Strengthening of Aluminum with Functionalized Multiwalled Carbon Nanotubes by Mechanical Alloying and Sintering

Undergraduate #366
Discipline: Technology and Engineering
Subcategory: Materials Science

Alfer Castro - University of Puerto Rico, Mayagüez Campus
Co-Author(s): Héctor Colón, Johnny López, Catalina Ramírez, Catherine Castro, David Florián, Sujeily Soto, and O. Marcelo Suárez, University of Puerto Rico, Mayagüez Campus

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Aluminum is an attractive metal due a combination of cost and mechanical properties. In particular, aluminum matrix composites target a wide range of applications such as strut assemblies, electrical components, and structural parts. This research focuses in the strengthening of a pure aluminum matrix by adding functionalized multiwalled carbon nanotubes (MWCNs). The synthesis of the composite starts with a –COOH ligand as a functionalizing agent of the nanotubes, dispersed in isopropanol as solvent. This is followed by cold-welding to the aluminum matrix via high-energy ball milling. The resulting powder is then compressed into pellets and sintered at 500ºC. Thermal and mechanical properties of these composite were then compared to pure aluminum. The experimental results revealed improvements in hardness and wear resistance provided by the COOH functionalization and covalent bonding linking the functionalized MWCNs. This is a simple and cost effective fabrication methodology to prepare an aluminum matrix for applications where high thermal conductivity and high mechanical strength are mandatory.

Funder Acknowledgement(s): This material is based upon work supported by the National Science Foundation through Grant No. 1345156 (CREST program).

Faculty Advisor: O. Marcelo Suárez, msuarez@ece.uprm.edu