Optimization of Operation Frequency in the Evaluation of TBCs Using Microwave Technique

Abstract:

Thermal barrier coatings (TBCs) were developed to increase the operating temperatures of turbine blades in gas turbine engines. Non-contact inspection and the ability to penetrate into dielectric materials are two of the most important attributes of microwave non-destructive evaluation (NDE) and make it suitable for the non-destructive inspection of TBCs. In order to improve the detection sensitivity, it is important to optimize operation frequency. Computer simulation technology-microwave studio (CST-MWS) was used to optimize operation frequency in the evaluation of the top coating (TC) porosity and the metal substrate surface defects using microwave NDE. The results showed that the sensitive frequency is different when the TC thickness of under detection changes. So, it is necessary to choose appropriate operation frequency according to TC thickness to evaluate TBCs using microwave NDE.

• Periodical: Advanced Materials Research (Volumes 989-994)
• Pages: 3344-3348
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.989-994.3344
• Online since: July 2014
• Authors: Yu E Yang*, Gai Mei Zhang
• Keywords: Microwave NDE, Operation Frequency, Optimization, Thermal Barrier Coating (TBC)

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