Structural and Tribological Characteristics of Nanoscale FePSiBNb Coatings

摘要

The tribological properties of nanostructured FePSiBNb coating prepared by arc spraying sliding against WC ball at different loads and speeds were investigated. The coating consists of nanoscale alpha Fe structure with grain size ranging from 12 to 50 nm. The hardness and reduced elastic modulus of the coating are 12.3 and 204 GPa, respectively. The average porosity of the coating is less than 3%. The friction coefficient of the coating decreases gradually with increasing normal load. The wear rate of the coating is increasing linearly as a function of the normal load, whereas it shows an inverse trend with increasing sliding speed. The excellent wear resistance of the coating is attributed to its good mechanical properties and the formation of local tribo-oxide films on the worn surface. The dominating wear mechanism of the coating is a combination of oxidative wear coupled with delamination under dry sliding conditions.