Heterostructure induced excellent nanomechanical and tribological properties in selective laser melted 316L stainless steel

This study reports a promising combination of nanomechanical and tribological properties in 316L stainless steel produced through selective laser melting (SLM) by forming a heterostructure. The findings indicate that the layer-by-layer deposition and rapid solidification lead to the development of multi-directional cellular substructures. Additionally, prolonged high-temperature annealing encourages the formation of bimodal structures. The creep rate sensitivity (m) of 316L steel ranges from 0.006 to 0.014, with an activation volume ( v ∗ ) of 30–60 b 3 , suggesting that its creep behavior is dislocation-mediated. The formation of a bimodal structure raises the m value and lowers the activation volume, which implies a reduction in creep resistance. The primary wear mechanisms in 316L steel include plastic deformation, abrasive wear, fatigue wear, and oxidative wear. Although the formation of bimodal structures reduces fatigue wear and enhances the protection of the self-lubricating layer, this protection diminishes as the growth of bimodal structures. This study provides valuable insights into the industrial application of selective laser melted 316L stainless steel.