Characterization and friction-reduction performances of composite coating produced by laser cladding and ion sulfurizing

• A novel composite coating was produced by laser cladding and ion sulfurization.
• A micro–nano sulfide solid lubrication film was successfully prepared on the surface of Ni-based alloy deposited coating.
• The surfaces of sulfurizing layers are loose and uneven.
• The sulfurizing layers are well bonded with laser cladding coating.
• The friction coefficient and wear loss of sulfurizing composite coating decrease apparently under dry and oil lubrication condition.

The microstructure and friction-reducing performance of a novel composite coating produced by laser cladding and ion sulfurization was investigated in this paper. It can be seen that a micro–nano sulfide solid lubrication film of about 3–4 μm thickness was successfully prepared on the surface of Ni-based alloy deposited coating. The surfaces of sulfurizing layers are loose and uneven, and the sulfurizing layers are well bonded with the laser cladding layer. The result of friction and wear test indicates that the friction coefficient and wear loss of sulfurizing composite coating decrease apparently under dry and oil lubrication condition. The sulfurizing layer of FeS and WS2 phase on the hard Ni-based alloy layer played an important, beneficial role for improving the friction-reducing performance of laser cladding coating.