Welding of additive manufacturing AlSi10Mg alloys using a laser metal deposition process with different heat inputs

Welding of AlSi10Mg alloys fabricated by additive manufacturing (AM) has been recently conducted to meet the demands for joining or repairing them. However, high susceptibility to porosity occurring in weld metal (WM) poses a significant challenge for fusion welding of AM AlSi10Mg alloys. The laser metal deposition (LMD) process has emerged as a promising welding solution due to its low dilution rate for reducing the porosity. In this study, LMD welding of AM AlSi10Mg alloys was carried out employing different heat inputs with five and eight tracks. The study systematically assessed the impact of heat input on porosity, microstructure, and mechanical properties of the welded joints. The results show that the decrease of heat input from 180 to 75 J/mm results in a substantial reduction in porosity from 7.0 to 2.1