DUREZA Y PROPIEDADES ESTRUCTURALES DE COMPUESTOS BASADOS EN NANOTUBOS DE CARBONO Y ALUMINIO

Powder Metallurgy was used for the preparation of aluminum composite reinforced with multiwall carbon nanotubes (MWCNTs). The MWCNTs were synthesized by Chemical Vapor Deposition (CVD), using C 2 H 2 as precursor gas, Ar as a carrier gas, and Fe-Co / CaCO 3 as a catalyst. The powder aluminum was mixed with MWCNTs in a planetary ball milling device for different weight ratios, from 0% to 2%, and different times stages in the mixing process (3 min and 60 min). The powders compounds were doubled hot-pressed and sintering and analyzed using a Field Emission Scanning Electron Microscope, X-ray powder diffraction, and Vickers Hardness. A total of 80 samples were examined to evaluate the effect of the MWCNTs on the hardness. Results showed a hardness-increasing for the compounds from ~15 % to 24 %. The standard deviation of hardness measures was considered to evaluate the dispersion of MWCNTs in the composites. We applied a linear fit to the hardness data to assess the influence of temperature in the grain consolidation process and variance analysis of data. Results exhibited a substantial dispersion of hardness from 13.13% to 24.57% of error. The analysis of the results obtained at several conditions suggested an optimal setting involving a mixing time of 3 min and a sintering temperature of 760 °C.