Achieving significant enhancement in the strength-plasticity performance of TiC/316L via laser remelting-induced secondary precipitation of nano-TiC

A significant strengthening of 316L was achieved by adding TiC particles using the Selective Laser Melting (SLM) process, but it still faced challenges such as compromised plasticity. Laser remelting, as an effective post-processing technique for enhancing the performance of components fabricated by SLM, demonstrated significant potential in improving surface quality and optimizing microstructure. Accordingly, this study introduced laser remelting with varying scan speeds based on the SLM of 3% TiC/316L composites, aiming to investigate the regulating mechanism of this process on the surface morphology, microstructure, and mechanical properties. The results indicated that the laser remelting at 1000 mm/s remelting scanning speed significantly reduced the surface roughness and internal defects; its average microhardness value increased to 380 HV; both strength and elongation surpassed the 316L matrix, achieving a synergistic improvement in strength and ductility. This study demonstrated that the optimized laser remelting strategy provided an effective route for the synergistic enhancement of both the microstructure and properties of TiC/316L composites fabricated by SLM.