摘要
对Si-C-O-N系统进行了平衡状态下的相稳定性计算,绘制了在1473K和1573K下的Si3N4、SiC、Si2N2O和SiO2相稳定性与N2分压和O2分压的关系图以及N2分压和SiO分区的关系图,Si3N4/Si2N2O/SiC、SiO2/Si2N2O/SiC两个三固相平衡点与N2分压、O2分压和SiO分压以及温度的函数关系日。并以此确定C纤维-SiC纤维转变和C纤维上涂层SiC过程中,为获得稳定SiC相的气体分压。
The phase stability in equilibrium of the Si-C-O-N system was calculated. The phase stability diagrams for the Si3N4,SiC,Si2N2O and SiO2 at 1473K and 1573K were constructed as a function .of N2 and O2 partial pressures, and of N2 and SiO partial pressures. The diagrams which showthe changes in equilibrium N2,O2 and SiO partial pressures at invariant points (Si3 N 4 /Si2 N2 O /SiC andSiO2,/Si2N2O/SiC) as a fuction of temperatures were also given. From the phase stability calculationand phase stability diagrams, the Partial pressures of the gaseous phases can be defined, which areneeded to obtain a stable SiC phase in the processes of carbon fiber-SiC fiber conversion and coatingSiC on the carbon fibers.
基金
国家自然科学基金