Effect of laser remelting on microstructure in stainless steel 17-4 PH fabricated by laser powder bed fusion

The impact of laser remelting on the microstructural evolution and associated hardening in 17-4 PH stainless steel fabricated via laser powder bed fusion was studied. Samples were prepared by a selected range of laser remelting parameters, including power, scanning speed, and remelting delay time. Variations in density, microstructure, and hardness were characterized across the prepared samples. The results showed that laser remelting can significantly alter the microstructure and enable in-situ hardening, with the degree of hardening being highly sensitive to the remelting parameters. The findings offer valuable insights into the potential of laser remelting as an in-situ microstructure engineering strategy for additively manufactured 17-4 PH stainless steel.