Abstract:

Material performance in many industrial applications is strongly affected by the behavior of the surfaces. For example, corrosion response reactivity with environments, wear characteristics, and thermal properties are all critically dependent on surface character. Utilization of coatings to upgrade component performances is often a cost effective alternative to substitution of superior bulk materials. The advantage of coating technology, in general is that it marries two dissimilar materials to improve the performance of the whole. The coatings comprised of zirconia top coat and nickel-aluminum bond coat. Ni - 5wt % Al (bond coat) and ZrO2 - 20wt % Mg O. (top coat) have been deposited on the super alloy Ni Cr 20 Ti Al. by using by A.P.S technique. The main focus of this work is to study the surface microstructure, mechanical characteristic, and thermo-physical properties as well as their properties with those obtained using reference techniques. Thermal expansion studies were used to study the high temperature stability of the different coatings structures. As low thermal conductivity is one of the most important features of TBC, thermal diffusivity and specific heat measurements were carried out. Also the mechanical measurements (e.g. micro-hardness and tensile bond strength).