Fabrication and thermal shock resistance of in situ SiC nanowire-SiC/SiC coating for carbon/carbon composites

Abstract

To improve toughness of SiC outer layer produced by chemical vapour deposition for carbon/carbon composites, in situ SiC nanowires on SiC inner layer were prepared by pack cementation. SiC nanowires were distributed uniformly on SiC inner layer, and SiC was filled in the interspace of SiC nanowires to form a dense SiC outer layer. After introducing SiC nanowires, the size of cracks in SiC outer layer decreased and the weight loss of coated carbon/carbon samples decreased from 127.7gm−2 to 76.2gm−2 after 40times thermal cycling between 1773K and room temperature.