电磁辅助激光熔化沉积的残余应力

摘要

In view of the problem of large residual stress in laser melting deposition ,this paper summari-zes the mechanism and the effective methods of eliminating the stress .Based on the principle of electro-magnetic field ,the method utilising electromagnetic field to assist laser melting deposition is proposed in order to reduce the residual stress .The process of laser melting deposition assisted by electromagnetic field is simulated using ANSYS parametric programming language APDL ,and the temperature field and the change rule of residual stress are analyzed .The results show that the axial electromagnetic force can effectively reduce the residual stress in the workpiece .Method of X ray diffraction combined with elec-trolytic corrosion is used to measure the residual stress ,and the test results verify the effectiveness of the assisted electromagnetic field .%针对激光熔化沉积内部残余应力较大的问题,对其产生的机理作了分析.基于电磁场的应用原理,提出电磁辅助激光熔化沉积以降低其残余应力的方法.利用ANSYS参数化编程语言APDL模拟了电磁辅助激光熔化沉积的过程,分析了成形件残余应力的变化规律,结果表明同步加载轴向电磁力能较好地消减成形件内部残余应力.采用X射线衍射结合电解腐蚀的方法进行深度方向的残余应力测量试验,试验结果验证了电磁辅助的有效性.