NDE of Gas Turbine Thermal Barrier Coatings

Thermal barrier coatings are increasingly being used to protect metal components from the hot gas stream in advanced industrial gas turbines. Their use improves the durability of turbine parts and increases efficiency of operation. However, premature failure remains a critical concern. Thus, it is very important to have a non-destructive evaluation technique for quality control and to detect early damage of thermal barrier coatings during use. Current inspection methods are either destructive or do not provide sufficient evaluation of the coating. This project will develop an optical, nondestructive inspection method for thermal barrier coatings. The method will provide unprecedented imaging of the thermal barrier coating layers and structure, and will be capable of detecting damaged coatings and conditions indicative of degradation of the coating. Commercial Applications and other Benefits as described by the awardee The NDE inspection method should enable better quality control inspection of thermal barrier coated turbine parts at manufacturing and maintenance facilities, allow coatings that are close to failure to be identified, and lead to better methods for predicting the useful life of coated parts. In turn, such capabilities would lead to cost savings for turbine parts manufacturers, since destructive testing for quality control will be eliminated. Substantial savings for power plant operations should accrue ¿ unplanned shutdowns are extremely costly to the power industry and its customers.