α-Al2O3微粉加入量对刚玉干式捣打料性能的影响

摘要

In order to improve the service life of corundum lining for induction furnace,corundum dry ramming mix was prepared using brown corundum,fused magnesia,and oc-AI2o3 micropowder as main starting materials,and the influence of α-AI2O3 micropowder addition (0,1% ,2% ,and 3% in mass) on properties of corundum dry ramming mix was investigated. The results show that after heat treating at 1 600 ℃, with the increase of α-AI20, addition,the permanent change in dimensions on heating of the specimens decreases first and then increases, bulk density increases, apparent porosity decreases and the crushing strength declines first and then enhances:when the addition of α-AI2O3 is 2 mass% ,the permanent change in dimensions on heating of the specimens is relatively small and the crushing strength decreases to 22.8 MPa. The XRD and SEM results show that after firing at l 600 ℃ for 3 h small granular magnesium alumi-nate spinel forms and is well-distributed,which enhances the density.%为了提高感应炉用刚玉炉衬的服役寿命,以棕刚玉、电熔镁砂、α-Al2O3微粉为原料制备了刚玉干式捣打料,并研究了α-Al2O3微粉加入量(其质量分数为0、1％、2％和3％)对刚玉干式捣打料性能的影响.研究结果表明:经1 600℃热处理后,随着α-Al2O3微粉的增多,刚玉干式捣打料的加热永久线变化呈先减小后增大趋势,体积密度增大,显气孔率相应减小,耐压强度先减小再增大；α-Al2O3微粉加入量为2％(ω)时试样的加热永久线变化相对较小,耐压强度减小到22.8 MPa.XRD和SEM分析表明:经1 600℃3h烧后捣打料中的α-Al2O3微粉反应生成了粒状镁铝尖晶石,晶粒尺寸较小,且分布均匀,有助于捣打料致密度的提高.