不同微粉对刚玉质浇注料性能的影响研究

Influence of Different Micro-powders on Physical Properties of Low Cement Corundum Based Castables

在刚玉质低水泥浇注料中分别引入SiO2微粉和Al2O3/SiO2凝胶粉,研究了试样经烘烤(110℃×24h)和烧成(分别为1100℃×3h和1500℃×3h)后的气孔率、体积密度、线变化率、抗折强度及耐压强度等物理性能。研究结果表明:在刚玉质低水泥浇注料中加入Al2O3/SiO2凝胶粉和SiO2微粉均能有效地降低气孔率,提高其体积密度和强度;但微粉的引入使试样的线变化率增大,且随着热处理温度的提高,影响更加显著。微粉的引入可以有效地改善浇注料中物料的填充行为及烧结行为,从而提高浇注料的密度与强度;在浇注料中加入6wt%的SiO2微粉或6wt%的Al2O3/SiO2凝胶粉可使浇注料获得较好的综合物理性能。

Physical properties of corundum based low cement castable were studied in this paper. Fine silica powder and Al2O3/SiO2 gel was respectively added into the corundum based low cement castable samples. Physical properties of the samples treated after drying （110℃×24 h） and sintering （1100 ℃×3 h and 1500℃×3 h ） were studied, including apparent porosity, bulk density, linear change, cold modulus of rupture and cold crushing strength. Results show that the addition of Fine silica powder or Al2O3/SiO2 gel can effectively reduce the castable＇s apparent porosity, and enhance its bulk density and strength; but the addition of micro powder can enhance the linear change. The higher the treat temperature, the more remarkable the effection. The addition of micro powder can effectively improve the sample＇s filling and sintering behavior, consequently, enhance the castable＇s bulk density and strength; so, the content of micro powder should be controlled in a range. According to the experiment result, the castable can get better physical properties when the content of Fine silica powder is 6wt% or the content of Al2O3/SiO2 gel powder is 6wt%.