Wear of plasma-sprayed nanostructured zirconia coatings against stainless steel under distilled-water conditions

The friction and wear properties of plasma-sprayed nanostructured and traditional zirconia coatings against stainless steel were investigated with a sliding, reciprocating and vibrating test machine under water-lubricated conditions. The counterface was a 10-mm diameter AISI316 stainless steel ball. It was found that the plasma-sprayed nanostructured zirconia coating possessed better wear resistance than traditional zirconia coating. The wear rates of the nanostructured zirconia coatings are in the range from one-fourth to four-fifths of the traditional zirconia coating under loads ranging from 20 to 50 N. The plasma-sprayed nanostructured zirconia coating also reduces wear rate of the friction pair materials. The higher wear resistance of the plasma-sprayed nanostructured zirconia coating is attributed to its enhanced cohesion, improved microhardness and homogenous microstructure. The wear mechanisms of nanostructured and traditional zirconia coatings under water-lubricated conditions are discussed. (C) 2003 Elsevier Science B.V. All rights reserved.