摘要
将由50% (质量分数,下同)氧化铝粉、37. 5%氮化硅粉和12. 5%硅粉组成的混合料和由62. 5%氧化铝粉和37. 5%氮化硅粉组成的混合料分别压制成试样,分别在空气和埋炭气氛中于1600℃保温2h烧成,然后检测试样的体积密度、显气孔率和常温耐压强度,并采用XRD、SEM、EDS等手段分析试样的物相组成和显微结构。结果表明:与未加硅粉的试样相比,加入硅粉的试样在两种气氛中烧成后,显气孔率较低,强度较大,说明硅对刚玉-氮化硅材料具有助烧结作用;在空气中烧成后,试样中残留有较多的单质硅,这些单质硅均匀分布于刚玉和氮化硅颗粒的空隙间;在埋炭气氛中烧成后,单质硅原位反应生成了O’SiAlON和SiC。
Specimens with mixed powders of 50 wf%Al2O3, 37.5 wf%Si3N4 and 12.5 wt%S1 as starting materials were sintered at 1600°C and soaking 2 hours in air atmosphere and embedded carbon atmosphere respectively. Bulk density, apparent porosity and cold crushing strength at room temperature were determined, and phase composition and microstructure of the specimens were investigated by means of XRD, SEM and EDS. The results show that specimens containing silicon have lower apparent porosity, higher strength and lower bulk density than those no addition of silicon. The results indicate that silicon has remained and distributed evenly in the interstices of particles after sintering in air atmosphere, while the silicon converts into O'-SiAION and silicon carbide by in-situ reaction in embedded carbon atmosphere.
出处
《耐火材料》
EI
CAS
北大核心
2005年第2期85-88,共4页
Refractories
基金
国家自然科学基金资助项目(50172007 )
国家自然科学基金重点基金资助项目(50332010)。
