TiO_2和MgO微量添加剂对Al_2O_3陶瓷烧结致密化的影响

Effect of TiO_2 and MgO Additions on Microstructures of Al_2O_3

通过在氧化铝中添加微量氧化钛和氧化镁，利用无压烧结工艺，制备了具有明显各 向异性晶粒的氧化铝块材．研究了氧化钛、氧化镁的添加量和烧结温度对材料显微结构和致密 度的影响．与单纯添加氧化钛的氧化铝材料相比，氧化镁的加入细化了氧化铝的晶粒．因此， 可以通过调整氧化镁的加入量，在保持氧化铝晶粒各向异性形貌的同时，调整晶粒的尺寸，最 终得到比较均匀的显微结构．

By using pressureless sintering technique, the samples of Al2O3 with anisotropic grains through the doping of small amount of TiO2 and MgO were prepared. The effects of quantity of TiO2 and MgO and sintering temperature on the microstructure of Al2O3 were also investigated. The doping of MgO makes the grains of Al2O3 smaller in contrast to the ones in Al2O3 doped with pure TiO2. It is possible to adjust the aspect ratio of Al2O3 grains and gain a homogeneous microstructure in Al2O3 by means of changing the amount of MgO additions in the material.