Thermal Barrier Coatings—A State of the Art Review

Abstract

Thermal barrier coatings (TBCs) have seen considerable advancement since the initial testing and development of thermal spray coating. Thermal barrier coatings are currently been utilized in various engineering areas which include internal combustion engines, gas turbine blades of jet engines, pyrochemical reprocessing units and many more. The development of new materials, deposition techniques is targeted at improving the life of the underlying substrate. Hence, the performance of the coating plays a vital role in improving the life of substrate. The scope for advancement in thermal barrier coatings is very high and continuous efforts are being made to produce improved and durable coatings. Thermal barrier coatings have the potential to address long term and short-term problems in gas turbine, internal combustion and power generation industry. The study of thermal barrier coating material, performance and life estimation is a critical factor that should be understood to introduce any advancement. The present review gives an overview of the thermal spraying techniques and current advancements in materials, mechanical properties, understanding the high temperature performance, residual stress in the coating, understanding the failure mechanisms and life prediction models for coatings.

Estimation of residual stress in air plasma sprayed MWCNT-reinforced 8YSZ–alumina composite coating

“…The CTE of NiCrAlY and steel substrate is represented as a function of temperature in Eqs. (5) and (6), respectively.…”

“…The residual stress arises as a result of quenching of these particles (primary cooling) and difference in coefficient of thermal expansion (CTE) between the powder constituents and substrate. Primary cooling introduces tensile residual stress in the coating [6]. The cooling of the substrate-coating system to room temperature is referred to as secondary cooling and results in compressive or tensile residual stress in coating.…”

Effect of ceramic‐based coatings deposited on low‐alloyed steel T/P22 10H2M exposed at high temperature

“…The coatings are called thermal barrier coatings (TBC). 8,9 Those type of coatings are used in mainly in aero jest engines and in gas turbine technologies. 10,11 The TBC are generally based on yttria-stabilized zirconia phase deposited by electron-beam physical vapor deposition (EB-PVD) or APS process.…”

“…One of the most advanced ceramic coatings produced recently are the coatings reducing the based metal temperature in Ni‐based alloy. The coatings are called thermal barrier coatings (TBC) 8,9 . Those type of coatings are used in mainly in aero jest engines and in gas turbine technologies 10,11 .…”

Interfacial Structure and Physical Properties of High-Entropy Oxide Coatings Prepared via Atmospheric Plasma Spraying

“…With the advancement of TBCs over recent decades, various methods have also been developed to synthesize new TBCs with more promising properties and applications. These methods are broadly divided into several categories, including the use of lasers, thermal spraying, vapor deposition, powder metallurgy, and chemical-based methods [35,36]. Among these, thermal spraying is the most widely used method because of its efficiency, accessibility, and practicability over a wide range of materials.…”