Abstract
In order to investigate the influence of oxygen on silicon carbide (SiC) ablation, ablation experiments of SiC were performed in nitrogen plasma freejets, and the results were compared with those in air plasma freejets. Weight losses and weight loss rates of SiC test piece were measured, and the test piece under heating was observed during the experiment by video camera. After heating, the surface of ablated test pieces was observed too. Some interesting differences were found clearly between the ablations in air and nitrogen plasma freejets, that is, in weight loss and weight loss rate, in shape change of a test piece, in attachment of chemical compound on the test-piece surface, and so on. It was found that these differences were mostly explainable based on the fact that the flow pattern and therefore temperature pattern around a test piece will change, depending on whether chemical compound deposits abundantly on a test-piece surface as ablations in air plasma freejets or not.
