Property enhancement of cold sprayed Al-diamond MMC coating by using core-shelled diamond reinforcements

Abstract

Super wear-resistance and light-weight Al-based metal matrix composite (MMC) coatings were produced using cold spray. Cu-Ni coated diamond with core-shell structure and pure diamond were used as reinforcing particles, respectively. The experimental results indicate that the metallic Cu-Ni shell as a ‘buffer layer’ effectively prevented the fracture of the diamond core upon impact, while the pure diamond suffered from severe fracture during cold spray deposition. The Cu-Ni coated diamond particles were found to be much easier to deposit than pure diamond particle due to formation of metallurgical bonding between the Cu shell and Al matrix which facilitates the deposition of Cu-Ni coated diamond particles. The tribological study indicates that both diamond reinforced MMC coatings exhibited super wear resistance performance. The coating reinforced with Cu-Ni coated diamond had better wear resistance performance than the one reinforced with pure diamond due to the higher diamond content and involvement of Cu and Ni.