Characteristics of microstructure and fatigue resistance of hybrid fiber laser-MIG welded Al–Mg alloy joints

In this study, the microstructures, mechanical properties and fatigue strengths of the hybrid laser-MIG welded joints were investigated. The detailed microstructures of the hybrid welded joints were carried out using OM and TEM. The causes of the strengths loss of the hybrid welded joints were studied from aspects of solute strengthening, precipitates hardening, and grain boundary strengthening. The fatigue strengths of the hybrid welded joints,...