Abstract: Lightweight mullite aggregates were prepared with cyanite fine powder as the main raw material,walnut shell powder as the pore forming agent,and silica sol as the binder.Effects of calcination temperatures (1 300,1 400,1 500,and 1 600 ℃ for 180 min) and holding times (1 500 ℃ for 60,120,and 180 min) on the bulk density,apparent porosity,linear change rate on heating,phase composition,and microstructure of lightweight mullite aggregates were investigated.The results show that the sample insulated at 1 500 ℃ for 60 min exhibits the optimum comprehensive properties,with bulk density of 1.18 g·cm^-3,apparent porosity of 59.8%,linear change rate on heating of 2.58%,and mullite content of 86 mass%.

Key words: silica sol, cyanite, lightweight mullite aggregate, calcination temperature, holding time

摘要： 以蓝晶石细粉为原料,核桃壳粉为造孔剂,硅溶胶为结合剂,制备了莫来石轻质骨料。研究了煅烧温度(分别为1 300、1 400、1 500、1 600 ℃,保温时间均为180 min)和保温时间(分别为60、120、180 min,煅烧温度均为1 500 ℃)对莫来石轻质骨料体积密度、显气孔率、烧后线变化率、物相组成和显微结构的影响。结果表明,在1 500 ℃保温60 min所得莫来石轻质骨料的综合性能最优,其体积密度为1.18 g·cm^-3,显气孔率为 59.8%,烧后线变化率为2.58%,莫来石相含量为86%(w)。

关键词: 硅溶胶, 蓝晶石, 莫来石轻质骨料, 煅烧温度, 保温时间