Product Code: ICA12_1304

A Comparative Study of Laser, CMT, Laser-Pulse MIG Hybrid and Laser-CMT Hybrid Welded Aluminium Alloy
Authors:
Chen Zhang, Wuhan National Laboratory for Optoelectronics, Huazhong Univ. of Science and Technology; Wuhan, Hubei Peoples Republic of China
Ming Gao, Wuhan National Laboratory for Optoelectronics, Huazhong Univ. of Science and Technology; Wuhan, Hubei Peoples Republic of China
Geng Li, Wuhan National Laboratory for Optoelectronics, Huazhong Univ. of Science and Technology; Wuhan, Hubei Peoples Republic of China
Xiaoyan Zeng, Wuhan National Laboratory for Optoelectronics, Huazhong Univ. of Science and Technology; Wuhan, Hubei Peoples Republic of China
Presented at ICALEO 2012

A so-called cold metal transfer (CMT) welder was introduced into fiber laser-arc hybrid welding in this research. The CMT welding had characteristics of lower heat input and higher productivity compared to other metal inert gas (MIG) technique. The microstructures and mechanical properties of laser welding (LW), CMT welding (CW), laser-CMT (LC) hybrid welding and laser-pulse MIG (LM) hybrid welded AA6061 aluminium alloy sheets were studied. Because of lower heat input, the LW and LC joints had smaller grain size and narrower width of welds than the CW and LM joints. The different microstructures leaded to different mechanical properties. The hardness average values of LW, CW, LC and LM joints were HV67, HV50, HV 65 and HV 57 respectively. The ultimate tensile strength of LW, CW, LC and LM joints reached up to 220MPa, 200MPa, 219MPa, and 198MPa, respectively. At the same time, the LW and LC joints enjoyed less deformation, but the LC welding with filler wire could compensate evaporative base material. These results showed LC welding was a suitable technique for aluminium alloy welding.