基于RIK硬化模型的柔性辊弯成形仿真研究

Research on simulation of flexible roll-forming based on RIK hardening model

针对柔性辊弯成形过程中板材反复加载、卸载的复杂成形工艺特点,采用Fortran语言对ABAQUS用户子程序VUMAT进行二次开发,对考虑交叉硬化效应和包辛格效应的材料非线性旋转运动(Non-linear Rotationaland Kinematic,RIK)硬化模型进行有限元程序实现,并利用动力显示ABAQUS/Explicit对柔性辊弯成形过程进行数值模拟。分析了材料RIK硬化模型对该成形过程应力应变的影响规律,并建立柔性辊弯成形起皱临界应力解析模型,探讨了板材的材料参数以及成形工艺参数对失稳起皱的影响。结果表明,非线性旋转运动硬化模型能够很好地体现柔性辊弯成形过程的工艺特点以及皱曲现象。

According to the technology characteristics of repeated loading-unloading during flexible roll-forming,based on the development technique of VUMAT,Fortran language was employed to develop a module for the non-linear rotational and kinematic（RIK） hardening to consider the Crossing and Bauschinger effects,and flexible roll forming process was simulated on ABAQUS/Explicit software platform.The effect of hardening model on flexible roll forming was studied,and a critical wrinkling stress analysis model of sheet in flexible roll forming was established to investigate the influence of the material parameters and forming process parameters on wrinkling.The results show that non-linear rotational and kinematic hardening model can well illustrate the characteristics of flexible roll forming process and wrinkling phenomenon.