Investigation of competing failure mechanism and life of plasma sprayed Fe-based alloy coating under rolling-sliding contact condition

The paper aims at the investigation of the effect of slip ratio on the rolling contact fatigue (RCF) performance of Fe-based alloy coatings. A double-roll test machine is employed to perform the experiment. The result shows that slip ratio has a significant influence on the RCF performance of Fe-based coating. With the increment of the slip ratio, the RCF failure life keeps decreasing but the shape parameter β of Weibull mode decreases first, then increases. The failure mechanism under pure rolling contact condition is the accumulation of micro-pits and the propagation of fatigue cracks within the coating. However, under nonzero slip ratio condition, failure is controlled by the coupling of the cyclic loading action and of the friction force.