Enhanced hardness and electrical properties of copper nanocomposites reinforced by functionalized MWCNTs

摘要

Functionalized multiwall carbon nanotubes (MWCNTs)-reinforced copper (Cu) nanocomposites have been fabricated by the combination of ball milling and hot-press sintering methods. The functionalization was carried out in two levels under reflux condition. Characterization of the fabricated nanocomposites revealed that the functionalization plays an important role in enhancing the hardness and electrical properties of nanocomposites. Enhancements of up to approximate to 116% and approximate to 58% in microhardness compared to pure un-milled and milled Cu were observed by adding 1wt.% functionalized MWCNTs. On the other hand, the electrical resistivity of nanocomposites increased by increasing MWCNT contents. It was found that improved control of the Cu and MWCNT interface also leads to enhance electrical properties. Based on the experiments, the results indicated that the amount of chemically bonded oxygen atoms affects the electrical resistivity of nanocomposites. Accordingly, the nanocomposite containing 1wt.% MWCNTs with lower amount of functional groups has lower electrical resistivity.