铝合金T型接头激光+GMAW复合焊残余应力数值分析  

Numerical Analysis of Residual Stress in Laser+GMAW Hybrid Welding of Aluminum Alloy for T-joint

作　　者：朱征宇[1] 刘辉[1] 王加友[1] 刘文[1] 胥国祥[1] 钱红伟 ZHU Zhengyu;LIU Hui;WANG Jiayou;LIU Wen;XU Guoxiang;QIAN Hongwei(Jiangsu Provincial Key Laboratory of Advanced Welding Technology,Jiangsu University of Science and Technology,Jiangsu Zhenjiang 212100,China)

机构地区：[1]江苏科技大学江苏省先进焊接技术重点实验室,江苏镇江212100

出　　处：《精密成形工程》2024年第4期101-110,共10页Journal of Netshape Forming Engineering

基　　金：国家自然科学基金(51975263,52375340)。

摘　　要：目的研究激光+GMAW复合焊中不同激光功率参数对铝合金T型接头残余应力的影响,从而提高焊接性能。方法分别考虑了热弹塑性理论、传热学以及T型接头几何特性,建立了铝合金T型接头激光+电弧复合焊残余应力的数值分析模型。采用双椭球体热源模型表征电弧热输入与熔滴晗,采用锥体热源模型对激光深熔焊进行描述。基于所建立的T型接头模型,使用ANSYS有限元软件对12 mm厚铝合金激光+GMAW焊T型接头残余应力进行模拟计算,并研究其分布特征;使用X射线衍射法对T型接头处的残余应力进行测量从而对所建模型的准确性进行验证。同时,对比了不同激光功率下铝合金T型接头对残余应力的影响规律。结果当激光功率分别为2、3、4、5 kW时,铝合金T型接头路径L3上的纵向残余应力最大值分别为270、263、258、251 MPa,米塞斯-等效应力最大值分别为265、261、257、250 MPa。结论后焊的焊缝A对焊缝B有明显的热处理作用,使应力明显降低;在T型接头焊缝及近缝区,横向残余应力和厚度方向残余应力峰值均比纵向残余应力峰值小,且随着激光功率的增大,焊缝及近缝区拉应力峰值不断减小。The work aims to study the effect of different laser power parameters in Laser+GMAW hybrid welding on the residual stress in aluminum alloy T-joint,so as to improve the welding performance.A numerical analysis model for evaluating residual stress in T-joint of aluminum alloy subjected to Laser+GMAW hybrid welding by considering thermal-elastoplastic theory,heat transfer and geometric characteristics of T-joint.The arc heat input and droplet enthalpy were characterized by a double ellipsoid heat source model,and the cone heat source model was used to describe laser deep fusion welding.Based on the T-joint model,the residual stress of 12 mm thick aluminum alloy welded by laser+GMAW was simulated with ANSYS finite element software,and its distribution characteristics were studied.The residual stress in the T-joint was measured with X-ray diffraction techniques to verify the accuracy of the model.At the same time,the effect law of aluminum alloy T-joint on the residual stress under different laser power process parameters was compared.When the laser power was 2,3,4 and 5 kW,the maximum longitudinal residual stress along path L3 of the T-joint of aluminum alloy was 270,263,258 and 251 MPa,respectively,and the maximum value of Von-Mises equivalent stress was 265,261,257 and 250 MPa respectively.The results show that the post-welded weld A has obvious heat treatment effect on the weld,and the stress is obviously reduced.The peak value of transverse residual stress and thickness residual stress is smaller than that of longitudinal residual stress in T-joint weld and near seam area,and the peak tensile stress of weld and near weld area decreases with the increase of laser power.

关 键 词：数值模拟 T型接头 残余应力 铝合金 复合焊 

分 类 号：TG404[金属学及工艺—焊接]