摘要
通过研究SiAlON-SiC和Si3N4-SiC制品在1073K、1123K、1173K和1223K空气中氧化100h后的动态质量变化及氧化前后显气孔率、体积密度和孔径分布的改变来反映制品的抗氧化性能。结果表明,浇注成型SiAlON-SiC(简称CS)试样抗氧化性能最好,压力成型SiAlON-SiC(简称PS)试样次之,压力成型Si3N4-SiC(简称PN)试样最差。动力学分析发现,制品氧化前期符合界面反应控速模型,氧化后期符合扩散控速模型,且前后期的反应速度常数k都符合关系:kPN>kPS>kCS,k1223K>k1173K>k1123K>k1073K。
The SiAION -SiC and Si3N4 -SiC products were fired at 1073 K,1123 K,1 173 K and 1 223 K for 100 h in air. The continuous change of mass, porosity, bulk density and pore size distribution before and after oxidizing were analyzed. The results demonstrated that the oxidation resistance of cast moulding SiAION -SiC （CS） was the best,the pressure moulding SiAION -SiC （PS） next, and then the pressure moulding Si3N4 -SiC （PN）. According to kinetics theory,the products at initial oxidizing stage were controlled by chemi- cal reaction at the interface;at posterior stage controlled by oxygen diffusion through the oxide layer, The oxidation rate constant k follows the rules： kpN 〉 kps 〉 kcs, k1 223 K 〉 k1173 K 〉 k1123 K 〉 k1 073 K
出处
《耐火材料》
EI
CAS
北大核心
2007年第3期175-179,共5页
Refractories
关键词
压力成型
浇注成型
孔径分布
抗氧化性能
氧化动力学
Pressure moulding ,Cast moulding, Pore size distribution ,Oxidation resistance,Oxidation kinetics
