以MnO_2-TiO_2-MgO为添加剂注浆成型低温烧结Al_2O_3陶瓷

Low Temperature Sintering of Alumina Ceramics with MnO_2-TiO_2-MgO Additives

采用注浆成型方法,通过加入MnO2-TiO2-MgO复相添加剂,在1350℃空气气氛中常压烧结,获得了相对密度最大为95.7%的氧化铝陶瓷。研究了MnO2-TiO2-MgO复相添加剂对氧化铝陶瓷显微结构与力学性能的影响。在添加质量分数为3%MnO2,0.5%MgO的情况下,比较添加不同质量分数的TiO2（1.0～3.0%）对氧化铝陶瓷烧结性能的影响。通过对比发现,该复相添加剂能有效降低氧化铝陶瓷的烧结温度,在同一温度下,随着TiO2的增加,烧结体密度也随之增加,强度也有明显差别。结果表明,1350℃下Al2O3＋0.5%MgO＋3%MnO2＋1.5%TiO2体系烧结效果最好,断口为沿晶断裂,无明显气孔,晶粒分布均匀,平均粒径为2μm,无晶粒异常长大现象。烧结体密度达到3.80g/cm^3,抗弯强度为243MPa。

In this paper, alumina ceramics with a relative density of 95.7% were successfully fabricated at a low sintering temperature of 1350℃ assisted by MnO2-TiO2-MgO muhiphase sintering additives using simple slurry casting method. The effects of MnO2-TiO2-MgO muhiphase sintering additive on the sintering property and microstructure of the ceramics were studied. The results showed that the muhiphase sintering additive can effectively decrease the sintering temperature of the ceramics. Especially, the optimum sintering result was achieved with 0.5% MgO, 3% MnO2 and 1.5% TiO2 additives, the sintered alumina ceramics had a uniformly distributed grain size of 2μm in average, no detectable abnormal grain growth and a density of 3.98g/cm^3. The flexture strength was 243MPa.