激光摆动焊接7075铝合金接头的成形、组织和力学性能  

Forming,Microstructure and Mechanical Properties of 7075 Al Joint Prepared Via Laser Beam Oscillating Welding

作　　者：米高阳 蒋熠鸣 王春明[1] 张铭洋 胡溢洋 肖永康 翟春成 欧阳求保[3] MI Gaoyang;JIANG Yiming;WANG Chunming;ZHANG Mingyang;HU Yiyang;XIAO Yongkang;ZHAI Chuncheng;OUYANG Qiubao(School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074;Guangdong Intelligent Robotics Institute,Dongguan 523830;State Key Laboratory of Metal Matrix Composites,Shanghai Jiao Tong University,Shanghai 200240)

机构地区：[1]华中科技大学材料科学与工程学院,武汉430074 [2]广东省智能机器人研究院,东莞523830 [3]上海交通大学金属基复合材料国家重点实验室,上海200240

出　　处：《机械工程学报》2025年第4期86-95,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金(52075199);广东省基础与应用基础研究基金(2021B1515120060);广东省制造设备数字化重点实验室(2020B11212060014)资助项目。

摘　　要：7系铝合金由于其优异的比强度而成为铝合金中的一个重要分支。与其他系列铝合金相比,7系铝合金由于其焊接性较差限制了在其复杂结构件的大规模应用。因此,实现7系列铝合金有效连接对促进其在大型复杂结构件中的应用具有重要意义。采用高激光功率、高焊接速率的光束摆动焊接技术对7075铝合金的成形、显微组织和力学性能进行系统研究。通过正交试验进行工艺参数优化,结果表明激光功率为4500 W、线能量为80 J/mm、摆动幅度为1 mm、摆动频率为200 Hz时接头力学性能最优,得到了平均抗拉强度为352 MPa的接头,并基于两个描述激光摆动焊接过程实际能量分布的特征参数,建立了工艺参数-焊缝形态-接头强度之间的定量关系。结果表明,焊缝区域由粗等轴晶区、柱状晶区和细等轴晶区组成。拉伸断口EBSD图像表明,7075焊接头在拉伸过程中断裂在焊缝中部的等轴晶区。7 Series aluminum alloy is known as an important branch of the aluminum alloys due to its excellent specific strength.Compared with other series of aluminum alloys,7 series aluminum alloy are limited to the large-scale application of complex structural parts due to the poor welding characteristics.Therefore,the realization of 7 series aluminum alloy fusion welding connection is of great significance to promote its application in large complex structural parts.the formation,microstructure and mechanical properties of 7075 aluminum alloy are systematically studied by high power,high velocity and beam oscillation laser welding technology.The process parameters are optimized through orthogonal experiments,and the results show that the mechanical properties of the joint are optimal when the laser power is 4500 W,the line energy is 80 J/mm,the swing amplitude is 1 mm,and the swing frequency is 200 Hz.A joint with an average tensile strength of 352 MPa is obtained.Based on two characteristic parameters describing the actual energy distribution during laser swing welding,a quantitative relationship between process parameters,weld morphology,and joint strength is established.The results indicated that the weld is composed of equiaxed crystal region,columnar crystal region and fine equiaxed crystal region.The EBSD image of tensile fracture shows that 7075 welding joint breaks in the equiaxed crystal region in the middle of weld during the tensile process.

关 键 词：激光摆动焊接 7075铝合金 显微组织 力学性能 

分 类 号：TG456[金属学及工艺—焊接]