矾土基Al_2O_3-MgO质振动浇注料的流变性能

Rheological property of bauxite based Al_2O_3-MgO vibration castable

采用新型浇注料全组分流变仪,针对矾土基Al2O3-MgO质振动浇注料,测定了不同种类硅灰及其加入量、镁砂粉加入量、三聚磷酸钠加入量和不同粒度分布系数对流变性能的影响.研究结果表明:在振动条件下,全组分铝镁质振动浇注料具有Bingham流体的特征,并具有剪切稀化和正触变性.硅灰种类对浇注料的流变性有一定的影响.硅灰含量(质量分数3%～5%)对浇注料的流变性有较大影响,随着硅灰加入量的增大,浇注料的流变性逐渐变好.在实验的镁砂粉粒度下,镁砂粉含量(质量分数4%～12%)对浇注料的流变性影响较小.三聚磷酸钠加入量(质量分数0.13%～0.19%)对浇注料的流变性影响较大,随分散剂加入量的增加浇注料的流变性逐渐变好,在0.19%时又变差,最佳加入量为0.15%～0.17%.随粒度分布系数增大(0.23～0.31),浇注料所需的加水量逐渐降低,流变性逐渐变好,0.29以后变化不大.浇注料的流变性和流动性有较好的相关性.浇注料的流变性越好,流动性也越好.

The effect of the kind and content of silica fume, the contents of magnesia fine and sodium tripolyphosphate （STP）, and particle size distribution coefficient （Andreasen coefficient） on the theological property of bauxite-based Al2O3-MgO castable were researched with a new developed castable rheometer. The results show that under vibration conditions, the castable has characteristics of the Bingham model, with shear-thinning and thixotropic property. The type of silica fume has some effect on the rheology of the castable. The content of silica fume in the range of 3 % to 5 % has significant effect on the theology of the castable; with the increase of silica fume＇s addition, the rheology of the castable gets better. At the particle size of magnesia fine in this experiment, the content of magnesia fine in the range of 4 % to 12 % has little effect on the rheology of the castable. The addition of STP in the range of 0.13 % to 0.19 % has obvious effect on the rheology of the castable. With the increase of STP＇s addition, the rheology of the castable get better, but the effect gets worse at the addition of 0.19%. The best addition of STP is 0.15% to 0.17%. With the increase of particle size distribution coefficient in the range of 0.23 to 0.31, the water demand for the same flow value is decreased, and the rheology get better too, but no more effect when higher than 0.29. There is good relevance between the rheology and flow ability. The better the rheology, the better the flow ability is.