Linear reciprocating wear of yttria-stabilized zirconia-based composite coatings developed by thermal spray

Ceramic matrix composites are the preferred material for high-temperature application due to their low density, improved strength and toughness, and high-temperature capabilities. In the present study, we report the kinetics and mechanism of linear reciprocating wear of yttria-stabilized zirconia (YSZ)-based composite coatings developed by thermal spray technique. Composite coatings with different volume fractions of CoNiCrAlY and YSZ phases were subjected to linear reciprocating wear under an applied normal load of 10 N against a WC counter-body. The kinetics of wear was investigated by measuring the wear depth over time of coated components against WC surface. Adhesive wear in the 100% CoNiCrAlY coating was responsible for increased friction in the coating which changed to a three-body abrasion in the case of 100% YSZ coating. The composition coatings had a significant effect on the wear mechanism with the ceramic coatings were fractured under reciprocating load. Microcrack propagation and fracturing of ceramic splats were the dominant modes of wear in the ceramic coatings. The 100% YSZ coating showed significant wear than 100% CoNiCrAlY and 50% YSZ + 50% CoNiCrAlY coatings. The mode of wear changed with the presence of a metallic phase in the 50% YSZ + 50% CoNiCrAlY coating. The mode of wear was further studied by the detailed microstructural observation of worn track and correlating it with the wear kinetics and coefficient of friction.