烧结制度对钙长石质耐火材料显微结构的影响

The Influences of Sintering Systems on Microstructure of Anorthite Light Heat Insulation Refractory Materials

以镁渣,高岭土和氧化铝为原料烧结制备钙长石质隔热耐火材料,研究了烧成温度和保温时间对样品显微结构的影响。结果表明:耐火材料主要包括钙长石和氧化铝两种晶相,且随温度的升高而增加。钙长石晶粒主要为板状和等轴状,随温度升高粒径由1 μm长大到10 μm,同时聚集体逐渐增大,气孔增大并孤立。在1350℃~1370℃为较适宜烧结温度,粒径在2~5 μm,体积密度在1.52 g/cm3,显气孔率在60%。在1370℃下烧结的样品,随保温时间的延长,晶粒长大到5 μm后不再变化,聚集体逐渐小而均匀,气孔随之小而均匀,体积密度在1.50~1.53 g/cm3,显气孔率在57%~60%。

The magnesium slag, kaolin and alumina as raw material, sinter anorthite lightweight insulating refractory. The paper studied firing temperature and holding time affecting the sample microstructures. The results showed that: the new crystalline phases are mainly anorthite and alumina. With increasing temperature, grains increases which are mainly plate-like bodies and cylindrical bodies. At the same time, with the temperature grains grow up from 1 μm to 10 μm, aggregates increases, porosity increases and isolated. 1350?C - 1370?C are the appropriate sintering temperatures with grains size in the 2 - 5 μm, volume density 1.52 g/cm3 and the rate of open pores 60%. In 1370?C temperature, with holding time changing, grains size does not change after the 5 μm, but the bond formed by the aggregate grains gradually from large to small and uniformity, along with uniform pores, volume density 1.50 - 1.53 g/cm3 and the rate of open pores 57% - 60%.