莫来石溶胶结合高铝质耐火材料性能的研究

Properties of Mullite Sol Bonded with High Aluminum Refractories

为了提高高铝质耐火材料的综合性能,利用共沉淀法得到的莫来石溶胶为结合剂制备高铝质耐火材料。利用XRD和SEM等手段对莫来石溶胶的组成、显微结构和性能进行分析和表征,通过检测高铝质耐火材料试样的体积密度、显气孔率、线变化率和常温耐压强度,重点研究莫来石溶胶的性能及对高铝质耐火材料烧结性能和抗热震性能的影响。结果表明:经1100℃烧后莫来石溶胶的比表面积为26.02 m2/g,溶胶经1300℃烧后完全转化成莫来石;莫来石溶胶的加入使得高铝质耐火材料试样的体积密度增大,显气孔率降低;莫来石溶胶与Al2O3晶形转变的协同作用提高了莫来石溶胶结合高铝质耐火材料的常温耐压强度和热震稳定性。

In order to improve the comprehensive properties of high alumina refractory,the preparation of high alumina refractories by using the mullite sol as a binder obtained by coprecipitation method. The phase composition,microstructure and property of mullite sol were characterized by X-ray diffraction and scanning electron microscopy. By examining the bulk density,apparent porosity,linear shrinkage rate and cold compression strength of high alumina refractories,the properties of mullite sol and the effect of mullite sol on the sintering property and thermal shock resistance of high-alumina refractories were mainly investigated. The results show that the specific surface area of mullite sol is 26. 02 m2/g after firing at 1100 ℃,and the sol powders are completely converted into mullite after firing at 1300 ℃. The bulk density of high alumina refractories increases with the addition of mullite sol,and the apparent porosity decreased. The cold compression strength and thermal shock resistance of mullite sol bonded with high aluminum refractories is improved by the synergistic effect of mullite sol and Al2O3 crystal transformation.