Electrical resistivity of silicon nitride–silicon carbide based ternary composites
Electrical resistivity of silicon nitride–silicon carbide based ternary composites
复制标题
DOI：
10.1016/j.jeurceramsoc.2011.08.002
复制
发表时间：
2012
影响因子：
5.7
通讯作者：
E. Zschippang;H. Klemm;M. Herrmann;K. Sempf;U. Guth;A. Michaelis
中科院分区：
文献类型：
--
作者：
E. Zschippang;H. Klemm;M. Herrmann;K. Sempf;U. Guth;A. Michaelis
通过添加体积分数为8%的导电添加剂，的ZrN或ZrB 2到Si 3 N 4-SiC基体上。在热压过程中，ZrB 2与Si 3 N4反应生成ZrSi 2、ZrN、Si和BN，而ZrN在Si 3 N4-SiC-ZrN复合材料中不发生任何反应。与基体（3×104Ωcm）相比，ZrN或ZrB 2改性的复合材料的电阻率（7×103Ωcm和3×10−1Ωcm）较低。进一步研究了ZrN和ZrSi 2颗粒的粒度分布和导电相与非导电相的体积比，排除了ZrN和ZrSi 2颗粒的渗流网络。事实上，掺杂的SiC晶粒和改性的晶界作为烧结过程中形成液相的结果被认为是含ZrSi 2的材料的电阻率显著较低的原因。所有热压复合材料的复合电阻率的降低，由于随后的热处理获得。
New electrically conductive ternary composites were developed by adding 8vol.% of ZrN or ZrB2to a Si3N4–SiC matrix. During hot pressing, ZrB2reacted with Si3N4to form ZrSi2, ZrN, Si and BN whereas added ZrN did not undergo any reactions in the Si3N4–SiC–ZrN composite. The composites modified by ZrN or ZrB2addition showed a lower resistivity (7×103Ωcm and 3×10−1Ωcm) compared to the matrix (3×104Ωcm). Further studies on the grain size distribution and the volume ratio of conducting and non-conducting phases excluded a percolation network of ZrN and ZrSi2grains. In fact, doping of SiC grains and modified grain boundaries as a consequence of the formation of liquid phases during sintering are suggested to be the reason for the significantly lower resistivity of materials containing ZrSi2. A decrease in the composite resistivity due to a subsequent heat treatment was obtained for all hot-pressed composites.