无头铆钉成型过程的有限元仿真与试验分析

Finite Element Simulation and Experimental Analysis of Headless Rivet Forming Process

采用ABAQUS建立有限元分析模型,分析了66°锥形铆模压铆无头铆钉的成型过程。对成型后的试片进行了力学及金相分析,并将结果与普通半圆头铆钉进行对比。研究结果表明,无头铆钉的压铆变形过程为钉杆中间最早涨粗,墩头部分成型,随后钉杆部分逐步与孔壁均匀挤压的过程;随着压铆位移的增加,无头铆钉拉脱强度及剪切强度均呈上升趋势;与传统平铆模成型的半圆头铆钉相比,在锥形铆模的作用下,金属材料向钉杆流动更加均匀,墩头两侧的绝热剪切效应明显弱化。

In this paper,the finite element analysis was established by ABAQUS to analyze the forming process of headless rivet pressed by 66°conical riveting die.Mechanical and metallographic analysis of the formed specimen were carried out,and the results were compared with those prepared by ordinary semi-circular head rivets.The results showed that during pressing deformation,the middle of the nail bar is thickened at the earliest forming the pier head,after which the nail bar is squeezed evenly with the hole wall gradually.With the increase of riveting displacement,the pull-out strength and shear strength of headless rivets elevate.Compared with the semi-circular head rivet formed by traditional flat riveting die,the metal material flows more evenly to the nail rod in conical riveting die,and the adiabatic shear effect on both sides of the pier head is significantly weakened.