热轧带钢层流冷却过程中温度与相变耦合预测模型

Temperature and phase transformation coupling prediction model of hot rolled strip cooled on the run-out table

建立了温度与相变耦合有限元模型,对带钢轧后冷却过程中带钢厚度和宽度方向的温度场进行了模拟计算.建模过程中,考虑带钢的各金相组织的密度、导热系数、比热容等物性参数为温度的函数,取各相的线性平均值用于计算.根据连续等温转变实验曲线,采用Avrami方程和Scheil可加性法则计算带钢相变潜热,实现温度和相变耦合求解.计算结果表明,带钢经过层流冷却后,沿厚度方向存在着一定的温差,带钢温度沿宽度方向分布不均匀,和现场实测结果吻合.

A temperature and phase transformation coupling finite element model was established to calculate the temperature field of hot rolled strip cooled on the run-out table along thickness and width direction. In this model, each metal phase＇s physical parameters such as density, heat conduct coefficient, specific heat etc were considered to be functions of temperature and the linear mean value of all phases was used during calculation. Based on TTT curves of the material studied, Avrami function and Scheil additivity rule were used to calculate the latent heat of phase transformation, and the coupling solving of temperature and phase transformation was carried out. The results of simulation indicate that temperature difference exists along the thickness direction of strip and non-uniform temperature distribution along the width direction of strip, which match well with actual measurement on spot.