铝溶胶浸渍对RH炉用镁铬材料性能的影响

Influence of alumina sol impregnation on properties of magnesite chrome material for RH degassers

采用铝溶胶对1650℃×3h烧后的镁铬砖进行真空浸渍,然后经110℃烘干以及800℃和1550℃热处理,并对所制镁铬材料的质量变化率、耐压强度、体积密度、显气孔率和孔径分布等性能进行分析。结果表明,与未浸渍镁铬材料相比,浸渍后材料的显气孔率降低,体积密度提高;浸渍后的材料经110℃×24h烘干处理,其显气孔率最低,体积密度和耐压强最大;经800℃×3h和1550℃×3h处理后,材料的耐压强度不如未浸渍试样;经110℃×24h处理后,材料平均孔径由浸渍前的10.98μm降至7.03μm,处理效果明显;提高热处理温度对浸渍后材料的平均孔径影响不大。

Magnesite chrome brick specimens were vacuum impregnated by A-20 alumina sol after be-ing sintered at 1650 ℃ × 3 h ,and then dried at 110 ℃ for 24 h and heat-treated in the furnace at 800℃ × 3 h and 1550 ℃ × 3 h ,respectively .The mass change rate ,compression strength ,bulk density , apparent porosity and pore size distribution of the specimens were analyzed .The result shows that , compared with the raw specimen ,the impregnated specimens have lower porosity ,larger bulk densi-ty ;the specimens after impregnation at 110 ℃ have the lowest porosity and the largest bulk density and compressive strength ;the specimens after treatment at 800 ℃ × 3 h and 1550 ℃ × 3 h have smal-ler compressive strength than the raw specimen ;the average pore size of the specimens before impreg-nation is 10 .98 μm and reduced to 7 .03 μm under 110 ℃ treatment ,demonstrating obvious effect ;and raising heat treatment temperature has little effect on the average pore size .