SrO对镁铝尖晶石烧结性能的影响

Influence of SrO on sintering properties of magnesia-alumina spinel

以Al_(2)O_(3)、Mg(OH)_(2)和SrO为原料,引入质量分数分别为0、0.25%、0.5%、0.75%、1%的SrO制备镁铝尖晶石。采用X射线衍射仪、扫描电子显微镜、显气孔率、体积密度测定仪和图像处理软件,对烧结后的试样进行分析。结果表明:不同烧结温度煅烧后,随SrO含量逐渐增加,试样烧结后线收缩率和体积密度先增大后减小,显气孔率先减小后增大,当SrO添加量为0.5%时,线变化率和体积密度最大,显气孔率最小。试样在1600℃下保温3 h时,未添加SrO制备的镁铝尖晶石烧结后线变化率为4.9%,显气孔率为50.1%,体积密度为1.64 g/cm^(3);而添加了0.5%SrO制备的镁铝尖晶石线变化率为5.4%,显气孔率为44.3%,体积密度为1.89 g/cm^(3)。

Magnesia alumina spinel was prepared from Al_(2)O_(3),Mg(OH)_(2)and SrO,with mass fractions of SrO is 0,0.25%,0.5%,0.75%and 1%,respectively.The sintered samples were analyzed by X-ray diffractometer,scanning electron microscope,apparent porosity and bulk density tester and image processing software.The results show that after calcination at different sintering temperatures,with the increase of SrO content,the linear shrinkage and bulk density of the samples increase first and then decrease,and the apparent porosity decreases first and then increases.When the addition of SrO is 0.5%,the linear change rate and bulk density are the largest and the apparent porosity is the smallest.When the sample is sintered at 1600℃for 3 h,the linear change rate of magnesium aluminum spinel prepared without SrO after sintering is 4.9%,the apparent porosity is 50.1%,and the bulk density is 1.64 g/cm^(3);The linear change rate of magnesia alumina spinel prepared by adding 0.5% SrO is5.4%,the apparent porosity is 44.3%,and the bulk density is 1.89 g/cm^(3).