Design and preparation of multilayer TaC/HfC coating: Ablation behavior under oxyacetylene flame with different heat flux

The design of a new multilayer anti-ablation coating is inseparable from the performance assessment in multiple environments. This work investigates the effects of different ablation flux on the microstructure evolution and phase composition of multilayer TaC/HfC coating. The results show that the different temperature regions were generated on ablated coating surface, resulting in the formation of different oxidation products. At heat flux of 2.4 MW/m(2), the formation of dense Hf-Ta-O solid solution phase tightly adhered on substrate. As heat flux increased to 4.2 MW/m(2), a large amount of molten oxidation phase was produced in the central area, which caused secondary damage to the coating under the action of high-speed flame.