Stress analysis of a barb test for thermal barrier coatings

Stress distributions in a barb pullout specimen prepared from the thermal barrier coating (TBC)/substrate structure are analyzed by the finite element method. Contribution of thermal stresses and applied stresses is included in the computations. Interfacial stress singularity at the test support edge is evaluated and effects of various Young's modulus ratios between the TBC layer and substrate are shown. The results help to understand the mechanical behavior in the barb test.