不锈钢金属定子衬套液压成形回弹特性

Springback characteristics of stainless steel metal stator screw lining in hydroforming

金属管件塑性成形过程中不可避免地存在回弹问题,导致零件的实际成形尺寸产生偏差,影响零件的制造和装配精度。综合考虑摩擦润滑、管件尺寸、材料力学参数、加载路径和加载压力等参数,建立金属定子衬套液压成形数值模型,分析成形管件回弹对等壁厚金属定子衬套成形质量的影响。结果表明,选用304不锈钢成形金属定子衬套,其回弹量对成形管件壁厚分布和截面位移影响较小,但是卸载后,成形管件等效应力大幅降低,从而降低了成形管件内部的残余应力。因此,采用管件外高压成形方法加工金属定子衬套,可以获得尺寸精度满足要求的等壁厚金属定子衬套。为金属定子衬套实际选材和模具设计提供了理论参考。

The springback problem inevitably exists in metal tube plastic forming,leading to actual size deviation and affecting parts manufacturing and assembling accuracy.Comprehensively considering the effect of friction,tube size,material mechanics parameters,pressure and loading paths,the external pressure numerical model of metal stator screw lining is established,so as to analysis of the effect of springback on metal stator screw lining forming quality.The simulated results show that,the wall thickness distribution and the displacement of cross section is less affected by springback when selecting 304 stainless steel,however the equivalent stress of the metal stator screw lining falls dramatically after uninstalling,and the residual stress of the metal stator screw lining is reduced effectively.Therefore,it is feasible to satisfy the dimensional accuracy requirements of the metal stator screw lining.It provides theoretical reference for the selection of materials and the design of dies in actual manufacture.