Thermal management by using high thermal conductivity copper with un-bundled CNTs

Abstract

Characteristics of pure metal matrix composites reinforced with carbon nanotubes (CNTs) have been investigated. Pure Cu powders coated with un-bundled CNTs were prepared by using the surfactant (surface active agent) solution, containing both hydrophobic and hydrophilic groups, via wet process. The microstructural and mechanical properties of CNT-Cu composites were particularly investigated in detail. Cu powder with a mean particle size of 130μm and multi-wall CNTs with 20 nm in diameter were used as matrix material and reinforcements, respectively. After dipping Cu powder into the solution with CNTs, the composite Cu powders coated with CNTs were served to heat treatment in hydrogen gas atmosphere to thermally resolve the surfactant films of the powder surface. The suitable temperature for heat treatment was determined by differential thermal analysis on the composite Cu powder. The extruded Cu composite including CNTs indicated an increase of 30% in hardness and 17% in yield strength, compared to pure Cu without CNTs. The thermal conductivity of CNT-Cu composites by using wet process steadily decreased with increasing the CNT contents.