Fatigue effect of WC coatings thermal sprayed by HVOF and laser treated, on medium carbon steel

Tungsten carbide coatings thermal sprayed by High Velocity Oxy-Fuel (HVOF) could be employed to obtain very hard surfaces and for the recovery of shafts or pieces with worn zones, like bearing supports, retaining rings, and so on. The aim of this study is to analyse the effects of fatigue in the WC thin coatings (about 0.1 mm thick) sprayed by HVOF on medium carbon steel substrate.Rotational bending fatigue tests were carried out with test specimens, having applied the coating over the raw materials (without anchorage layer), and the different resistance to fatigue was analysed on the uncoated material, laser surface hardened samples, the samples with the WC coating thermal sprayed by HVOF and last with the same WC coating treated by laser. Results show the possibility of predicting the fatigue life of materials with this coating and these treatments and the huge differences between them.