摘要
以不同粒度的SiC、硅粉为原料,采用浇注成型制备反应烧结氮化硅结合碳化硅。选用不同浓度的硅溶胶、铝溶胶和氯化铝溶液,分别对坯体和1420℃氮气气氛下烧成后的试样进行真空浸渍。研究了烧前浸渍和烧后浸渍、浸渍液的种类和浓度等对试样氮化率、体积密度和显气孔率的影响。结果表明:对材料进行烧前浸渍和烧后浸渍均可以增加试样的致密度,但烧后浸渍的效果不如烧前浸渍;高浓度浸渍液不利于致密度的提高;在三种浸渍溶液中,烧前浸渍铝溶胶的试样氮化率提高最为明显,而浸渍氯化铝溶液的试样气孔率下降最为明显;综合考虑浸渍对致密度和氮化率的影响,采用烧前浸渍10%铝溶胶的试样效果较好。
Reaction sintered silicon nitride bonded silicon carbide was prepared by slip casting using different size of SiC and silicon powder as raw materials. The green bodies and the samples sintered at 1420 ℃ under nitrogen atmosphere were impregnated by different concentration of silica sol, aluminum sol and aluminum chloride solution in vacuum, respectively. The effects of the impregnation before and after sintering, the kind of impregnation solutions, and the concentration of impregnation solutions on the nitriding rate, bulk density and apparent porosity of the samples were investigated. The results show that the densification of the samples can be increased by the impregnation before and after sintering, but the impregnation after sintering is not as good as that before sintering. High concentration of impregnation solution is unfavorable for the densification. For the impregnation before sintering by three kinds of impregnation solutions, the nitriding rate of the sample impregnated by aluminum sol increases most apparently, whereas the porosity of the sample impregnated by obviously. Considering comprehensively the densification and aluminum chloride solution decreases most nitriding rate, the sample impregnated by 10% concentration of aluminum sol shows the best results.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2013年第4期714-718,共5页
Bulletin of the Chinese Ceramic Society
基金
陕西省工业攻关项目(2011K07-16)
关键词
氮化硅结合碳化硅
浸渍
致密度
氮化率
silicon nitride bonded silicon carbide
impregnation
densification
nitriding rate
