What is thermal barrier coating (TBC)?

A thermal barrier coating (TBC) is specifically designed as a ceramic layer that serves to reduce heat transfer between the hot gas path and the underlying metal components of a gas turbine engine. This reduction in heat transfer helps to protect the metal substrates from extreme temperatures, allowing them to operate at higher temperatures while maintaining structural integrity and performance.

The primary function of TBCs is to provide thermal insulation; they allow the engine to achieve higher efficiency and power output by enabling the use of hotter combustion temperatures. The ceramic materials used in TBCs have low thermal conductivity, which is crucial for minimizing heat transfer to the engine components, thereby extending their life and reducing the frequency of maintenance.

Furthermore, TBCs also play a role in improving overall fuel efficiency and performance, but their main purpose is focused on thermal management rather than enhancing fuel efficiency directly. Therefore, while thermal barrier coatings can indirectly contribute to improved performance qualities, their defining characteristic is their ability to act as a thermal insulator.