Stress field and mechanical properties of laser metal deposited aluminum alloys

Through grooves in the 6 mm thickness ZL114A aluminum plate were repaired by the laser metal deposition process, and the filling powder was AlSi10Mg powder. In order to determine the scanning strategy, the residual stress generated with different scanning strategies was calculated by numerical simulation. The process of laser melting deposition was realized by the path scanning method with the smallest residual stress, and the influence of defects and heat input on the mechanical properties of the test workpiece was further studied. The results show that the layer-by-layer scanning strategy generated less the residual stress compared with the parallel scanning strategy. In terms of mechanical properties, by optimizing the process, the tensile strength of the tensile specimens has reached 268 MPa, which is 89% of the tensile strength of the substrate. Besides, the fracture location of the specimen was not along the interface between the deposition area and the substrate, but in the overlapping area between the deposition tracks.