Weld Defects in Laser-Welded 7A52 High-Strength Aluminum Alloy Plates with Varying Thicknesses

This study aims to explore a method suitable for welding 7A52 high-strength aluminum alloy plates with continuously varying thicknesses and the causes of microscopic defects in welds in order to improve welding quality. Comparative tests were conducted to analyze weld defects and deformation when welding the aluminum alloy plates with varying thicknesses at constant laser power. The laser power required for melting welds at varying-thickness positions was estimated. Weld defects and deformation when welding aluminum alloy plates with varying thicknesses at continuous variable laser power were detected. The causes of microscopic weld defects during constant-power welding were analyzed. The welding defects and deformation and the welding quality were improved by welding aluminum alloy plates at continuous variable power.