【摘要】 采用65%(质量分数,下同)电熔镁砂作骨料(8~5mm,5~3mm,3~1mm,≤1mm),27%电熔镁砂粉(≤0.044mm和≤0.074mm)、4%Al2O3微粉和4%SiO2微粉作基质料,以此为基础配方,首先分别用5%、10%、15%、20%的电熔白刚玉粉(≤0.044mm)等量取代同粒度的镁砂粉,然后在加入10%刚玉粉的基础上,分别用2.5%、5%、7.5%和10%的矾土基β-SiAlON(≤0.088mm)取代等量的刚玉粉,分别加水制成两组MgO基浇注料,并采用浇注料流变仪研究了刚玉粉和β-SiAlON粉的加入量对浇注料流变性(扭矩、流动阻力和粘度)的影响。研究结果表明在MgO基浇注料中加入≤10%的刚玉粉时,浇注料的扭矩、粘度和流动阻力较低,流变性较好;加入低于7.5%的β-SiAlON时,对MgO基浇注料的流变性影响不大,但超过7.5%后,浇注料的流变性趋于变差。更多还原

【Abstract】 Magnesia-based castables were prepared by using fused magnesite as aggregate(8~5 mm,5~3 mm,3~1 mm,≤1 mm),27% of fused magnesite fines(≤0.044 mm and ≤0.074mm),4% of Al2O3 ultra fine powder and 4% micro silica as matrix.Based on the formula,5%,10%,15%,20% of fused alumina (≤0.044 mm) substituted respectively the corresponding contents of same sized fused magnesite fines.While 10% of fused alumina was added,2.5%,5%,7.5%,10% of bauxite-based β-SiAlON (≤0.088 mm)substituted respectively the corresponding contents of fused alumina,and appropriate water was added.Two groups of Magnesia-based castables were finally prepared.Influences of fused alumina and β-SiAlON additions on rheological properties (torque,flow resistance and viscosity) of magnesia-based castables were analyzed by Rheometer.The results showed that when alumina addition was less or equal to 10%,the castable performed lower torque,viscosity and flow resistance but better rheological behavior;when β-SiAlON addition was below 7.5%,rheological properties were less effected.However,once the addition exceeds 7.5%,the rheological properties tended to degrade.更多还原