Fatigue resistance of thermal-sprayed additively manufactured MS1 steel under varied mechanical loading conditions

Abstract This study investigates the fatigue resistance of additively manufactured MS1 steel coated with thermally sprayed WC-Cr 3 C 2 -Ni and Cr 3 C 2 -NiCr, applied using High Velocity Oxygen Fuel technology. The research focuses on evaluating the effects of these coatings on fatigue life under varying mechanical loading conditions. It was shown that such treatments greatly improve resistance to fatigue, especially at low stress levels by delaying crack initiation and slowing down their propagation. Nevertheless, when stress levels are higher, benefits from coating diminish and differences in fatigue strength between coated and uncoated specimens are unnoticeable. Under torsional loads, the coatings are rapidly damaged, which may suggest that the driving force behind wear is surface shear stress and that further improvement of the durability of coatings are necessary.