deformation zone to high temperature deformation zone of high rates.In thermal processing parameters,the optimal deformation temperature ranges from 1020℃to 1200℃and the optimal deformation rate ranges from 0.01 s^(-1) to 0.3 s^(-1).
作者
邵志保
陈帅帅
李彬周
李长生(指导)
Shao Zhibao;Chen Shuaishuai;Li Binzhou;Li Changsheng(State Key Laboratory of Rolling and Automation,Northeastern University;Beijing Future Research Institute of Angang Group)
出处
《宽厚板》
2021年第5期1-6,共6页
Wide and Heavy Plate
关键词
热变形
流变曲线
本构方程
热加工图
Thermal deformation
Rheological curve
Constitutive equation
Hot processing map
