基于8字形摆动的钢/铝激光焊接头组织和性能  

Microstructure and properties of steel/aluminum laser welded joints based on 8-shaped oscillation

作　　者：李田 严佑锐凌 张明军[3] 张跃敏[1] LI Tian;YAN Youruiling;ZHANG Mingjun;ZHANG Yuemin(School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo,454000,China;State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle,Hunan University,Changsha,410082,China;Hunan Provincial Key Laboratory of Intelligent Manufacturing Technology for High Performance Mechanical Equipment,Changsha University of Science and Technology,Changsha,410114,China)

机构地区：[1]河南理工大学,机械与动力工程学院,焦作454000 [2]湖南大学,整车先进设计制造技术全国重点实验室,长沙410082 [3]长沙理工大学,机械装备高性能智能制造湖南省重点实验室,长沙410114

出　　处：《焊接学报》2025年第2期112-119,135,共9页Transactions of The China Welding Institution

基　　金：河南省自然科学基金资助项目(232300421334);河南省科技攻关计划项目(242102230053)。

摘　　要：采用8字形摆动模式开展钢上铝下激光搭接焊试验,利用金相显微镜、扫描电镜、电子万能试验机分析摆动频率对接头宏观形貌、微观组织、断裂特征及力学性能的影响,结合高速摄像及仿真计算探讨各摆动频率对焊缝成形性、熔池稳定性、熔池形貌特征以及接头力学性能变化的作用机制.结果表明,焊缝表面成形性及熔池流动稳定性随摆动频率的增加显著下降,熔池的形貌特征与能量密度分布有直接的对应关系,低频摆动时界面IMC层厚度小且熔池内均匀分布的Al元素具有固溶强化效果,高频摆动时的强涡流作用使得Al元素在界面聚集,并导致界面IMC层厚度增加,而层状相厚度的增加是导致接头剪切拉伸性能下降的主要原因,与未摆动模式相比,接头的最大剪切拉伸力提高了31.5%,8字形摆动可以通过调控界面IMC层厚度显著提高接头的强度及韧性.The laser lap welding experiment of steel on aluminum alloys was carried out by using the 8-shaped oscillation mode.Metallographic microscope,scanning electron microscope and electronic universal testing machine were used to analyze the influence of oscillation frequency on the macroscopic morphology,microstructure,fracture characteristics and mechanical properties of the joint.The effects of oscillation frequency on weld formability,morphology and stability of molten pool,and mechanical properties of joint were discussed by using high-speed cameras and simulation calculations.The results show that the formability of the weld surface and the stability of the molten pool flow significantly decrease with the increase of oscillation frequency,and there is a direct correspondence between the morphology characteristics and energy density distribution of the molten pool.During low-frequency oscillation,the thickness of the IMC layer at the interface is small and the uniform distribution of the Al element in the molten pool has a solid solution strengthening effect.During high-frequency oscillation,the strong vortex effect causes the Al element to aggregate at the interface,leading to an increase in the IMC layer thickness at the interface,and the increase of the layered phase thickness is the main reason for the decline of the shear tensile performance of the joint.Compared with the non-oscillation mode,the maximum shear tensile force of the joint is increased by 31.5%and the toughness is also significantly improved.The 8-shaped oscillation can significantly improve the strength and toughness of the joint by regulating the thickness of the interface IMC layer.

关 键 词：钢/铝激光搭接焊 8字形摆动 金属间化合物 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]