Effect of MoS2 mass fraction on microstructure and tribological characteristics of laser cladded Cu-10Al coating

Cu-10Al coatings with the different MoS2 mass fractions were fabricated on Q235 steel using laser cladding (LC). The surface morphologies, chemical compositions and phases of obtained coatings were analyzed using a scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), respectively. The effects of MoS2 mass fraction on the microstructure and friction and wear properties under the oil-lubrication condition were studied, and the wear mechanism was also discussed using a plane scan analysis. The results show that the laser cladded Cu-10Al coatings with the different MoS2 mass fractions were mainly composed of solid solution phases of Cu0.78Al0.22 and intermetallic compound of Cu9Al4 and AlFe3. The average coefficient of frictions (COFs) of Cu-10Al-4%MoS2, 8%MoS2 and 12%MoS2 coatings are 0.195, 0.158, and 0.124, respectively, which decease with the MoS2 mass fraction; and the corresponding wear rates are 2.54 x 10(-7), 1.29 x 10(-7), and 1.98 x 10(-7)mm(3).N-1.m(-1), respectively, the wear rate of Cu-10Al-8%MoS2 coating is the lowest among the three kinds of coating, the main wear failure mode are abrasive wear and adhesive wear.