炭/炭复合材料ZrB2改性硅基复合涂层的高温抗氧化性能

摘要

To improve the anti-oxidation ability of silicon-based coating for carbon/carbon (C/C) composites at high temperatures, a ZrB2 modified silicon-based multilayer oxidation protective coating was prepared by pack cementation. The phase composition, microstructure and oxidation resistance at 1773, 1873 and 1953 K in air were investigated. The prepared coating exhibits dense structure and good oxidation protective ability. Due to the formation of stable ZrSiO4−SiO2 compound, the coating can effectively protect C/C composites from oxidation at 1773 K for more than 550 h. The anti-oxidation performance decreases with the increase of oxidation temperature. The mass loss of coated sample is 2.44% after oxidation at 1953 K for 50 h, which is attributed to the decomposition of ZrSiO4 and the volatilization of SiO2 protection layer.%　　为提高硅基涂层的高温抗氧化性能，采用包埋法在炭/炭(C/C)复合材料表面制备ZrB2改性硅基涂层，研究涂层的相组成、微观形貌及其在1773、1873和1953 K时的抗氧化性能。所制备的涂层结构致密，具有良好的抗氧化性能。在1773 K下形成的稳定的ZrSiO4–SiO2氧化保护膜对C/C复合材料提供550 h的氧化保护。涂层试样的抗氧化性能随温度的提高而降低，在1953 K下氧化50 h其质量损失为2.44%，这主要归因于ZrSiO4的高温分解和SiO2保护膜随温度升高的挥发。