Thermal property evolution of metal based thermal barrier coatings with heat treatments

Predicting "in-service" lifetime of ceramic thermal barrier coatings (TBCs) is difficult due to the inherent brittle nature of ceramics used. Therefore, the study of metal-based thermal barrier coatings (MBTBCs) has been initiated to challenge the current problems of ceramic-based TBCs (CBTBCs) and create a new generation of thermal barrier coatings (TBCs). In this work, nano/amorphous structured MBTBCs, for use in internal combustion engines, have been produced using high frequency induction plasma spraying (IPS) of iron-based nanostructured alloy powders. Coatings were deposited by IPS using various spray parameters and heat treated up to 850 degrees C to study the thermal stability of the coating. The thermal diffusivity (alpha) properties of MBTBCs were measured using a laser flash method. Density (rho) and specific heat (C-p ) of the MBTBCs were also measured for calculating thermal conductivity (k = alpha rho C-p).