• Carvalho, P. A.
• Livramento, V.
• Liberal Fernandes, Hugo
• Shohoji, N.
• Nunes, Daniela
• Silva, C.
• Correia, J. B.

Abstract

<p>Nanostructured copper-diamond composites can be tailored for thermal management applications at high temperature. A novel approach based on multiscale diamond dispersions is proposed for the production of this type of materials: a Cu-nDiamond composite produced by high-energy milling is used as a nanostructured matrix for further dispersion of micrometer sized diamond. The former offers strength and microstructural thermal stability while the latter provides high thermal conductivity. A series of Cu-nDiamond mixtures have been milled to define the minimum nanodiamond fraction suitable for matrix refinement and thermal stabilization. A refined matrix with homogenously dispersed nanoparticles could be obtained with 4 at.% nanodiamond for posterior mixture with μDiamond and subsequent consolidation. In order to define optimal processing parameters, consolidation by hot extrusion has been carried out for a Cu-nDiamond composite and, in parallel, for a mixture of pure copper and μDiamond. The materials produced were characterized by X-ray diffraction, scanning and transmission electron microscopy and microhardness measurements.</p>

Topics

• nanoparticle
• impedance spectroscopy
• dispersion
• x-ray diffraction
• grinding
• milling
• strength
• composite
• transmission electron microscopy
• copper
• thermal conductivity
• hot extrusion