微合金中碳钢的热压缩变形流变行为研究

为了对冷镦钢的生产过程进行数值模拟分析,优化其生产工艺,在MMT-200热模拟机上进行热压缩变形实验,研究了微合金中碳钢热变形流变应力行为,试验温度为800～950℃,应变速率为0.01～20 s-1.结果表明:真应力随变形温度的升高而减小,随应变速率的增大而增大,表现出正的应变速率敏感性;材料热变形过程中伴随着铁素体...

Flow stress behavior of microalloying medium carbon steel under hot compression deformation

To simulate the production process of cold heading steel,and optimize their production process,the flow stress behavior of microalloying medium carbon steel was studied by hot compression deformation experiments carried on a MMT-200 thermal simulation machine at temperature of 760~880 ℃ and strain rates of 0.01~20 s-1.The results show that the flow stress decreases as temperature increases and strain rate decreases,which indicates that the microalloying medium carbon steel is a positive strain rate sensitive material.The dynamic recrystallization and excessively precipitation of ferrite occurs during hot compression deformation.The flow stress behavior can be represented by a Zener-Hollomon parameter in the hyperbolic sine equation,its hot deformation activation energy is 306.79 kJ/mol.