摘要
研究了孔隙率为9.4％的SiC/55MoSi_2(其中SiC体积分数为45％,MoSi_2体积分数为55％)电热材料的微观结构和电热性能。材料中的SiC被MoSi_2包围,两种组分的连接处虽然边界清晰,但并不存在成分的突变,有一宽度小于4μm的成分过渡区。过渡区内Fe,W杂质元素富集于靠近MoSi_2的一侧。氧元素的最高含量没有处于过渡区的中间部位,而是富集于靠近MoSi_2的一侧。温度与氧化质量增量关系表明,1560℃以下材料的氧化质量增量变化很小,接近单一的MoSi_2材料。材料中SiC组分氧化所产生的CO或CO_2气体,形成细小而分散的气泡,并停留在表面氧化层中。
Microstructure and electrical-heating properties of SiC/55MoSi2 (SiC 45%, MoSi2 55%, in volume) electrical-heating materials with the porosity of 9.4% were studied. Results indicate that SiC particles are surrounded by MoSi2 in the materials. Although the boundary of the two kinds of particles is clear, there is not a sudden change of compositions. There is a transition zone of composition with the width of less than 4 μm. Fe and W elements in the transition zone are rich on the side of MoSi2. The highest content of oxygen is not in the middle of the transition zone, but on the side of MoSi2. The relationship of temperature and mass change shows that the change of the mass gain of oxidation is slight below 1560°C and it approaches to the single MoSi2. CO or CO2 produced by the oxidizing of SiC composition forms fine and disperse bubbles. Those bubbles remain in the surface oxidation layer.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2003年第9期862-866,共5页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(No.50171037)
关键词
电热材料
氧化
二硅化钼
碳化硅
过渡区
Microstructure
Molybdenum compounds
Oxidation
Physical properties
