An analysis of the factors affecting strengthening in carbon nanotube reinforced aluminum composites

Micromechanics models applied to Al–CNT composites are evaluated for their applicability with respect to CNT concentration and processing technique. Rule of mixtures is effective in predicting the elastic modulus for low CNT content (5 wt.%) and with poor dispersion. Tensile strength data of Al/CNT composites from the literature is analyzed to understand the effects of CNT dispersion, processing technique, degree of deformation and CNT–matrix interface on the elastic modulus, strength and toughness of composites. Strengthening can be divided in three regimes which show decreasing strengthening effect with an increasing CNT content. The strengthening is highest for CNT content less than 2 vol.%. The applicability of the micromechanics models in predicting the strength and elastic modulus of CNT reinforced metal matrix composites is also analyzed. The rule of mixtures is effective in predicting the elastic modulus of the Al/CNT composites for low CNT content (