铝合金旋转激光焊接小孔与熔池耦合动态行为数值分析  

Numerical Analysis on Dynamic Behaviour of Keyhole and Molten Pool during Rotating Laser Welding of Aluminum Alloy

作　　者：王学礼 张坦 胥国祥[1] 龚祺龙 WANG Xueli;ZHANG Tan;XU Guoxiang;GONG Qilong(School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)

机构地区：[1]江苏科技大学材料科学与工程学院,江苏镇江212003

出　　处：《热加工工艺》2024年第7期23-27,共5页Hot Working Technology

基　　金：国家自然科学基金资助项目(51975263)。

摘　　要：旋转激光对熔池的搅拌作用可以有效增加激光热源的作用范围,抑制激光焊接过程中的气孔等常见缺陷,提高焊接接头质量。由于旋转激光热源的物理特性,小孔和熔池的动态行为比传统的激光焊接更复杂。采用数值模拟的方法,在同时考虑小孔、反冲压力和熔池的耦合条件下,建立适用于激光焊的三维数学模型。该模型可以描述旋转激光焊接过程中小孔的动态行为特征、流体流动以及气泡在熔池中的形成过程和机理。结果表明,在常规激光焊接中,小孔呈现深而窄且处于不稳定的动态平衡过程,通常会形成气泡。如果气体未能及时溢出熔池,会形成气孔。随着激光旋转频率的增加,小孔变浅变宽,动态行为趋于稳定,可有效抑制气孔的形成。The inhibit defects such as pores,and improve the quality of joint.Due to physical characteristics of the rotating laser heat source,the dynamic behavior of keyhole and molten pool is more complicated than that of the conventional laser welding.The method of numerical simulation was adopted,and the three-dimensional model of the laser welding was developed,which takes the coupling of keyhole,recoil pressure and molten pool into account.The model can describe the dynamic behavior characteristics of keyholes,fluid flow,and the formation process and mechanism of pores in weld during rotating laser welding.It can be concluded that in conventional laser welding,the keyhole is deep,narrow and in unstable dynamic process,which usually produces bubbles.If the air fails to overflow the molten pool in time,the pores are formed.With the increase of laser rotation frequency,the keyhole becomes shallow and wide,and the dynamic behavior tends to be stable,which can effectively inhibit the formation of pores.

关 键 词：旋转激光 小孔 熔池流动 数值模拟 

分 类 号：TG402[金属学及工艺—焊接]