Thermal cycling behavior and oxidation resistance of SiC whisker-toughened-mullite/SiC coated carbon/carbon composites in burner rig tests. (May 2016) - ZhongLiu, Wen
Highlights: A SiC whisker-toughened mullite coating was successfully fabricated on SiC-coated carbon/carbon composites by sol–gel process. The oxidation resistance and thermal cycling durability of coated sample was investigated in a cyclic jet fuel burner rig operated at a temperature of 1450 ± 55 °C. Oxidation and thermal cycling resistance of the mullite outer coating improved significantly upon the incorporation of the SiC whisker. The toughening mechanisms of SiC whisker were mainly attributed to whisker bridging and crack deflection. Abstract: An oxidation protective SiC whisker-toughened mullite coating was prepared on SiC coated carbon/carbon (C/C) composites by a novel sol–gel technique. The thermal cycling and oxidation behavior of the coated C/C coupons was investigated by thermally cycling between room temperature and 1450 ± 55 °C on a jet fuel burner rig facility. Results show that incorporating proper amounts of SiC whiskers can significantly improve the thermal cycling resistance of the mullite coating due to the energy dissipation mechanism induced by the whisker bridging and crack deflection.