ZrB2-MoSi2/SiC涂层C/C复合材料的制备及氧化性能

摘要

To improve the oxidation resistance of carbon/carbon composites,ZrB2-MoSi2/SiC coating on the carbon/carbon substrate was prepared.The inner coating of SiC was prepared by pack cementation and the outer coating of ZrB2-MoSi2 was prepared by slurry painting.The phase compositions and microstructures of the coating were characterized by XRD and SEM,respectively.The preparation and the high temperature oxidation property of the coated composites were investigated.The results show that the outer coating of carbon/carbon composites is composed of ZrB2,MoSi2 and SiC phases.The mass losses of the ZrB2-MoSi2/SiC coated samples with SiC nano-whiskers after 30 h and 10 h of oxidation at 1 273 K and 1 773 K were,respectively,5.3％ and 3.0％.The ZrB2-MoSi2/SiC coated samples exhibit self-sealing performance and good oxidation resistance at high temperature.%为了提高C/C复合材料的抗氧化性,在C/C复合材料基体上制备了ZrB2-MoSi2/SiC涂层.采用包埋法制备SiC中间层,采用喷涂法制备ZrB2-MoSi2外涂层.用XRD和SEM分别分析、测试所制备涂层的物相组成和显微结构,研究涂层复合材料的高温抗氧化性能.结果表明:C/C复合材料的外涂层由ZrB2、MoSi2和SiC三相组成；在1 273K和1 773K下分别氧化30 h和10h后ZrB2-MoSi2/SiC涂层试样的质量损失分别为5.3％和3.0％,涂层表面长有纳米SiC晶须.C/C复合材料ZrB2-MoSi2/SiC涂层具有自愈合特性和良好的高温抗氧化性能.