The Influence of Powder Types and Plasma Spray Conditions on Abrasive Wear of Nanostructured and Conventional Al_2O_3/TiO_2 Coatings

摘要

In this paper, Al_2O_3/TiO_2 coatings via thermal spray approach using three different feedstock powders, i.e., (a) reconstituted nanosized Al_2O_3/TiO_2 feedstock powders, (b) reconstituted nanosized Al_2O_3/TiO_2/ZrO_2/CeO_2 feedstock powders and (c) conventional Al_2O_3/TiO_2 feedstock powders are described. Effects of different powder types and various plasma spray conditions on the density, microhardness and crack resistance, especially on the abrasive wear behavior of the coatings have been evaluated. The result showed that the coatings sprayed using different feedstock powders exhibit different abrasive wear behavior with changing the plasma spray conditions. The coatings sprayed using the reconstituted nanosized Al_2O_3/TiO_2/ZrO_2/CeO_2 feedstock powders showed a significantly improved wear resistance compared to the coatings sprayed using reconstituted nanosized Al_2O_3/TiO_2 feedstock powders or conventional Al_2O_3/TiO_2 feedstock powders. The wear mechanisms of the coatings were discussed.