A dense ZrB_2 particles reinforced glass(ZrB_2/SiO_2) coating was prepared on the SiC coated carbon/carbon composites by a facile sol-dipping approach. The prepared ZrB2/SiO2 coating could protect the composites from ...A dense ZrB_2 particles reinforced glass(ZrB_2/SiO_2) coating was prepared on the SiC coated carbon/carbon composites by a facile sol-dipping approach. The prepared ZrB2/SiO2 coating could protect the composites from being oxidized for 160 h at 1773 K with a weight loss of 6.9 mg/cm^2. The flexural strength retention ratio of the ZrB_2/SiO_2 coated composites is 87% after oxidation for 160 h at1773 K. The continuous SiO_2 glass layer embedded with the submicron ZrSiO_4 particles was formed during oxidation. This was helpful to lower the diffusion rate of oxygen and improve the stability of SiO_2 glass film, thus improving the oxidation resistance of the coated samples. After thermal cycles between 1773 K and room temperature for 15 times, penetrated cracks formed in the coating. The weight loss of the ZrB_2/SiO_2 coated sample presented linear relationship, and the final weight loss per unit area was 6.35 mg/cm^2. The generation of the penetrative cracks and the debonded coating interface resulted in the failure of the ZrB_2/SiO_2 coating.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 51302160 and 51402177)the Science and Technique Talent Project of Shaanxi Province (Grant No. 2016KJXX-07)+2 种基金Natural Science Foundation of Shaanxi Province (Grant No. 2018JM5038)Natural Science Foundation of Education Department of Shaanxi Province (Grant No. 14JK1103)Research Foundation of Shaanxi University of Science & Technology (Grant No. BJ14-20)
文摘A dense ZrB_2 particles reinforced glass(ZrB_2/SiO_2) coating was prepared on the SiC coated carbon/carbon composites by a facile sol-dipping approach. The prepared ZrB2/SiO2 coating could protect the composites from being oxidized for 160 h at 1773 K with a weight loss of 6.9 mg/cm^2. The flexural strength retention ratio of the ZrB_2/SiO_2 coated composites is 87% after oxidation for 160 h at1773 K. The continuous SiO_2 glass layer embedded with the submicron ZrSiO_4 particles was formed during oxidation. This was helpful to lower the diffusion rate of oxygen and improve the stability of SiO_2 glass film, thus improving the oxidation resistance of the coated samples. After thermal cycles between 1773 K and room temperature for 15 times, penetrated cracks formed in the coating. The weight loss of the ZrB_2/SiO_2 coated sample presented linear relationship, and the final weight loss per unit area was 6.35 mg/cm^2. The generation of the penetrative cracks and the debonded coating interface resulted in the failure of the ZrB_2/SiO_2 coating.
