Oxidation experiments were conducted with several experimental mechanical carbons at 650℃ in air flowing at 28 cu cm/sec (STP). Experiments indicate that boron carbide addition and zinc phosphate treatment definitely improved oxidation resistance. Impregnation with coal tar pitch before final graphitizatión had some beneficial effect on oxidation resistance and it markedly improved flexure strength and hardness. Graphitization temperature alone did not affect oxida¬tion resistance, but with enough added boron carbide the oxidation resistance was increased although the hardness greatly decreased.
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