脉冲熔化极气体保护焊熔池振荡行为检测及特征分析  

Detection and Characteristic Analysis of Weld Pool Oscillation Behavior in Pulsed Gas Metal Arc Welding

作　　者：李春凯[1,2,3] 代悦 王嘉昕 顾玉芬 石玗[1] LI Chunkai;DAI Yue;WANG Jiaxin;GU Yufen;SHI Yu(State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050;Wenzhou Engineering Institute of Pump&Valve,Lanzhou University of Technology,Wenzhou 325100;College of Mechanical Engineering,Beijing Institute of Petrochemical Technology,Beijing 102617)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]兰州理工大学温州泵阀工程研究院,温州325100 [3]北京石油化工学院机械工程学院,北京102617

出　　处：《机械工程学报》2024年第16期141-150,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金(52365048);浙江省自然科学基金(LQ21E050023);甘肃省科技重大专项(22ZD6GA008);省部共建有色金属先进加工与再利用国家重点实验室开放课题(SKLAB02019009);光机电装备技术北京市重点实验室开放基金(KF2019-01)资助项目。

摘　　要：熔池表面振荡行为与熔透之间存在明确的物理对应关系,然而在熔化极气体保护焊焊接过程中受熔滴传质过程的影响,想要从熔池表面的多维振荡行为中传感并明析反映熔透状态的振荡特征信息较为困难。基于此,提出采用激光视觉测量脉冲熔化极气体保护焊熔池振荡行为的方法,对未熔透、临界熔透和全熔透状态下的五/单线激光条纹进行采集,采用图像处理算法获取不同熔透状态下熔池的振荡频率、振荡幅度、曲率以及宽度振荡特征信息,并对上述振荡特征与熔池自由表面波动行为以及背面熔透状态之间的相关性进行分析。结果表明:三种熔透(未熔透、临界熔透、全熔透)状态下的熔池表面振荡模式均为行波模式;熔池振荡频率与振荡模式直接相关,不同熔透状态的振荡模式并未发生改变使频率特征也未出现突变;曲率、宽度与熔池上表面体积之间存在相关性,从未熔透到全熔透熔池上表面体积变化较小使曲率、宽度特征也未发生突变;而振荡幅度主要取决于熔池底部约束条件的变化,在全熔透状态下由于熔池底部第二自由表面的出现导致熔池整体振荡的自由度增加,使其出现特征突变。特征突变即该振荡特征在不同熔透状态下具有显著变化。There is a clear physical correspondence between the oscillatory behavior of weld pool surface and penetration.However,it is difficult to sense and resolve the oscillation characteristics of weld penetration from the multidimensional oscillation behavior of weld pool surface,which is influenced by the droplet transfer process during pulsed gas metal arc welding.Based on this,a method for measuring the oscillation behavior of the weld pool of pulsed gas metal arc welding using laser vision is proposed.Five/single line laser stripes in partial,critical and full penetration states were acquired,and image processing algorithms were used to obtain information on the oscillation frequency,oscillation amplitude,curvature and width oscillation characteristics of weld pools in different penetration states.The above oscillation characteristics are also analyzed in correlation with the free surface fluctuation behavior of weld pool and the backside penetration state.The results show that the oscillation mode on the surface of weld pool in the three melt-through states(partial,critical and full penetration)are all traveling wave modes,and the oscillation frequency of weld pool is directly related to the oscillation mode.The oscillation mode did not change for different penetration states,so that the frequency characteristics did not change abruptly either.There is a correlation between curvature,width and volume of the upper surface of the melt pool,and the volume of the upper surface of the weld pool changes less from partial to full penetration,so that the curvature,width characteristics also do not change abruptly.The amplitude of the oscillation depends mainly on the variation of the bottom constraint of the weld pool,which is characterized by a sudden change in the overall oscillation degree of freedom due to the appearance of the second free surface at the bottom in the full penetration state.The characteristic mutation means that this oscillation characteristic has significant changes in different penetration states.

关 键 词：熔池振荡 激光视觉 熔透状态 特征分析 

分 类 号：TG409[金属学及工艺—焊接]