中文摘要：

采用溶胶-凝胶法合成了Ba0.5Sr0.5Al2Si2O8（BSAS）-Y2Si2 O7粉体,并以2D Cf/SiC为基体,采用浆料涂覆工艺在其表面制备了BSAS-Y2Si2O7环境屏障涂层,表征了涂覆与未涂覆BSAS-Y2Si2O7涂层Cf/SiC复合材料的抗水氧腐蚀性能.结果表明：在高纯氩气保护下,经1450℃高温烧结3h,可在Cf/SiC试样表面制备致密的BSAS-Y2Si2O7涂层;在1250℃、50％H2O-50％O2、常压静态气氛下腐蚀200 h后,涂覆BSAS-Y2Si2O7涂层的Cf/SiC试样的质量基本不变,基体中的纤维得到了很好的保护,所制备的BSAS-Y2Si2O7涂层具有较好的抗水氧腐蚀性能;同时,BSAS-Y2Si2O7涂层也表现出裂纹自愈合能力;与之相比,未涂覆BSAS-Y2Si2O7涂层的Cf/SiC试样的失重较为明显,基体中的纤维已经完全被水氧环境所侵蚀.

英文摘要：

Ba0.5Sr0.5Al2Si2O8（BSAS）-Y2Si2O7 powders were synthesized by the sol-gel process.The BSAS-Y2Si2O7 coatings were coated on the surface of 2D Cf/SiC composites by the slurry-brushing process as an environmental barrier.The dense BSAS-Y2Si2O7 coatings were obtained after heat-treatment at 1450 ℃ for 3 h under argon.The water-vapor corrosion resistance of the composites with and without BSAS-Y2Si2O7 coatings was tested at 1250 ℃ in 50％H2O-50％O2 environment.After water-vapor corrosion for 200 h,the Cf/SiC composites with BSAS-Y2Si2O7 coatings show a little of weight change.The C fibers in the composites are protected very well by the BSAS-Y2Si2O7coatings.In the BSAS-Y2Si2O7 coatings,the cracks were healable after water-vapor corrosion for 200 h.As comparison,the composites without BSAS-Y2Si2O7 coatings show a great deal of weight loss.The results indicate that the asfabricated coatings have excellent water-vapor corrosion resistance.