| Abstract Scope |
Cold spray deposition of 316L stainless steel often produces porous coatings due to limited particle deformation and weak inter-particle bonding, leading to inferior mechanical performance compared to wrought 316L steel. While post-treatments such as annealing, HIP, and laser remelting enhance bonding and reduce porosity, they increase cost and complexity, limiting scalability. In-situ densification with foreign shot-peening media improves deposit properties but risks contamination and material incompatibility. This study presents a new in-situ self-peening approach where 316L powder is used as both the deposit and peening media. Mechanical milling is used to enhance the hardness and size of the peening powder, which is then blended with gas-atomized powder for cold spray deposition. This technique markedly improves particle deformation and metallurgical bonding, yielding deposits with lower porosity, higher hardness, and improved strength. The proposed self-peening approach offers a contamination-free, scalable solution for dense, high-integrity 316L coatings, eliminating the need for extensive post-processing. |