Thermal barrier coating for carbon fiber-reinforced composite materials

Abstract

Carbon fiber-reinforced plastic (CFRP) composites are widely employed in lightweight and high performance applications including supercars, aero-vehicles, and space components. However, although carbon fibers are thermally stable, the low thermal endurance of the matrix materials remains a critical problem in terms of the performance of the material. In this study, we proposed a new, Al2O3-based thermal barrier coating (TBC) for the CFRP composites. The TBC comprised alpha-phase Al2O3 particles with a mean diameter of 9.27 mu m. The strong adhesion between the TBC and the CFRP substrate was evaluated using a three-point bending test. When the CFRP substrate was subjected to a 500-700 degrees C flame, the 1.45-mm thick TBC protected the CFRP substrate remarkably by reducing the surface temperature to 188-228 degrees C. The thermo-mechanical responses of this TBC/CFRP composite were analyzed after thermal shock tests. Surprisingly, 50% of the pristine flexural strength of the TBC/CFRP composite was preserved, whereas that of neat CFRP was reduced significantly by 95%.