Stress rupture behavior of a thermal barrier coated AE 437A Ni-based superalloy used for aero turbine blades

The stress rupture characteristics of bare and thermal barrier coated (TBC) superalloy AE 437A were determined in air at temperatures between 600 and 850 °C with both short and long term testing undertaken at 800 °C. Because the bond coat contributed an addition 10% cross-sectional area and was able to support load, the higher stress, shorter term rupture lives of the TBC coated alloy exceed those for the bare material. However under lower stress, longer life conditions the ability of the bond coat to support loading was reduced, and the rupture lives of both bare and TBC coated alloy were similar.