The metadynamic recrystallization (MDRX) model is established, and the coefficients determined by multiple linear regression analysis are used to describe the microstructure evolution of SA508Gr.4N steel. The effects of compression temperature of 950–1150 °C, strain rate of 0.001–0.1 s⁻¹, pre-strain of 0.3–0.6, initial austenite grain size (IAGS) of 136–552 μm, and interval time of 1–300 s on the MDRX kinetics and microstructure evolution were analyzed, using two-pass compression test method on Gleeble thermo-mechanical simulator. The results show that MDRX kinetics and austenite grain size are strongly dependent on compression temperature and strain rate, MDRX volume fraction increases with increasing compression temperature and strain rate, and the grain size decreases with increasing strain rate and decreasing compression temperature, while less affected by the pre-strain and IAGS. Meanwhile, the values predicted using MDRX model and the ones calculated from experiment are compared, and the results show that the proposed model can give a reasonable estimate of MDRX behavior for SA508Gr.4N steel.

建立了亚动力学重结晶模型，通过多元线性回归分析确定了SA508Gr.4N钢的组织演变。压缩温度950–1150°C，应变速率0.001–0.1 s ^-1的影响，在格力宝（Gleeble）热压机上采用两遍压缩测试方法，分析了MDRX动力学和微观结构演变的0.3-0.6预应变，初始奥氏体晶粒尺寸（IAGS）136-552μm和间隔时间1-300 s。机械模拟器。结果表明，MDRX动力学和奥氏体晶粒尺寸强烈依赖于压缩温度和应变速率，MDRX体积分数随压缩温度和应变速率的增加而增加，而晶粒尺寸随应变速率和压缩温度的降低而减小，而受应变的影响较小预应变和IAGS。同时，比较了用MDRX模型预测的值和实验计算的值，结果表明所提出的模型可以合理估计SA508Gr.4N钢的MDRX性能。