• 作者： Chen, Chih-Cheng; Yen, Fu-Su
• 中文摘要： 近年來,SiC鬚晶強化複合材料的研究雖然很多,但有關此複合材料之粉末特性的研究卻相當稀少。本研究即採用溶膠-凝膠法研製SiC鬚晶強化氧化鋁-氧化矽複合材料粉末,此粉末是以非晶質SiO/sub 2/被覆於SiC鬚晶或氧化鋁粉末外層的方式來製備,並從不同的製備條件去探討粉末特性。結果發現,在pH=12.6的水解條件下,非晶質SiO/sub 2/可均勻被覆於鬚晶與氧化鋁粉粒的外層,且具有最大之氧化物含量與較短的凝膠時間。此複合材料粉末的分散行為則受 SiO/sub 2/被覆層的表面性質影響,在pH=4或10.5的條件下,可獲得分散良好的泥漿。這些泥漿以壓濾成形法可獲高密度之生坯,其燒結密度可達92%的理論密度以上。
• 英文摘要： SiC-whisker reinforced composites, although having been extensively studied, have received little attention in regards to the characteristics of their composite powders. Preparation of SiCw-Al/sub 2/O /sub 3/-SiO/sub 2/ composite powders was investigated in this study. Commercially purchased SiC whiskers and Al/sub 2/O/sub 3/ powders were coated with amorphous silica by sol-gel methods. SiC whiskers or the alumina particles were found to be capable of being homogeneously coated by amorphous silica via hydrolysis of TEOS at pH=12.6, at which the silica gel precipitated exhibited the highest oxide content with shorter gelation time. Dispersion of the composite powders was affected by the silica coatings. Well-dispersed slurrys were obtained at aqueous pH=4 or 10.5. Pressure filtration proved that the green compacts processed were of high bulk density and could be sintered to >92% T.D.
• 中文關鍵字： 碳化矽; 複合材料; 粉末; 溶膠; 凝膠; 凝膠時間; 分散; 加壓過濾; 氧化鋁; 氧化矽
• 英文關鍵字： Silicon Carbide; Composite Material; Powder; Sol; Gel; Gelation Time; Dispersion; Pressure Filtration; Alumina; Silica