Si-SiC涂层包覆石墨材料的制备及性能表征

摘要

为了防止石墨材料在高温下的氧化,以SiC和酚醛树脂为原料,采用气相渗硅法在石墨表面制备了致密的Si-SiC涂层.利用XRD、SEM对涂层的相组成与形貌进行分析,研究了涂层在1500℃以及1000℃的热循环氧化行为.结果表明:经过气相渗硅后,涂层结构致密,主要由Si和SiC组成.该涂层具有良好的抗氧化防护能力,在空气条件下1500℃和1000℃循环氧化200 h, 468 h后,包覆试样的表面质量增加分别为1.676 mg/cm2, 0.36 mg/cm2.%In order to protect graphite from oxidation at high temperature,Si-SiC coating was prepared on graphite substrate by vapor silicon infiltration using SiC and resin as raw materials. The microstructure and phase composition of the coating were studied by XRD and SEM. The oxidation tests at 1 500℃ and 1 000℃ were used to evaluate the oxidation resistance ability of the SiC-Si coating. The results show that the coating is dense,consisting of Si and SiC after the vapor silicon infiltration. The coating has good oxidation resistance ability, after oxidation at 1 500 ℃ and 1 000℃ in air,the weight gains were 1.676 mg/cm2,0.36 mg/cm2,respectively.