National Research Council of Canada. Automotive and Surface Transportation
cold spray; Cu-MoS2 composite; fretting; normal load; wear debris bed
Cu and Cu-MoS2 coatings were fabricated by cold spray, and the fretting wear performance of the two coatings was compared. A mixture (95 wt.% Cu + 5 wt.% MoS2) was used as feedstock for the composite coating. Coatings were sprayed with identical gas flow conditions on the substrates pre-heated to approximately 170 °C. The morphology of coating top surface and polished cross sections was analyzed by scanning electron microscopy (SEM) and light optical microscopy (LOM). The influence of MoS2 on Cu deposition was examined. The local MoS2 concentration within the coating was found to affect the hardness. Fretting tests were carried out at two different normal loads, and the influence of MoS2 on friction and wear was studied. The morphology and elemental compositions of the wear scars and wear debris were observed by SEM and energy dispersive x-ray spectroscopy (EDS), respectively.