摘要
以Mo粉和Si粉为原始粉末,采用熔浆法在C/C复合材料表面原位合成了Si3N4-MoSi2/Si-SiC(MSN)系多层抗氧化涂层,借助扫描电镜和X射线衍射仪等分析手段对涂层的相组成和微观组织进行表征,并对涂层的抗氧化性能进行了初步研究.结果表明:Si浆料中添加适量Al可有效地阻止液态Si渗入C/C基材内部,3%Al-Si涂层具有最好的阻止Si渗入作用;Al含量超过3%时,Si的渗入程度随Al含量的增加而加剧;涂层中MoSi2的理论含量超过50%时,MSN-C/C复合材料1 400℃的抗氧化性能随MoSi2含量的增加而显著下降;MSN30-C/C和MSN40-C/C复合材料均在1 200～1 400℃表现出相近的抗氧化能力,但只有MSN30-C/C复合材料表现出抗1 450℃氧化的能力.
In-situ Si3N4 - MoSi2/Si - SiC （ MSN ） multi-layered anti-oxidizing coatings for Carbon/Carbon （ C/ C） composites were fabricated in nitrogen atmospheres by means of fused slurry process using Mo and Si powders. The microstructure and phase compositions were characterized by scanning electron microscopes and Xray diffractometer. The results indicate that the proper Al additive suppresses the excessive infiltration of liquid Si into C/C substrate while does not affect the formation of SiC bonding layer. The minimum infiltration amount of Si into C/C substrate was obtained using the 3wt% Al - Si slurry. When the Al content in Al - Si slurry is above 3wt% , the more Al additive the more Si infiltration. When MoSi2 content exceed 50vol% in sintered coating, the oxidation resistance of MSN - C/C composites obviously decreases with increasing of Mo-Si2 content. MSN30 - C/C and MSN40 - C/C composites exhibit similar oxidation resistance in the range of temperature from 1 200 ℃ to 1 400 ℃. But only MSN30 - C/C composites present anti-oxidizing ability at 1 450 ℃.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2005年第5期462-465,共4页
Materials Science and Technology
基金
哈尔滨工业大学校青年基金资助项目(HIT.2001.18)
黑龙江省留学回国基金资助项目(LC04C16)
