三辊非对称滚弯成形的数值仿真及试验验证

基于有限元法对三辊非对称滚弯成形工艺进行了研究，对比分析了三辊非对称滚弯成形和三辊对称滚弯成形过程中，变形区应力场、板材上表面的塑形应变场及卷制力的变化规律。仿真结果表明：侧辊位移进给量相同的工况下，三辊非对称滚弯成形的卷制力大于三辊对称滚弯成形的卷制力；三辊非对称滚弯变形区的纵向应力和径向应力均大于三辊对称滚弯成形的纵向应力和径向应力；三辊非对称滚弯成形板材压弯段的成形质量高于三辊对称滚弯成形的成形质量。最后，经三辊非对称滚弯试验验证，有限元模型的成形误差为6.8%，有较高的精度。

Numerical Simulation and Experimental Verification of Asymmetrical Three-roll Bending Process

The stress field of deformation zone, the stain field of upper plate surface and the changes of roll bending forces were analyzed during the asymmetrical and symmetrical roll bending process by the finite element(FE) simulation method. The simulation results show that the bending force during the asymmetrical roll bending process is larger than that during symmetrical roll bending under the same feed distance of the side roll. Compared to the asymmetrical roll bending process, the longitudinal and radial stress in deformation zone in the symmetrical roll bending process are smaller. The forming accuracy of the asymmetrical roll bending process of the pre-bending section  is higher than that of symmetrical roll bending process.The experimental verification of a typical plates for the asymmetrical roll bending process was conducted, the result show that the forming error of FEA model is 6.8%.The FEA model has a higher forming accuracy.