Experimental and Numerical Investigations of TBC Behaviour after Aging, Subjected to Tension and Bending

Abstract

Thermal Barrier Coatings (TBCs) have been extensively used in aircraft engines to improve durability and performance. They protect critical engine parts such as blades and combustion chambers, which are exposed to high temperatures and corrosive environment.Testing of coated metallic alloys, subjected to ageing process, allows determination of the TBCs properties. In this paper we performed 2 tests: uniaxial tension and bending. The aging of samples was carried out in 1000°C for times: 48h, 89h, 185h and 353h. Thermally Grown Oxide (TGO) layer thickness (SEM observations) and the strain level corresponding to damage of the TBCs were determined experimentally.The experimental results were used to build numerical model in Abaqus program. Brittle cracking damage model was applied to describe of the TBC layer degradation. Surface based cohesive behavior was used to model delamination of the interface between a bond coat (BC) and a top coat (TC).The proposed numerical model describes with high accuracy experimental results.