摘要
用化学配比n为1.0,1.3,1.5和1.8的MgO.nAl2O3粉体分别制备出了镁铝尖晶石透明陶瓷MA1.0,MA1.3,MA1.5和MA1.8。这些陶瓷是通过真空烧结和热等静压两步烧结方法制得的。由于第二相物质氧化铝晶粒的析出,陶瓷相对密度随着化学配比的增高而降低。然而,与化学配比陶瓷相比,这些非化学配比陶瓷表现出了较高的机械性能,陶瓷断面的扫描电镜照片显示非化学配比陶瓷多为穿晶断裂模式,这种断裂模式对陶瓷的强韧化作出了主要贡献。
Transparent Mg-Al spinel ceramics MA1.0, MA1.3, MA1.5 and MA1.8 was fabricated from MgO · nAl2O3 powder with n of 1.0, 1.3, 1.5 and 1.8, respectively. These ceramics were sintered to be transparent through two combined sintering processes, i.e. vacuum sintering followed by hot isostatic pressing （HIP）. Relative density of these ceramics decreases with n in MgO ~ nAI203 increasing because of second phase AI203 grains appearing in non-stoichiometric ceramics MA1.3, MA1.5 and MA1.8 during preparation. However, these non-stoichiometric ceramics show higher mechanical properties than ceramic MA1. 0. Fractural surfaces of non-stoichiometric ceramics observed by scanning electron microscopy （SEM） are featured with more transgranular fracture which contributes to improving their mechanical properties.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2008年第4期800-804,共5页
Journal of Synthetic Crystals
基金
the National Nature Science Foundation of China(No.50272040)
关键词
透明陶瓷
机械性能
非化学配比
显微结构
transparent ceramics
mechanical property
non-stoichiometry
microstructure
