One-step preparation of high performance Ni-MoS 2 self-lubricating coatings via jet electrodeposition on additive manufactured aluminum alloy

Abstract

Composite coatings with solid lubricants can improve the tribological performance of aluminum alloy parts prepared by Laser Powder Bed Fusion (LPBF). In this study, Ni-MoS₂ self-lubricating composite coatings were one-step prepared on additive manufactured aluminum alloy surface via jet electrodeposition. The properties and lubrication performance of the coatings prepared using composite electrolyte with different MoS₂ particle diameters and concentrations were investigated. The lubrication mechanism of the composite coating was discussed. The results showed that 0.8 μm MoS₂ had less agglomeration than 80 nm, resulting in a uniform surface. The lubrication performance of the composite coating was affected by MoS₂ particles content and coating hardness. With the increase of MoS₂ concentration in the composite electrolyte, the friction coefficient and wear rate decreased, and achieved the best lubrication performance of 0.12 friction coefficient and 0.11 mg/m wear rate when MoS₂ composite electrolyte is 5 g/l and MoS₂ is 0.8 μm. However, the addition of soft MoS₂ decreased the coating hardness, lower hardness will cause lubrication failure.