Novel Fabrication Route to High Strength Metal-Carbon Nanotube Composites
Z. Iqbal, F. Owens, D. Wiegand
New Jersey Institute of Technology, US
Keywords: carbon nanotubes,nanotube infiltration, mechanical strength
Abstract:There have been until recently no reports of significant enhancements of yield strength in metal-carbon nanotube composites, although there have been a number of attempts to fabricate these novel materials. A major challenge has been to develop methods that incorporate single wall and multiwall carbon nanotubes (SWNTs and MWNTs) into metals without damaging the nanotubes during processing. We have recently developed a direct and controllable method of incorporating carbon nanotubes into iron to provide a 45% enhancement of the yield strength of the composite containing 2.2% by volume of nanotubes relative to a similarly fabricated part of pure iron. This technique has now been extended to infiltrate an aluminum alloy part with carbon nanotubes to give aluminum parts with enhanced hardness and potentially, increased strength. Further development of the fabrication technique will involve the initial, room temperature infiltration of catalyst-decorated carbon nanotubes into a porous metal structure to give an aligned carbon nanotube-metal network that will be infiltrated further with nanotubes and consolidated at higher temperatures to give the final composite. Electron microscopic and mechanical property investigations coupled with modeling of the interfacial structures are planned, and some parts of the work have been initiated.