【摘要】 采用无压烧结技术,以0.25wt%CaO、1wt%MgO、2.75wt%SiO₂为添加剂,在1500℃、1550℃、1600℃下烧结制备了Al₂O₃陶瓷,分别在150⁴00℃温度范围内和40%¹00%的相对湿度环境下,对Al₂O₃陶瓷的直流电阻率进行检测。样品的相组成和显微结构通过X-ray衍射分析（XRD）和扫描电子显微镜（SEM）表征。结果表明,环境温度由150℃上升到400℃,样品的直流电阻率降低了约2².5个数量级;环境相对湿度从40%上升到100%,样品的直流电阻下降了约3⁴个数量级。在相同测试条件下,1500℃烧结的Al₂O₃陶瓷样品由于小的晶粒尺寸和高的孔隙率,从而导致其具有更高的电阻率。更多还原

【Abstract】 Al₂O₃ceramics were pressureless sintered at 1500 ℃,1550 ℃ and 1600 ℃ with 0. 25wt% Ca O,1wt% Mg O and 2. 75wt% Si O₂ as additives. The DC electrical resistivity of Al₂O₃ ceramics were investigated in the range of 150-400 ℃ and the relative humidity range of 40%-100% respectively. The phase composition and microstructure of Al₂O₃ samples were characterized by XRD and SEM. The results show that the temperature increases from 150 ℃ to 400 ℃,the DC resistivity of the samples decreases by about 2 to 2. 5orders of magnitude. The relative humidity increases from 40% to 100%,the DC resistivity of the samples decrease by about 3 to 4 orders of magnitude. At the same testing condition,the higher DC resistivity of Al₂O₃ samples sintered at 1500 ℃ is caused by the microstructure with smaller grain and higher porosity.更多还原