Microstructural and mechanical properties of thermal barrier coating at 1400°C treatment

The mechanical properties of plasma-sprayed thermal barrier coating (TBC) play a vital role in governing their lifetime and performance. This work investigated the microstructural and mechanical properties of TBC with high temperature treatment at 1400°C by scanning electron microscopy and indentation. We calculated elastic modulus and hardness through the application of Weibull statistics analysis. The results indicate that the microstructure of ceramic coating will change continuously at high temperature, and accordingly the porosity decreases due to the grain growths and crack closes. In addition, the elastic modulus and hardness nonlinearly go up with the heat treatment time and go down with increasing porosity. This demonstrates that the microstructural evolution and porosity of TBC are caused by high temperature treatment, and as a result its mechanical properties are influenced.