Effect of the microstructure of EB-PVD thermal barrier coatings on the thermal conductivity and the methods to reduce the thermal conductivity

Purpose: The goal of the paper is to evaluate the effect of the microstructure of EB-PVD thermal barrier coatings on the thermal conductivity and the methods to reduce the thermal conductivity. Design/methodology/approach: In this study, the effect of microstructure of the coating to the thermal conductivity of EB-PVD TBCs and the methods to reduce the thermal conductivity of these coatings have been investigated. Findings: Microstructure of the EB-PVD coating - it is found that they are formed in two different structure and microstructural characteristics and they are different from each other. Practical implications: Nowadays, selection of materials for usage purpose is getting important because of new high technologic developments. Especially for the parts operating at high temperatures, materials which have low thermal conductivity and high mechanical resistance are preferred. Thermal Barrier Coatings (TBCs) are used in aerospace, diesel engine and power plant technologies due to porous structures and low thermal conductivity. Generally these coatings are applied by two methods, Electron Beam-Plasma Vapour Deposition (EB-PVD) and Atmospheric Plasma Spray (APS). Originality/value: This paper reviews the current status of EB-PVD thermal barrier coatings technology and investigation to reduce the thermal conductivity in future generations of EB-PVD thermal barrier coatings.