Microstructural Observation of Silicon Nitride Ceramics Sintered with Addition of Titania
Microstructural Observation of Silicon Nitride Ceramics Sintered with Addition of Titania
复制标题
添加二氧化钛烧结氮化硅陶瓷的显微结构观察
DOI：
10.2109/jcersj.109.1269_396
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发表时间：
2001
影响因子：
1.1
通讯作者：
T. Meguro
中科院分区：
文献类型：
--
作者：
T. Yano;Junichi Tatami;K. Komeya;T. Meguro
通过无压烧结，再加入少量的TiO2 （3mass%）进行hiping，得到Si3N4烧结体。烧结添加剂为5mass% Y2O3, 3mass% Al2O3和3mass% AlN。结果表明，晶界内分布着直径为0.2 ~ 0.5μm的圆形颗粒。颗粒中含有高密度的结晶缺陷。它们含有Ti和N，通过能量色散型x射线显微分析和x射线衍射鉴定为TiN。晶界相主要为非晶相，含Si、Y、Al和O，不含Ti。基于热力学计算和晶体化学的考虑，提出了由TiO2还原和氮化生成TiN的方法。在还原TiO2颗粒的过程中可能会引入高密度的结晶缺陷。认为圆形TiN颗粒的晶界分布有助于提高Si3N4陶瓷的耐磨性。
Si3N4 sintered body was obtained by pressureless sintering and then post-HIPing with addition of small amount of TiO2 (3mass%). Sintering additives were 5mass% Y2O3, 3mass% Al2O3 and 3mass% AlN. It was found that round-shaped particles with diameter 0.2-0.5μm were distributed within the grain-boundary phase. The particles contained high density crystalline imperfections. They contained Ti and N, and were identified as TiN by energy-dispersive-type X-ray microanalysis and X-ray diffractometry. The grain-boundary phase was mainly an amorphous phase containing Si, Y, Al and O, but it did not contain Ti. Formation of TiN from TiO2 by reduction and nitridation was suggested based on thermodynamic calculations and crystal chemical considerations. High density crystalline imperfections may be introduced during reduction of TiO2 particles. It is believed that the grain-boundary distribution of round-shaped TiN particles contributes to the improvement of wear resistance of Si3N4 ceramics.