Wear properties of CrC–37WC–18M coatings deposited by HVOF and HVAF spraying processes

CrC–37WC–18M cermet coatings were deposited using new feedstock powders which seem to combine the properties of WC–CoCr and CrC–NiCr coatings. A conventional particle size CrC–37WC–18M powder was used as feedstock for the HVOF (high velocity oxygen fuel) thermal spraying process and a fine particle distribution was used as feedstock for the HVAF (high velocity air fuel) thermal spraying process. In order to characterize the morphology of the feedstock powders and deposited coatings SEM and X-ray diffraction were used. The microhardness of the coatings was also studied. The wear behavior of the coatings was evaluated by pin-on-disk and rubber wheel abrasion tests. The HVAF coating showed equal or even better wear resistance as compared to corresponding HVOF coatings.

► Comparison between HVOF and HVAF sprayed CrC–37WC–18M cermet coatings
► HVOF coating presented oxides and new and different phases in comparison with the feedstock powder.
► HVAF coating presented no oxides and no significant phase transformation during spraying occurred.
► HVAF deposited coating has comparable abrasion and sliding wear resistance to HVOF deposited coating.