电磁铆接过程数值模拟

电磁铆接是一种新型铆接工艺,铆接过程中材料的应变率高,铆钉材料的变形方式不同于普通铆接.通过电磁铆接过程的数值模拟分析影响铆接质量的因素,重点分析铆模几何构形对铆钉镦头成形的影响,为铆模优化设计提供了理论依据.数值模拟发现改变铆模倾角可以改变镦头区的应力分布,从而改变镦头区应变分布;减小铆模倾角可以减小最大剪应力,从而减小剪应变,防止镦头裂纹的产生.镦头金相组织表明数值模拟结果符合实际情况.

Numerical simulation of electromagnetic riveting process

Electromagnetic riveting is a new type of riveting process. In the process, the strain rate of metal material is high and the mode of the deformation of rivet material is different from that of conventional riveting methods. The purpose of the work is to analyze the factors which make an effect to the riveting quality, in particular, to analyze the relation between geometrical form of riveting die and the deformation of rivet tail and provide the theoretical references for optimizing design of riveting die. It is found that the angle of riveting die affects obviously shear stress and shear strain of rivet tail; And decreasing the angle can improve the distribution of the strain and prevent riveting cracks in rivet tail. Experiments indicate that the results of the numerical simulation are proper.