摘要
利用GAMBIT软件建立了光纤连续激光和内径为2 mm空心Tungsten Inert Gas(TIG)电弧在稳态条件下的激光同轴复合电弧数学模型,对其进行分区域网格划分,最小网格长度为0.1 mm;用FLUENT软件中的用户自定义函数(UDF)功能添加了激光热源、动量方程源项、能量方程源项和材料物理性能设置,计算得到了150 W功率激光和118 A电流下同轴复合电弧的温度场、速度场及电弧空间压力、电场和磁场分布,并与相同条件下的空心单TIG电弧作了对比。结果表明:激光同轴复合电弧温度场变化明显,最高温度和高温区面积显著增加,电弧能量密度显著提高,熔透能力大大增强;由于激光同轴复合电弧温度升高和钨极腔内压力增大,电弧中上部等离子体流动速度明显加快;激光同轴复合电弧的电弧压力降低,电磁场强度减小,电弧静压力减小。最后用实验验证了模拟结果的可靠性。
Objective Laser-arc hybrid welding technology has advantages of high welding efficiency and good joint quality.However,it is currently based on the paraxial composite,which has high requirements for welding direction,and the keyhole instability causes welding defects and other problems.Laser-arc coaxial composite welding has advantages of good heat source symmetry,stable welding process,high joint quality,and good reachability of the welding torch joint.However,research on laser-arc coaxial composite welding is limited because of the difficulty of welding torch head processing.There are two kinds of coaxial recombination,and the structure of passing a laser through a hollow tungsten electrode is relatively simple and easier to achieve than splitting the laser into two beams and then converging them at the focus.However,research on the composite arc characteristics of lasers and hollow tungsten inert gas(TIG)arc has not been reported.Therefore,the study on the characteristics of laser coaxial composite arc in this paper can provide theoretical support for technology development.Methods The mathematical model of laser coaxial composite arc of a fiber continuous laser and 2mm hollow TIG welding arc under steady-state conditions was established using GAMBIT software.The regional mesh was divided and the minimum mesh was 0.1mm.The laser heat source,momentum source term,and energy source term were added,and reasonable material physical property parameters were set using user-defined functions(UDF)FLUENT software.The temperature field,velocity field,spatial pressure,electric field,and magnetic field distribution of the coaxial composite arc under 118-A current and 150-W laser power were calculated and compared with those of the hollow single TIG arc under the same conditions.Finally,experiments verify the penetration ability of laser coaxial composite arc.Results and Discussions The calculation results show that compared with the hollow TIG arc,the maximum temperature and high-temperature area of the laser coaxial compo
作者
雷正
朱宗涛
李远星
刘艳
陈辉
Lei Zheng;Zhu Zongtao;Li Yuanxing;Liu Yan;Chen Hui(Hui Key Laboratory of Advanced Technologies of Materials,Ministry of Education,School of Materials Science and Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610031,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2021年第18期94-103,共10页
Chinese Journal of Lasers
