摘要
对SiC纤维的直流电阻加热CVD工艺进行了研究,实验采用将两种硅烷的比例混合液体通过液体流量计计量供液并即时完全汽化后与氢气混合输入到反应管并在水冷水银封入气口通入顶吹氢的供气方案,从而简化了工艺并解决了反应气体冷凝问题.在CVD工艺研究中发现影响纤维沉积质量的因素主要有沉积温度、反应气体组分及流量、走丝速度等工艺参数,此外还发现直流电阻加热CVD工艺中,反应管前后存在约200℃的温差,采用双沉积室工艺可减缓温差.在一定的沉积参数下,可沉积出直径60～100μm、抗拉强度3100～4080MPa的SiC纤维.
The CVD process of SiC fibre prepared by DC electrically heating was investigated. In the test, small flux of mixture liquid of CH3SiCl3 and CH3SiHCl2 was fed into heating furnace and gasified immediately. Then the silane vapour mixed with H2 was introduced to reactor tube after heating again. Furthermore, a small amount of H2 was led at the gas entrance sealed by mercury. It was found that the problem of silane vapour condensation in gas flowmeter and water-cooling mercury seal can be avoid by using fluid flowmeter in place of gas flowmeter. The effects of some parameters in CVD process such as deposition temperature, the gas flux and flow ratio, tungsten filament feeding speed on filament deposition quality were examined. The temperature distribution alone the length of substrate was also studied. The results showed that the temperature variations in single deposition reactor was about 200℃ and the temperature variations can be reduced by using two deposition reactors. In certain CVD parameters, the average strength of CVD-SiC fibre is 3100 4080MPa with 60-100μm in diameter.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2005年第10期47-51,共5页
Journal of Materials Engineering
