硅粉对刚玉-氮化硅复合材料表面氧化膜的影响

Effect of silicon powder on surface oxidation film of corundum-silicon nitride composites

将T-60氧化铝粉、氮化硅粉和硅粉分别按50%、37.5%和12.5%的质量分数配料混合,经压制成型后,在空气中于1600℃保温2h烧成制得刚玉-氮化硅复合材料试样,借助于XRD、SEM、EDS等研究了加入硅粉对刚玉-氮化硅复合材料表面氧化膜组成和结构的影响。结果表明:在空气中烧成的刚玉-氮化硅复合材料表面氧化膜主要由富硅玻璃相、刚玉和莫来石组成;在刚玉-氮化硅复合材料中引入硅粉能减小氧化膜厚度,并能提高氧化膜的致密程度。

Corundum-silicon nitride composites were prepared by pressing a mixture of 50 wt% T-60 alumina,37.5 wt% silicon nitride and 12.5 wt% silicon powders and firing at 1 600 ℃ for 2 h.Effect of silicon powder on composition and structure of surface oxidation film of corundum-silicon nitride composites was studied by means of XRD,SEM,and EDS.The results show that the surface oxidation film consists of silica-rich glassy phase,corundum and mullite for corundum-silicon nitride composites fired in air;the thinner and denser surface oxidation film forms by introducing silicon powder.