Ablation of Al2O3f/Al2O3 Composites Under Oxyacetylene Torch Flame

Abstract Continuous alumina fibers reinforced alumina matrix composites (Al2O3f/Al2O3 composites) were produced by following the sol-gel process effectively, while the ablation behavior was analyzed and compared by means of oxyacetylene torch flame test. The results suggested that Al2O3f/Al2O3 composites showed excellent ablation resistance, but no obvious cracks, pits or holes after ablation. The mass and thickness of the sample were barely changed after ablation. After ablation for 120s at 1800℃, the surface morphology of composite material showed no significant change. With the increase of ablation temperature, there were visible signs of high-temperature and high-pressure gas erosion found on the surface of composites. Then, the molten black material began to appear on the surface, and the delamination phenomenon occurred finally. After ablation at 2200℃, the surface of composites became uneven, manifesting large-scale black molten particles, and the area affected by ablation was increasing obvious.