Effects of Al particles and thin layer on thermal expansion and conductivity of Al-Y_2Mo_3O_(12) cermets  

作　　者：刘献省 葛向红 梁二军 张伟风 

机构地区：[1]Henan Key Laboratory of Photovoltaic Materials and Laboratory of Low Dimensional Materials Science, School of Physics and Electronics,Henan University [2]School of Physical Science & Engineering and Key Laboratory of Materials Physics of Ministry of Education of China,Zhengzhou University [3]Zhongyuan University of Technology

出　　处：《Chinese Physics B》2017年第11期498-502,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.10974183 and 11104252);the Doctoral Fund of the Ministry of Education of China(Grant No.20114101110003);the Fund for Science&Technology Innovation Team of Zhengzhou,China(Grant No.112PCXTD337);the Industrial Science and Technology Research Projects of Kaifeng,Henan Province,China(Grant No.1501049);the Key Research Projects of Henan Higher Education Institutions,China(Grant No.18A140014)

摘　　要：Low thermal expansion composites are difficult to obtain by using Al with larger positive thermal expansion coefficient（TEC） and the materials with smaller negative TECs. In this investigation, Y2Mo3O12 with larger negative TEC is used to combine with Al to obtain a low thermal expansion composite with high conductivity. The TEC of Al is reduced by 19%for a ratio Al：Y2Mo3O12 of 0.3118. When the mass ratio of Al：Y2Mo3O12 increases to 2.0000, the conductivity of the composite increases so much that a transformation from capacitance to pure resistance appears. The results suggest that Y2Mo3O12 plays a dominant role in the composite for low content of Al（presenting isolate particles）, while the content of Al increases enough to contact each other, the composite presents mainly the property of Al. For the effect of high content Al, it is considered that Al is squeezed out of the cermets during the uniaxial pressure process to form a thin layer on the surface.Low thermal expansion composites are difficult to obtain by using Al with larger positive thermal expansion coefficient（TEC） and the materials with smaller negative TECs. In this investigation, Y2Mo3O12 with larger negative TEC is used to combine with Al to obtain a low thermal expansion composite with high conductivity. The TEC of Al is reduced by 19%for a ratio Al：Y2Mo3O12 of 0.3118. When the mass ratio of Al：Y2Mo3O12 increases to 2.0000, the conductivity of the composite increases so much that a transformation from capacitance to pure resistance appears. The results suggest that Y2Mo3O12 plays a dominant role in the composite for low content of Al（presenting isolate particles）, while the content of Al increases enough to contact each other, the composite presents mainly the property of Al. For the effect of high content Al, it is considered that Al is squeezed out of the cermets during the uniaxial pressure process to form a thin layer on the surface.

关 键 词：negative thermal expansion low thermal expansion conductivity composite 

分 类 号：TB33[一般工业技术—材料科学与工程]