通过掺杂不同浓度Tb2O3的重稀土氧化物,研究不同烧结温度下二元MgO-Tb2O3对氧化铝陶瓷电弧管组织与性能的影响,并与MgO-CaO掺杂体系进行比较。结果表明:在相同工艺条件下,CaO掺杂样品晶粒组织粗大且分布不均匀;添加重稀土氧化物Tb2O3可降低氧化铝陶瓷电弧管的晶体颗粒尺寸;在较低烧结温度下,掺杂Tb2O3能够细化晶粒、提高微观组织均匀性、消除晶粒异常生长及有效地改善透明氧化铝陶瓷电弧管的力学性能。
The effect of Tb2O3 doping with different concentrations on the microstructures and mechanical properties of alumina arc tube was investigated under different sintering temperatures, and the influence of CaO doping alumina are tube was also investigated for comparison. The results show that, contrasting to the coarse grain size and uniform microstructures of the alumina arc tube doped with CaO, heavy rare-earth Tb2O3 doping can decrease the grain size and enhance densification effectively. At relative lower sintering temperature, Tb2O3 doping can further eliminate the abnormal grain growth and improve the microstructure homogeneity and mechanical properties of transparent alumina arc tube.