Hybrid laser/MIG welding was carried out for API X80 pipeline steel using different welding parameters. Influence of welding current on weld appearance, microstructure variation and hardness across the weld cross-section was investigated. Increasing welding current is benificial for larger weld penetration and high welding efficiency. However, increase of welding current can result in coarser microsturctures in CGHAZ near ArcZ. Maximum hardness value occurs in the vicinity of fusion zone of LaserZ, and a slight reduction is observed with larger welding current.
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