论文部分内容阅读
采用Gleeble-3800热模拟试验机,在温度850℃~1200℃、应变速率0.001s~(-1)~10s~(-1)下进行热压缩实验,研究300M高强钢的热变形行为。根据双曲正弦函数,分析全应变条件下流动应力与Z参数间的关系,得到300M高强钢的变形激活能Q及参数A、n、α的值,建立全应变本构方程。基于动态材料模型,建立300M高强钢的热加工图,并讨论了300M钢组织演化规律。结果表明,考虑应变补偿的本构方程,在实验条件内计算的流动应力与实验所测结果吻合度较高;随变形温度的升高及应变速率的减小,300M钢的奥氏体晶粒尺寸增加;变形温度900℃~1 200℃、应变速率0.001s~(-1)~0.1s~(-1)是300M高强钢较佳的热加工工艺范围。
Hot deformation tests were carried out at temperatures of 850 ℃ ~ 1200 ℃ and strain rate of 0.001s ~ (-1) ~ 10s ~ (-1) using Gleeble-3800 thermal simulation machine to study the thermal deformation behavior of 300M high strength steel. Based on the hyperbolic sine function, the relation between flow stress and Z parameter under full strain condition is analyzed to obtain the value of deformation activation energy Q and parameters A, n, α of 300M high strength steel and to establish the all-strain constitutive equation. Based on the dynamic material model, the hot working diagram of 300M high strength steel was established and the microstructure evolution of 300M steel was discussed. The results show that, considering the constitutive equation of strain compensation, the calculated flow stress in the experimental conditions is in good agreement with the experimental results. With the increase of deformation temperature and the decrease of strain rate, the austenite grain size The deformation temperature is 900 ℃ ~ 1 200 ℃, and the strain rate of 0.001s ~ (-1) ~ 0.1s ~ (-1) is the preferred thermal processing technology for 300M high strength steel.