Role of Spray System and Powder Feedstock on the Sliding Wear Behaviour of WC-Co HVOF Sprayed Coatings

This paper examines the effect of spraying conditions and WC grain size on the wear behavior of WC-Co coatings. Two powders, one with a fine grain fraction and one with a more conventional grain fraction, were applied using liquid and gas HVOF systems. All coatings were subjected to sliding wear tests against an aluminum oxide ball. A sintered WC-Co composite was also tested for comparison. The sintered composite structure (cermet) exhibited the highest wear resistance, while the conventional powder sprayed by means of a gas-operated burner produced the best coating. Paper includes a German-language abstract.