激光光斑尺寸对激光焊接熔池、匙孔行为的影响  

Effect of laser spot size on the behavior of molten pool and keyhole in laser welding

作　　者：彭进 许红巧 王永彪 王星星 张永振[2] 龙伟民 张定宇 Peng Jin;Xu Hongqiao;Wang Yongbiao;Wang Xingxing;Zhang Yongzhen;Long Weimin;Zhang Dingyu(Henan International Joint Laboratory of High-efficiency Special Green Welding,Material College,North China University of Water Resources and Electric Power,Zhengzhou 450045,China;National United Engineering Laboratory for Advanced Bearing Tribology,Henan University of Science and Technology,Luoyang 471023,China;China Academy of Machinery Ningbo Academy of Intelligent Machine Tool Co.,Ltd.,Ningbo 315700,China;Henan Key Laboratory of Mechanical Equipment Intelligent Manufacturing,Zhengzhou Light Industry University,Zhengzhou 450002,China)

机构地区：[1]华北水利水电大学材料学院河南省高效特种绿色焊接国际联合实验室,河南郑州450045 [2]河南科技大学高端轴承摩擦学技术与应用国家地方联合工程实验室,河南洛阳471023 [3]中国机械总院集团宁波智能机床研究院有限公司,浙江宁波315700 [4]郑州轻工业大学河南省机械装备智能制造重点实验室,河南郑州450002

出　　处：《红外与激光工程》2023年第7期191-201,共11页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(51705151);河南省博士后科研项目(202003076);河南省重点研发与推广专项(科技攻关)项目(222102220082);河南省本科高校省级大学生创新创业训练计划项目(S202110078023);华北水利水电大学高层次人才科研启动基金项目(201705006);2021年华北水利水电大学教改项目-青年项目;2022年度河南省重点研发与推广专项(科技攻关)项目(232102220052);华北水利水电大学创新创业训练项目(2022XA001)。

摘　　要：在激光焊接中,激光光斑半径的大小直接影响激光功率密度,不同的激光功率密度对熔池流场和小孔的三维形状有影响。然而,关于激光光斑尺寸对激光熔池和小孔行为的影响的研究很少。基于Fluent软件建立了激光焊接热-流耦合模型,研究了激光光斑尺寸下激光焊接过程的匙孔三维瞬态行为及熔池流场。研究结果表明,随着光斑半径的增大,匙孔的深度明显变小。光斑半径分别为0.1 mm和0.15 mm时,焊接过程中均会出现匙孔底部闭合的情况,当光斑半径为0.2 mm时,匙孔未出现闭合的情况,匙孔的稳定性有所提高。随着光斑半径的增大,熔池最大流动速度波动相对较小,熔池尺寸逐渐增大。Objective Laser beam has many advantages,such as good monochromaticity,high brightness,good directivity,etc.Laser technology in laser deep penetration welding process includes a series of complex physical processes,such as the absorption of laser energy by the base metal,the transmission of laser energy through the plasma in the keyhole wall,the change of thermophysical parameters of the base material,the flow behavior of liquid metal in the molten pool,the dynamic fluctuation of keyhole,and phase transformation(melting,solidification of molten pool).In the process of laser welding,when the temperature of the base material in the laser heat source area reaches the critical point of melting and vaporization,the vaporization of the metal produces very high steam pressure,which blows the liquid metal around,thus forming the keyhole.Under the action of recoil pressure,surface tension and other forces,the formed keyhole is always in the process of dynamic fluctuation,that is,the transient change of keyhole.During laser welding,keyhole fluctuates in real time.When the keyhole is closed,welding bubbles will be generated,and welding spatter will be generated on the surface of the molten pool during welding,which will have a great impact on the welding quality.In laser welding,the size of laser spot radius has a direct impact on laser power density,and different laser power density has an impact on the molten pool flowfield and the three-dimensional shape of keyhole.However,there are few studies on the influence of laser spotsize on the behavior of laser welding pool and keyhole.Methods Based on the above analysis,the heat flow coupling model of laser welding was established based onFluent software,the effects of laser spot size on the three-dimensional transient behavior of keyhole and the flowfield of molten pool during laser welding were studied.The control equation adopted continuity control equation,momentum conservation equation and energy conservation equation.The source term was introduced into themomentum conserv

关 键 词：激光焊接 光斑尺寸 匙孔 熔池 

分 类 号：TG456.7[金属学及工艺—焊接]