钛酸钙加入量对MgO-CaO材料性能的影响

Effect of calcium titanate addition on properties of MgO-CaO materials

为了提高MgO-CaO砖在AOD炉中的使用寿命,以w（CaO）=20%的镁钙砂颗粒（粒度85、52、≤2 mm）和细粉（≤0.074 mm）为主要原料,石蜡为结合剂,添加w（CaTiO3）=93%的钛酸钙细粉（≤0.074 mm,质量分数分别为0、2%、4%、6%、8%、10%、12%和14%）,在液压机上以450 MPa压力压制成50 mm×55 mm的圆柱试样,在高温试验电炉中于1 500℃保温2 h烧成后,检测试样的显气孔率、体积密度、烧后线变化率、抗热震性能和抗渣性能。结果表明:随着钛酸钙细粉加入量的增加,试样的致密度、烧后线收缩率、常温耐压强度和抗热震性能等基本上都呈先增大后减小的变化趋势,拐点均在钛酸钙细粉加入量为8%（w）处;抗渣性能以钛酸钙加入质量分数为6%、8%的试样为最好。

In order to prolong the service life of MgO-CaO bricks for AOD furnace,the columnar specimens (φ50 mm ×55 mm)were prepared using magnesia-calcium oxide sand and fine (CaO 20 mass%,8-5, 5 -2,2-0,≤0.074 mm)as the main raw materials,paraffin as the binder,adding calcium titanate fines (CaTiO3 93 mass%,≤0.074 mm)with different additions (0,2%,4%,6%,8%,10%,12%,14%,by mass),mixing,pressing in a hydraulic press under 450 MPa,and then firing at 1 500 ℃for 2 h.The appar-ent porosity,bulk density,linear change on heating,thermal shock resistance and slag resistance were re-searched.The results show that with calcium titanate fine addition increasing,the density,linear shrinkage rate,cold crushing strength and thermal shock resistance firstly increase and then decrease,and the inflec-tion point is at 8% calcium titanate fine;the specimens perform the best slag resistance when adding 6%and 8% calcium titanate.