Wear Behaviors of Arc-Sprayed FeBSiNb Amorphous Coatings

The tribological properties of arc-sprayed FeBSiNb amorphous coatings sliding against Si3N4 under dry friction were investigated on a wheel-on-block tri-bometer. The wear mechanisms of the coating were studied based on the calculated flash temperature. Compared with the traditional mild steel, the coatings showed a higher wear resistance. The wear loss was dependent on the sliding speed and applied load. The dominating wear mechanisms of the coatings were a combination of delamination failure coupled with oxidative wear. The oxidation process is governed by the contact flash temperature of the frictional surface. The calculated flash temperature on the asperity of the amorphous coatings exceeded the glass transition temperature under dry sliding at load of 500 N. The high flash temperature led to devitrification accompanied with viscous flow and material transfer, which is responsible for the poor wear resistance of the amorphous coatings.