La2O3对热压烧结Al2O3性能的影响

La₂O₃对热压烧结Al₂O₃性能的影响

摘要: 以高纯的α-Al₂O₃为原料, 以MgO、La₂O₃为烧结助剂, 采用热压烧结工艺制备Al₂O₃。用阿基米德法、SEM、XRD等研究了材料的烧结性能、显微结构和相组成; 用三点弯曲法测试材料的力学性能, 用阻抗仪和氦质谱检漏仪分别测试试样的介电性能和气密性。结果表明: 在1500 ℃烧结制备的材料晶粒细小, 平均晶粒尺寸小于1 μm, 样品的抗弯强度达到600 MPa以上; La₂O₃加入量为2%时, 介电损耗为4.00×10^-4, 漏气率为2.2×10^-9 Pa·m³·s^-1。

Abstract: Al₂O₃ materials with MgO and La₂O₃ as additives were prepared by hot-pressing. The density, microstructure and phase composition of the samples were studied by the Archimedes method, SEM and XRD. The mechanical properties were studied by the three-point bending test. The dielectric properties and gas tightness were studied by the resistance meter and helium mass spectrometer leak detector. The results show that the average grain size of the sample sintered at 1500 ℃ is less than 1 μm. The bending strength of samples is more than 600 MPa. The dielectric loss is 4.00 × 10^-4 and the leak rate is 2.2×10^-9 Pa·m³·s^-1 for the sample with 2% La₂O₃.