【摘要】 采用等离子喷涂(Atmospheric plasma spraying,APS)法在炭/炭复合材料碳化硅(SiC)内涂层表面制备了硅酸钇涂层。分别采用XRD和SEM分析了所得涂层的微观结构,并测试了带有SiC/硅酸钇复合涂层的炭/炭复合材料试样在1500℃静态空气中的抗氧化性能。结果表明:通过调节喷涂粉料中的SiO2和Y2O3的摩尔比,可制得Y2SiO5、Y2Si2O7、Y2Si2O7/Y2SiO5和Y4Si3O12/Y2Si2O7/Y2SiO5四种不同结构的硅酸钇涂层;1500℃氧化73h后,SiC/Y4Si3O12/Y2Si2O7/Y2SiO5涂层试样的氧化失重速率相对较低,仅为1.01×10-4g.cm-.2h-1。更多还原

【Abstract】 Different yttrium silicate coatings for SiC-coated C/C composites were designed and prepared by an atmospheric plasma spray method to prevent the C/C composites from oxidation.XRD profiles showed that the coating was composed of Y2SiO5,Y2Si2O7,and Y4Si3O12.SEM showed that the gradient SiC/Y4Si3O12/Y2Si2O7/Y2SiO5 coating had a more compact surface than the other coatings did.Isothermal oxidation tests at 1 500 ℃ in air showed that the weight loss curves of the as-prepared C/C composites showed a linear tendency with time and the weight loss rate of all coated samples increased significantly after 73 h.The coating could protect the C/C composites from oxidation at 1 500 ℃ for 73 h in air with a weight loss rate of 1.01×10-4 g·cm-2·h-1.The SiC/Y4Si3O12/Y2Si2O7/Y2SiO5 was the better coating at high temperature than other coatings.更多还原