摘要
以氮化铝粉(w(AlN)=99%)、硅粉(w(Si)=99%)、活性氧化铝微粉(w(Al2O3)=99%)和鳞片石墨为主要原料,在流动N2气氛下分别于1 480和1 550℃制备赛隆-石墨复相材料。研究了石墨粒度(300、125、45μm)和烧成温度(1 480、1 550℃)对β-SiAlON合成率的影响,同时借助XRD、SEM等手段分析和观察了材料的物相变化和断口形貌。结果表明,在1 480和1 550℃下,石墨均阻碍了β-SiAlON的合成:在1 480℃,石墨阻碍了α-Si3N4向β-Si3N4转化,并且石墨粒度越小,阻碍作用越显著;在1 550℃,碳热还原反应加剧,石墨对15R-SiAlON的生成更有利,并且石墨粒度越小,生成15R-SiAlON的趋势越大。
The SiAION - graphite composites were prepared using AIN powder （w（AIN） =99%）, Si powder （ w（ Si ） = 99% ）,reactive α-AI2O3 powder（w（AI2O3） =99% ） and flake graphite as main starting materials in flowing N2 atmosphere at 1480 and 1550℃. The influences of particle size （300,125 and 45μm） of flake graphite and firing temperature （1480 and 1550℃） on β-SiAION synthesis rate were studied. The phase compositions and fracture structure of the composites were determined and observed by XRD and SEM. The results showed that either at 1 480℃ or at 1550℃,the flake graphite restrained the synthesizing of β-SiAION. At 1480℃,the forming of β-Si3N4 from α-Si3N4 was restrained by graphite,the smaller the graphite particle size was, the more obvious the restrain was. At 1550℃,carbothermal reduction was strong ,graphite was beneficial to the forming of 15R-SiAION,and the smaller the graphite particle size was,the more the 15R-SiAION was formed.
出处
《耐火材料》
CAS
北大核心
2008年第6期405-408,共4页
Refractories
