Abstract
Nanostructured and conventional ZrO2 coatings were deposited by plasma spraying. The wear and friction properties of these coatings against stainless steel under dry and water lubricated conditions were comparatively studied respectively. The results obtained showed that the wear resistance of the coating produced using the nanostructured zirconia powder is greatly improved compared with the coating produced using the conventional powder. The wear rates of the nanostructured zirconia coatings are two-fifths and half of those of conventional zirconia coating under dry and water lubricated conditions. It is explained in terms of the optimization of microstructure and higher microhardness of the nanostructured coating. In comparison with the dry condition, the water lubrication improved the tribological properties of both nanostructured and conventional zirconia coatings, which could be attributed to the formation of a smooth surface mainly consisting of zirconia and Fe3O4.