Ablation behavior of sharp leading edge parts made of rare earth La-compound modified ZrB2 coated C/C composites

LaB6-ZrB2 and La2O3-ZrB2 coating were prepared on the sharp leading edge shaped C/C composites by supersonic atmosphere plasma spraying and their oxyacetylene ablation behavior were investigated. Results indicated that the oxide scale generated after ablation of LaB6-ZrB2 coating presented porous due to the excess B content, which decreased the compactness. For La2O3-ZrB2 coating, La2O3 dissolved into ZrO2 by diffusion, forming a dense oxide scale containing La0.1Zr0.9O1.95, which offered the best ablation protection. Moreover, the analysis of La2O3-ZrB2 coating in combination with computational fluid dynamics simulation revealed the ablation behavior of different areas.