Microwave Drilling of Ceramic Thermal‐Barrier Coatings

Abstract

The microwave drill is a novel process for creating shaped holes in nonconductive materials. Its inherent material selectivity makes the microwave drill ideally suited for the controlled removal of ceramic coatings from underlying metallic substrates. In this paper, it is shown that the microwave drill process can drill through ceramic thermal barrier coatings (TBCs) to uncover an array of simulated cooling holes. The concept, apparatus, and procedure for successful drilling are described, and the potential for use in the production of advanced gas turbine components is discussed.