Multipass welding of thick section steels using autogenous CO2 laser welding and CO2 laser-MIG hybrid welding  

作　　者：胡连海 黄坚 李铸国 吴毅雄 

机构地区：[1]Shanghai Key Laboratory of Materials Laser Processing and Modification,Shanghai Jiao Tong University, Shanghai, 200240 [2]Materials Science and Engineering Institute, Shijiazhuang TiedaoUniversity, Shijiazhuang, 050043.

出　　处：《China Welding》2012年第4期49-54,共6页中国焊接（英文版）

摘　　要：Laser multipass welding techniques for thick section steels have been developed using a new type of UV combined narrow groove. The shape and sizes at the bottom of groove are determined by analyzing the plasma behavior using high speed photographic equipment. A stable autogenous CO2 laser welding process and greater penetration are generated at the root pass because of strong reduction of the plasma volume. According to the waveforms of welding current and arc voltage, and the interaction between the arc and the laser induced plasma, a suitable groove angle is obtained. Laser-double MIG hybrid welding process is studied and the optimum distances between the laser and two arcs are determined. By using autogenous CO2 laser welding, CO2 laser-MIG hybrid welding and laser-double MIG hybrid welding, 28 mm thick steel plates are welded with four passes. The welds produced are assessed by X-ray. No crack is found and there is only a small amount of pores. The experimental results show that the multipuss welding procedures proposed can realize the joining of thick section steels with high efficiency and good quality.Laser multipass welding techniques for thick section steels have been developed using a new type of UV combined narrow groove. The shape and sizes at the bottom of groove are determined by analyzing the plasma behavior using high speed photographic equipment. A stable autogenous CO2 laser welding process and greater penetration are generated at the root pass because of strong reduction of the plasma volume. According to the waveforms of welding current and arc voltage, and the interaction between the arc and the laser induced plasma, a suitable groove angle is obtained. Laser-double MIG hybrid welding process is studied and the optimum distances between the laser and two arcs are determined. By using autogenous CO2 laser welding, CO2 laser-MIG hybrid welding and laser-double MIG hybrid welding, 28 mm thick steel plates are welded with four passes. The welds produced are assessed by X-ray. No crack is found and there is only a small amount of pores. The experimental results show that the multipuss welding procedures proposed can realize the joining of thick section steels with high efficiency and good quality.

关 键 词：CO2 laser welding thick section steels narrow groove PLASMA metal transfer 

分 类 号：TG456.7[金属学及工艺—焊接] TG260.6