High-strength silicon nitride ceramics obtained by grain-boundary crystallization
High-strength silicon nitride ceramics obtained by grain-boundary crystallization
复制标题
晶界结晶获得高强度氮化硅陶瓷
DOI：
10.1007/bf02403951
复制
发表时间：
1991
影响因子：
4.5
通讯作者：
A. Tsuge
中科院分区：
文献类型：
--
作者：
K. Komeya;M. Komatsu;T. Kameda;Y. Goto;A. Tsuge
本文从Si_3N_4-Y_2O_3系统出发，研制了一种整体式增韧氮化硅陶瓷。然而，由于第二相的存在，断裂强度在升高的温度下降低。为了提高氮化硅陶瓷的高温强度，研究了一些添加剂。结果发现，在Si 3 N4-Y2 O3-AlN系统中添加氧化钇可以促进晶界相结晶，从而获得更高的高温强度：即热压试样在1300 °C下的3点弯曲强度为126 kg mm− 2，无压烧结试样在1300 °C下的3点弯曲强度为90 kg mm− 2。在结晶中的作用的氧化铈还不清楚，并正在通过电子显微镜和微量分析。
A monolithic type of toughened silicon nitride ceramics has been developed from Si3N4-Y2O3systems. However, because of the existence of a second phase, the fracture strength decreases at elevated temperatures. To improve the high-temperature strength of silicon nitride, some additional components were investigated. It was found that the addition of hafnia to the Si3N4-Y2O3-AIN system gave a greater high-temperature strength based on the promotion of grain-boundary phase crystallization: namely, 126 kg mm−2in 3-point bend strength at 1300 °C for the hot-pressed specimen, and 90 kg mm−2at 1300 °C for the pressureless sintered specimen. The role of the hafnia in crystallization is not yet clear, and is being characterized by electron microscopy and microanalysis.