Processing and design methodologies for advanced and novel thermal barrier coatings for engineering applications

Thermal barrier coating is a crucial thermal insulation technology that enables the underlying substrate to operate near or above its melting temperature. Such coatings bolster engineers' perpetual desire to increase the power and efficiency of gas turbine engines through increasing the turbine inlet temperature. Advances in recent years have made them suitable for wider engineering and defense applications, and hence they are currently attracting considerable attention. A thermal barrier coating system is itself dynamic; its components undergo recurrent changes in their composition, microstructure and crystalline phases during its service life. Nevertheless, the performance of multi-layered and multi-material systems tailored for high temperature applications is closely linked to the deposition process. The process improvements achieved so far are the outcome of increased understanding of the relationship between the coating morphology and the operating service conditions, as well as developments in characterization techniques. This article presents a comprehensive review of various processing techniques and design methodologies for thermal barrier coatings. The emphasis of this review is on the particle technology; the interrelationship between particle preparation, modification and the resulting properties, to assist developments in advanced and novel thermal barrier coatings for engineering applications. (C) 2016 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.