摘要
测量了50Cr5NiMoV钢的等温膨胀曲线,研究了等温膨胀曲线中孕育期的读取误差对拟合相变动力学参数n的影响,提出了一种获得参数n的方法,建立了50Cr5NiMoV钢的等温奥氏体分解相变动力学模型。应用叠加原理预测连续冷却条件下奥氏体分解相变体积分数,借助连续冷却膨胀曲线对模型参数进行了验证。同时,利用该模型,基于商用ABAQUS软件,对50Cr5NiMoV支承辊热处理过程进行了温度-组织模拟。研究结果表明,该模型能够准确地预测支承辊热处理过程中显微组织演变规律。
The isothermal expansion curve of 50 Cr5 NiMoV steel had been measured. The influence of the reading error of incubation time in isothermal expansion curve on fitting phase transformation kinetic parameter n had been studied, and a method to obtain the parameter n had been put forward. A kinetic model for isothermal austenite decomposition transformation of 50 Cr5 NiMoV steel was established. The volume fraction of austenite decomposition phase transformation under continuous cooling was predicted by superposition principle, and the model parameters were verified by means of continuous cooling expansion curve. At the same time, by using this model and commercial ABAQUS software, the temperature-microstructure simulation of the 50 Cr5 NiMoV back-up roll during heat treatment was carried out. The results show that the model can accurately predict the microstructure evolution of the 50 Cr5 NiMoV back-up roll during heat treatment.
引文
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