Characteristics of Thermally Sprayed Alumina-Titania Ceramic Coatings obtained from Conventional and Nanostructured Powders-A Review

Alumina-titania thick coatings with finely layered microstructure are usually deposited using Air Plasma Spraying (APS) process. In the APS process, nitrogen or argon is used as the primary plasma gas. Microstructural characteristics of alumina-titania coatings are typically affected by the percentage of Titania (TiO2) present in the coatings. On the other hand, coatings obtained from nanostructured agglomerated alumina-titania powders have shown superior wear resistance over the corresponding conventional coatings. The properties of conventional Alumina-Titania coatings can also be modified by reinforcing them with some fillers like graphene, Carbon Nanotubes (CNTs), etc. From the past decade, significant research work has been in progress both industrial and academia side and still there is a lot of scope for future research on this process. This detailed review gives an overall view of Alumina-Titania coatings including their significance, microstructural, mechanical, wear, corrosion behavior and the effect of various reinforcements on their characteristics.