在Gleeble 1500热模拟机上对23Co13Ni11Cr3Mo超高强钢进行了大变形等温压缩实验,研究了变形温度、应变速率对奥氏体晶粒尺寸的影响。结果表明:奥氏体晶粒尺寸对数与变形温度倒数、应变速率对数和Z参数对数呈线性关系,降低温度、提高应变速率、增大Z参数,有利于细化晶粒,改善晶粒组织均匀性。根据实验结果得出了23Co13Ni11Cr3Mo钢锻造温度和应变速率范围,建立了奥氏体晶粒尺寸模型,模型预测值与实验值吻合较好。 The large deformation isothermal compression experiment of 23Co13Ni11Cr3Mo ultra-high strength steel was carried out on the Gleeble 1500 thermal simulator to study the effect of deformation temperature and strain rate on the austenite grain size. The results show that there is a linear relationship between the logarithm of austenite grain size and the reciprocal of deformation temperature, the logarithm of strain rate and the logarithm of Z parameter. The decrease of temperature, the increase of strain rate and the increase of Z parameter are beneficial to refine the grain and improve the crystal Granular tissue homogeneity. Based on the experimental results, the forging temperature and strain rate range of 23Co13Ni11Cr3Mo steel were obtained, and the grain size model of austenite was established. The predictions of model agree well with the experimental values.