Fabrication of thermal barrier coatings onto polyimide matrix composites via air plasma spray process

► Thermal barrier coatings were fabricated on polyimide composites via air plasma spray process. ► TBC coating consisted of 30 μm Al layer and 130 μm YSZ layer exhibited best thermal shock resistance. ► TBC coating system provided good thermal ablation protection for the substrate. ► Failure mechanism was ascribable to residual stress, oxidation of substrate and thermal stress.