摘要
用恒温热重法测定了热压SiC-Al_2O_3复相陶瓷在1500℃空气中的氧化增重速率,并研究其高温氧化行为.氧化动力学测定结果表明,热压SiC-Al_2O_3复相陶瓷材料的氧化增重速率随氧化时问延长而减小;反应气体氧和反应产物气体CO通过氧化产物边界层的扩散过程与氧化反应过程相比是很慢的,成为氧化速率限制过程.
Hot-pressed SiC-Al_2O_3 multiphase ceramics were oxidized in air at 1500℃ in a thermobalance and the oxidation behavior of hot-pressed SiC-Al_2O_3 multphase ceramics at high temperature was studied. The results of oxidation kinetics experiments indicated that the average mass increase rates of the hot-pressed SiC-Al_2O_3 multiphase ceramics decreased with exposure time. It was shown that the oxidation rate limiting process was the diffusion of the gaseous species (O_2 and CO) through SiO_2 and 3Al_2O_3·2SiO_2 boundary layer.
出处
《湖南大学学报（自然科学版）》
EI
CAS
CSCD
1993年第6期55-58,共4页
Journal of Hunan University:Natural Sciences
关键词
复相陶瓷
高温氧化
碳化硅
氧化物
hot-pressed SiC-Al_2O_3
oxidation behavior
limiting process
