特厚板厚度方向形变传递规律的仿真分析

 基于Gleeble热压缩试验、有限元方法对一种HSLA钢特厚板轧制过程中厚度方向变形向心部传递的规律进行了仿真研究。首次从有限元角度定量揭示出特厚板生产中高温、低速、大压下量的轧制规范机理。仿真所用材料本构模型由Gleeble试验数据结合Arrhenius方程所构建，研究了轧制速度、压下量、轧制温度以及板坯厚度对特厚板厚度方向应变分布的影响规律。结果表明，轧制速度小于1 m/s时（平均应变速率小于 0.33 s－1），有利于变形向钢板心部传递，削弱截面效应；压下量越大，钢板等效应变越大，且厚度方向最大等效应变出现的位置向心部偏移；轧制温度对等效应变的分布影响不显著，但是高温轧制有利于减小轧机负荷；板坯越厚，变形分布不均匀性越显著。当板坯厚度为500 mm时，截面的最大、最小等效应变差达到0.2。生产中，在设备允许的情况下，建议特厚板的轧制采用高温、低速、大压下量规范。

Simulation analysis on transfer law of deformation in thickness direction of ultra-heavy plate

Based on Gleeble hot compression test and finite element method，the law of the deformation transferring to the center in the thickness direction of a HSLA ultra-heavy plate was simulated. For the first time，the rolling specification mechanism of the high temperature，low speed and large reduction in the production of the heavy plate rolling was revealed quantitatively from the view of the finite element method. The material constitutive model used in the rolling process simulation is established by the Gleeble thermal compression test results combined with the Arrhenius equation. The effect of the process parameters，rolling speed，reduction，temperature and thickness of the slab on the strain distribution in the thickness direction was studied. The results show that when the rolling speed is less than 1 m/s（average strain rate less than 0.33 s－1），it is beneficial to transfer the deformation to the core of the plate and weaken the section effect. The larger the reduction，the greater the equivalent strain，and the location of the maximum equivalent strain in the direction of thickness is offset to the center. The effect of the rolling temperature on the distribution of the equivalent strain is not significant，but the high temperature rolling can reduce the load of the rolling mill. The thicker the slab is，the more significant the inhomogeneity of the deformation distribution is. When the slab thickness is 500 mm，the difference between maximum and minimum equivalent strain of the section reaches 0.2. In the production，it is recommended that the ultra-heavy plate should be rolled at a high temperature and a low speed and a large reduction under the equipment allows.