The performance of a Thermal Barrier Coatings predominantly relies on the topcoat. The topcoat should have high hardness, high wear-resistant characteristics, high thermal coefficient of expansion, low thermal conductivity, high thermal shock resistance and must able to combat corrosion. Harmonizing ceramic with metal is a significant challenge at elevated temperature and often leads to the spallation of the coating system due to thermal mismatch. A substantial amount of research activities have been carried out either indigenously or in combination with Alumina and Zirconia ceramics and reported a mixed outcome. In pursuit of enhanced mechanical, thermal and chemical properties, a composite mixture of alumina and calcia stabilized zirconia developed and systematic experimental investigations carried out. All the experimental studies viz. characterization, roughness,micro-hardness, micro-porosity, adhesion strength, abrasive wear, corrosion, and thermal cyclic tests carried out as per ASTM standards. This book covers micro to macro details related to ceramic coatings (alumina and calcia stabilized zirconia) and helps novice and professionals to understand in great detail.