Ablation behavior of three-dimensional braided C/SiC composites by oxyacetylene torch under different environments

SiC ceramic matrix composites reinforced by three-dimensional braided carbon fibers were prepared via polycarbosilane infiltration pyrolysis (PIP). The ablation behavior of the composites was characterized by an oxyacetylene torch under different environments. The morphology and microstructure of the as-ablated composites were examined by scanning electron microscopy and the composition of the new phase was confirmed by energy dispersive spectroscopy. Two conditions showed different ablation mechanisms. The erosion mechanism of the high speed oxyacetylene torch was the main ablation behavior under oxygen free environment. Thermo-chemicals ablation was the main ablation behavior under abundant oxygen environment.