高石墨含量鳞片石墨/铜复合材料的微观结构和性能  

The microstructures and properties of graphite flake/copper composites with high volume fractions of graphite flake

作　　者：刘犇[1] 张东卿[1] 李香粉 郭晓慧[1] 师晶 刘占军[1] 郭全贵[1] LIU Ben;ZHANG Dong-qing;LI Xiang-fen;GUO Xiao-hui;SHI Jing;LIU Zhan-jun;GUO Quan-gui(Director of Key Lab of Carbon Materials,Institute of Coal Chemistry,Chinese Academy of Sciences Taoyuan south road 27,Taiyuan 030001,China;Analytical Instrumentation center,State Key Laboratory of Coal Conversion,Institute of coal chemistry,Chinese Academy of Sciences,Taoyuan south road 27,Taiyuan 030001,China)

机构地区：[1]中国科学院山西煤炭化学研究所炭材料重点实验室,山西太原030001 [2]中国科学院山西煤炭化学研究所煤转化国家重点实验室分析测试中心,山西太原030001

出　　处：《新型炭材料》2020年第1期58-65,共8页New Carbon Materials

基　　金：山西省重点研发计划(201603D121016).

摘　　要：通过真空热压烧结制备出高石墨含量的鳞片石墨/铜复合材料。研究了高石墨含量对鳞片石墨/铜复合材料微观结构和性能的影响。结果表明,随着石墨体积分数的增加(72.08 vol.%~93.34 vol.%),复合材料的密度降低(4.07~2.63 g cm^-3);电导率降低(14.71%~2.45%国际退火铜标准);面向热导率先增加后降低,在石墨体积分数为82.6%时,面向热导率达到最大值为663.73 W m^-1K^-1;面向热膨胀系数降低(6.6×10^-6~2.2×10^-6K^-1);抗弯强度降低(42.48~14.63 MPa),抗压强度降低(45.75~20.46 MPa)。鳞片石墨在复合材料中高度取向排列,分布均匀。并对预测复合材料的热导率模型进行修正,发现测量结果和模型预测结果相吻合。Graphite flake(average lateral size of 292μm and average thickness of 13μm)/copper composites with high volume fractions(72.08%-93.34%)of graphite flake were produced by a vacuum hot pressing method.Results show that the composites are anisotropic due to the alignment of the surface planes of the graphite flakes perpendicular to the pressing direction.With increasing volume fraction of graphite flakes,the density of the composites decreased from 4.07 to 2.63 g cm^-3,with the relative density apparently decreasing when the volume fraction of the flakes is more than 82.6%.In addition,the in-plane electrical conductivity decreased from 14.71%to 2.45%of the international annealed copper standard,the in-plane coefficient of thermal expansion decreased from 6.6 to 2.2×10^-6/K,the in-plane bend strength decreased from 42.48 to 14.63 MPa,and the in-plane compressive strength decreased from 45.75 to 20.46 MPa while the in-plane thermal conductivity showed a maximum of 663.73 W m^-1 K^-1 at a volume fraction of GF 82.6%.The maximum in-plane thermal conductivity is caused by inter-flake pores that are not fully infiltrated by Cu.The in-plane and out-of-plane thermal conductivity agree well with a modified layers-in-parallel model and a modified layers-in-series model,respectively.

关 键 词：高体积分数 鳞片石墨/铜复合材料 热导率 热膨胀系数 机械性能 

分 类 号：TB333[一般工业技术—材料科学与工程]