Coatings for High Temperature, Extreme Environments

This presentation reviews the role of coating technologies for the protection of hot section components within gas turbines and explores the challenges facing surface engineers when designing coating systems for extreme high temperature service. Both thermal barrier and environmental protection coatings for conventionally cast and single crystal alloys will be considered, plus the future need for environmental barriers on advanced SiC/SiC composite materials.

With the drive for more efficient engines, reduced CO₂ emissions and the potential use of alternative fuels, engine operating temperatures are expected to increase.  Under these conditions, the engine’s performance, serviceablity and lifetime now depend on these coating systems- the coatings are prime reliant. As a result, a detailed understanding of possible failure mechanisms is required to better understand service life and the success of these coated components in service.  Potential failure mechanisms and their implication on service life will be reviewed.

• The National High Temperature Surface Engineering Centre, an Associate Member of the Henry Royce Institute, designs and tests surface treatments for components subjected to extreme and hostile environments. The Centre is the sole university provider of electron-beam physical vapour deposition (EB-PVD) thermal barrier coatings to Rolls-Royce gas turbine engines leading to significant fuel savings and reduced CO2 emissions for aviation.