碳纳米管-银复合材料的制备工艺和电导率

Processing and electrical conductivity of carbon nanotubes-silver composites

采用粉末冶金方法制备碳纳米管银复合材料,研究了制备工艺、碳纳米管含量对碳纳米管银基复合材料密度、硬度、抗弯强度、电导率的影响。结果表明:采用复压烧结,烧结温度为700℃时,复合材料的性能较好;碳纳米管和银的弱界面结合,使得碳纳米管对复合材料的强化效果不明显;当碳纳米管的体积含量大于10%时,碳纳米管在晶界上发生偏聚,碳纳米管银界面对电子产生散射,导致复合材料的电阻率迅速增加。

Carbon nanotubes-silver composites were prepared by powder metallurgical method. The influence of processing parameters and the content of carbon nanotubes on the relative density, hardness, bending strength and electrical conductivity of carbon nanotubes-silver composites were investigated. The results show that the composite has comprehensive properties by using re-pressing process and sintering at 700 ℃. Bending strength of the composites materials is not obviously reinforced by carbon nanotubs, because of poor interfacial bonding between the multiwall carbon nanotubes and silver. Because of the clustering of carbon nanotubes, the electrical resistance of composites increases with the increase of the content of carbon nanotubes when the content of carbon nanotubes is higher than 10%(volume fraction).