Life cycle analysis for laser welding of alloys

•Lump parameter analysis provides accurate energy consumption and weld width size.•Weld width extends uniformly on the surface free from the large size asperities.•Life cycle assessment demonstrates importance of waste material in laser welding process.•Laser welding of Inconel 625 is the most contributing to environmental damage. Laser welding of AISI 304, Ti6Al4V, and Inconel 625 alloy was realized. The topological and metallurgical variations in the welded region are presented briefly and life cycle analysis for the welding process due to each alloy is introduced. The analytical tools including optical and scanning electron microscopes are used to characterize the weld sections. The energy consumption during welding and the size of the welded sections are formulated using the lump parameter analysis. The energy consumption during welding and the geometric features of the weld sites is measured. The findings are compared with those obtained from the lump parameter analysis. It is found that the energy consumption predicted and obtained from the measurements are in good agreement for the welding of each material. The prediction of the weld width from the lump parameter analysis differs from that of the measurements; however, the differences are within the acceptable limits. Because of the high pressure assisting gas effect and the local evaporation from the weld surface, some material is ablated from the top surface of the weld site. The gravitational and the surface tension forces result in the molten material extension from the bottom side of the welded zone. The laser welding of Inconel 625 alloy has the most contribution towards environmental destruction as compared to those of other materials welded. Consequently, the materials selection for the laser welding remains crucial for minimizing the environmental impact.