Effect of Single Loading Time to the Cyclic Ablation of C/C-SiC-ZrC Composite.

To understand the influence of single loading time on the cyclic ablation of carbide modified C/C composites, a C/C-SiC-ZrC composite was impacted by plasma at 2600 K for 50 s under reciprocating 0.5 (C) and 5 s (C), respectively. The composites displayed similar negative mass and rising positive linear ablation rates from C to C. Phases, micro-morphologies, and surface temperature analysis suggested that the partially oxidized SiC-ZrC covering on the ablated sample cracked and was persistently peeled off. The mass gain resulted from the ceramic's protection of the nearby carbon from complete oxidation. The longer single loading of 5 s caused strengthened thermal chemical reaction and mechanical erosion, which resulted in the bigger linear loss.