中间包永久衬用MgO-SiO_2-H_2O结合矾土基浇注料的研制

Preparation of MgO-SiO_2-H_2O bonded bauxite-based castables for permanent lining of tundish

以二级矾土熟料和特级焦宝石为主要原料,以电熔镁砂细粉和硅灰作结合剂,配制中间包永久衬浇注料。研究了电熔镁砂细粉和硅灰用量对MgO-SiO2-H2O结合浇注料物理性能的影响。结果表明:在硅灰和镁砂细粉的质量分数分别为4%时,该浇注料试样经110℃24 h烘干和1 100、1 400℃保温3 h热处理后的冷态耐压强度分别达99.0、138和156 MPa,1 100℃水冷热震3次后的抗折强度保持率为46%,耐压强度保持率为89%,上述性能均优于同材质低水泥结合高铝质浇注料的。

MgO-SiO2-H2O bonded bauxite-based castables for permanent lining of tundish were prepared using second class bauxite clinker and special grade flint clay as main starting materials,fused magnesia fine powder and silica fume as binders.Effects of fused magnesia powder and silica fume additions on physical properties of the castables were investigated.The results show that：when additions of fused magnesia fine powder and silica fume are both 4%（mass percent）,the cold crushing strength of the specimens dried at 110 ℃ for 24 h,1 100 ℃ for 3 h,and 1 400 ℃ for 3 h reaches 99.0,138,and 156 MPa,respectively;ratios of residual modulus of rupture and residual crushing strength of the specimen thermal shocked for three cycles（1 100 ℃,water quenching） are 46% and 89%,respectively.The above properties of the developed castables are superior to those of low cement bonded high alumina castables.