Influence of laser beam welding parameters on the microstructure and mechanical behavior of Inconel X750 superalloy

In welding, the process parameters influence the mechanical properties of the joint. However, such investigations on laser welding of Inconel X750 are lacking despite its industrial significance. We performed such an investigation in which three parameter combinations, out of seven, exhibited full laser penetration (S1 (75 mm/min, 800 W), S2 (75 mm/min, 1200 W), and S3 (150 mm/min and 1200 W)). Microstructural analysis exhibited changes in the grain and dendrite morphology with columnar to equiaxed transition from the fusion boundary to the interior. S3 exhibited superior mechanical properties than others due to the smaller grain size and fusion zone.