摘要
以刚玉细粉、碳化硅细粉、氮化硅细粉、α-Al2O3微粉和金属Al粉为主要原料，聚乙烯醇为结合剂，经球磨、混练、困料和成型后，分别在空气裸烧（氧化气氛）、埋石墨粉（还原气氛）、埋石墨＋碳化硅混合粉（还原气氛）3种气氛下进行1600℃6h热处理制备了SiAlON结合刚玉或碳化硅复合耐火材料，并研究了刚玉或碳化硅粉加入量（7．5％～90％，质量分数）和烧成气氛对SiAlON相的生成量、晶体形貌以及耐火制品的相组成、显微结构和性能的影响：结果表明：（1）随着刚玉粉含量的增加，3种气氛下烧后的SiAlON结合刚玉材料的致密度均增大，烧结性能增强；但氧化气氛下烧结性能好于还原气氛下的。（2）2种还原气氛下烧成的SiAlON结合刚玉试样的相组成均为刚玉、SiAlON和SiC；而在氧化气氛下烧成的试样出现了分层现象，其非氧化层主要为SiAlON、刚玉和少量的莫来石。（3）不同气氛下烧成的SiAlON结合刚玉材料中均有柱状或纤维状的SiAlON生成，但氧化气氛下的SiAlON柱状物比还原气氛下的要粗壮、完整得多，且成群生长。（4）随着SiC粉含量的增加，SiAlON结合碳化硅材料在2种还原气氛下烧后的致密度降低，烧结性能下降；而在氧化气氛下烧后严重氧化，形成了较厚的釉层。
Using corundum powder,SiC powder,Si3N4 fine powder,α-Al2O3 micropowder and Al powder as the starting materials, PVA as binder, after ball milling, mixing, aging ,forming and drying, SiAlON bonded corundum or SiC composites were synthesized at 1 600 ℃ for 6 h in air, graphite embedded atmosphere and （ graphite ＋SIC）embedded atmosphere,respectively. And the effects of corundum or SiC powder additions（the mass percent was 7.5%-90% ） and sintering atmosphere on forming amount and appearance of SiAlON phase, phase composition,microstructure and properties of the composites were studied. The results show that. （1）With the increase of corundum powder addition,density and sintering property of SiAlON bonded corundum composites fired in three different atmospheres all improve, but sintering property of specimens fired in oxidation atmosphere is better than that in reduction atmosphere. （2）The main phases of SiAlON bonded corundum composites fired in two reduction atmospheres are corundum, SiAlON and SiC. The specimens fired in oxidation atmosphere appear delamination phenomenon,the main phases of non-oxidation layer are SiAlQN, corundum and a little mullite. （3）Column-like or fiber-like SiAlQN forms in SiAlQN bonded corundum composites fired in three different atmospheres. Column-like SiON formed in oxidation atmosphere grows better than that in reduction atmosphere. （4）With the increase of SiC powder addition, density and sintering property of SiAlON bonded SiC composites fired in two reduction atmospheres all reduce. The specimens fired in oxidation atmosphere are oxidized and thicker glaze layer forms.
出处
《耐火材料》
CAS
北大核心
2009年第3期164-169,共6页
Refractories
关键词
SIALON
刚玉
碳化硅
相组成
显微结构
SiAION, Corundum, Silicon carbide, Phase composition, Microstructure
