添加氧化铈对反应烧结制备镁铝尖晶石材料性能的影响

Effects of cerium oxide addition on properties of magnesia-alumina spinel materials prepared by reaction sintering

为了进一步提高高品质钢冶炼用镁铝尖晶石耐火材料的关键性能,以电熔镁铝尖晶石、轻烧氧化镁和白刚玉为原料,镁铝溶胶为结合剂,氧化铈为添加剂,采用反应烧结工艺成功制备了镁铝尖晶石材料。系统研究了氧化铈添加量(质量分数,0、3%、6%、9%和12%)对合成镁铝尖晶石材料显气孔率、体积密度、线收缩率、体积收缩率、常温耐压强度和抗热震性等性能的影响。研究结果表明,添加氧化铈可以明显改善镁铝尖晶石材料的烧结性能;随着CeO_(2)加入量的增加,其显气孔率先降低后略微增加,体积密度先增加后减小,线收缩率和体积收缩率逐渐增加;添加质量分数为6%的CeO_(2)试样的综合性能较优,其显气孔率为13.94%,体积密度为3.45 g/cm^(3),线收缩率为2.86%,常温耐压强度为162.74 MPa,一次热震循环后强度保持率为91.25%。

To further improve the key performance of magnesium-aluminum spinel refractories for the production of high-quality steel,magnesia-alumina spinel materials were successfully prepared by reaction sintering process using fused magnesia-alumina spinel,light-burned magnesia and white corundum as raw materials,magnesia-alumina sol as binder and cerium oxide as additive.Effects of cerium oxide addition amounts(0,3 wt.%,6 wt.%,9 wt.%and 12 wt.%)on the apparent porosity,bulk density,linear shrinkage ratio,volume shrinkage ratio,cold compressive strength and thermal shock resistance of as-prepared magnesia-alumina spinel materials were studied in detail.The results show that the sintering properties of magnesia-alumina spinel materials are obviously improved by adding cerium oxide.With the increase of CeO_(2) addition amounts,the apparent porosity of the samples is firstly decreased and then slightly increased,the bulk density firstly is increased and then decreased,the linear shrinkage ratio and volume shrinkage ratio are increased.Many better comprehensive properties of the sample added with 6 wt.%CeO_(2) are obtained,and the apparent porosity is 13.94%,the bulk density is 3.45 g/cm^(3),the linear shrinkage ratio is 2.86%,the cold compressive strength is 162.74 MPa,and the residual strength rate after one-time thermal shock cycle is 91.25%.