Optimization of Process Parameters for Plasma Sprayed Lanthanum Zirconate TBCs on Nickel Based Superalloy

Abstract

Thermal Barrier Coating are highly advanced material systems usually applied to metallic surfaces, such as gas turbine or aero-engine parts, operating at elevated temperatures. They have ceramic and metallic multilayers which have been widely used in the aeroturbine engines to increase the life of metallic components and turbine efficiency. Many different types of coatings are used to protect variety of engineering materials from wear, corrosion and erosion. Of all these, TBC’s play a vital role in providing thermal insulation and protect the material from high temperature environment. In this paper Lanthanum Zirconate (La2Zr2O7) is used as a coating material which is phase-stable to its melting point, Lanthanum Zirconate is a promising material which exhibit lower thermal conductivity and higher thermal stability compared to other TBC system. High quality Lanthanum Zirconate based TBC is developed by plasma spray technique on superalloys. In the present investigation porosity, microstructure, hardness and bond strength of the developed TBC’s were characterized and significant parameters of plasma spray process were identified.