【摘要】 建立连续冷却过程多相转变模型,并实现了对冷却过程中各相转变量的数值预测。用传统叠加模型和Cahn微分模型分别对40Cr钢连续冷却过程中组织分布进行了模拟计算,结果表明,考虑动力学参数n随温度变化的相变动力学微分方程计算结果与实际结果更为接近。为分析晶粒尺寸对相变过程的影响,结合不同奥氏体化温度下的等温膨胀实验,讨论了考虑晶粒尺寸时的相变动力学模型的应用范围,不同晶粒度下的相变参数n相同时,模型才能准确反应实际相变过程。更多还原

【Abstract】 Transformation kinetics model of austenite decomposition during continuous cooling process was established.Volume fraction of phases in 40Cr steel was predicted using the traditional additivity rule and Cahn theory.The calculated results based on Cahn’s theory with the parameter n as a function of temperature agree well with experimental results.To study the influence of grain size on the transformation,dilatometric analysis of the steel with different austenitizing temperature was investigated.Based upon the model and experimental results,the transformation kinetic model considering grain size can be applied to simulate the transformation process with n as a constant.更多还原