Wear Resistance of Electroless Ni-P-MoS₂ Coating on TC4 Titanium Alloy

In this paper, TC4 titanium alloy was used as substrate,and electroless Ni-P-MoS₂ composite coatings were obtained successfully on its surface. The influences of pH, MoS₂ concentration on the composite coating were discussed. Furthermore, the coating morphology after the wear test was observed. The results show that the wear resistance of composite coating increased first and then decreased with the increase of MoS₂ particles concentration in the bath and pH. When the MoS₂ concentration is 2g/L and the pH is 6.0, the combined action of cationic surfactant-hexadecyl trimethyl ammonium bromide(CTMAB) and anionic surfactant-sodium dodecyl sulfate(SDS) can promote the co-deposition of MoS₂ particles and Ni-P alloy and the formation of uniform solid lubricating film on titanium alloy surface, therefore leading to the marked decrease of friction coefficient. MoS₂ particles can bring good solid self lubricating effect on the surface of coating and lessen the occurrence of the adhesive wear.