A comparative study on the microstructure and properties of copper joint between MIG welding and laser-MIG hybrid welding

作者：Zhang, Lin-Jie; Bai, Qing-Lin^*; Ning, Jie; Wang, An; Yang, Jian-Nan; Yin, Xian-Qing; Zhang, Jian-Xun

来源：Materials and Design, 2016, 110: 35-50.

DOI：10.1016/j.matdes.2016.07.117

• Copper
• Arc welding
• Laser-arc hybrid welding
• Microstructure
• Properties

Aiming to support the spread and application of laser-MIG hybrid (HYBRID) welding technology of pure copper in industry field, this work compared the microstructure, mechanical properties, thermal properties, and electric properties of 4 mm thick T2 copper joints between double-sided MIG (DMIG) welding and single-pass laser-MIG hybrid (HYBRID) welding. Compared with the DMIG welded joint, the HYBRID welded joint exhibited narrower heat-affected zone (HAZ), finer grains in fusion zone (FZ) and HAZ, and lower degree of softening. The tensile strengths of the HYBRID welded joint and the DMIG welded joint were 74% and 69% that of the base metal (BM). The tensile fracture of the HYBRID welded joint primarily consisted of dimples, while that of the DMIG welded joint consisted of both dimples and layered crack morphology. The HYBRID welded joint exhibited better electrical and thermal conductivities than the DMIG welded joint. The electrical conductivities of copper joints before and after annealing changed little, meanwhile impurity elements and micro-voids were found in the FZ of the welded joints. These results illustrated that impurity elements and micro-voids in the FZ should be primarily responsible for the decline of electrical conductivity.

• 出版日期2016-11-15
• 单位西安交通大学