添加浮选镁砂颗粒和Al_(2)O_(3)细粉对方镁石-尖晶石砖性能的影响

Effect of flotation magnesia particles and Al_(2)O_(3) fines on properties of periclase-spinel bricks

以烧结镁砂、浮选镁砂、电熔镁铝尖晶石和煅烧Al_(2)O_(3)细粉为主要原料,以木质素磺酸钙为结合剂,经混练、成型、1650℃烧成制备了方镁石-尖晶石砖,主要研究了以浮选镁砂颗粒替代普通烧结镁砂颗粒以及在此基础上外加不同量煅烧Al_(2)O_(3)细粉(质量分数分别为0、3%和5%)对方镁石-尖晶石砖性能的影响。结果表明:1)以浮选镁砂颗粒替代普通烧结镁砂颗粒制备的方镁石-尖晶石砖,显气孔率和常温耐压强度降低,体积密度、抗热震性、高温强度和高温韧性提高。2)在以浮选镁砂颗粒替代普通烧结镁砂颗粒制备的方镁石-尖晶石砖中,随着煅烧Al_(2)O_(3)细粉引入量的增多,显气孔率和常温耐压强度降低,体积密度、抗热震性、高温强度和高温韧性提高。

Periclase-spinel bricks were prepared using sintered magnesia,flotation magnesia,fused magnesium aluminate spinel and calcined Al_(2)O_(3) fines as starting materials and calcium lignosulfonate as the binder,mixing,shaping and firing at 1650℃.Flotation magnesia particles were used to replace ordinary sintered magnesia particles and different amounts of calcined Al_(2)O_(3) fines were extra-added(0%,3%and 5%,by mass)to investigate their effects on the properties of periclase-spinel bricks.The results show that:(1)the periclase-spinel bricks prepared with flotation magnesia particles have reduced apparent porosity and cold compressive strength,and enhanced bulk density,thermal shock resistance,hot strength and hot toughness;(2)in the periclase-spinel bricks prepared with flotation magnesia particles,as the calcined Al_(2)O_(3) fines addition increases,the apparent porosity and the cold compressive strength decrease,and the bulk density,the thermal shock resistance,the hot strength and the hot toughness are improved.