Mechanical properties of nanodiamond and multi-walled carbon nanotubes dual-reinforced aluminum matrix composite materials

Nanodiamond (nD) and multi-walled carbon nanotubes (CNT) was used to fabricate reinforced pure aluminum (Al) matrix composites by mechanical ball milling and hot-pressing. Pure Al bulk and each single nanoparticle (nD or CNT) reinforced composites was also fabricated for comparison. Micro-Vickers hardness was measured for single (nD or CNT) and dual nanoparticle (mixture of nD and CNT)-reinforced Al matrix composites and showed maximum values that were approximately six times higher than those of pure Al bulk. Four-point bending behaviors were also discussed and the dual nanoparticles-reinforced Al matrix composites showed highest value of the flexural strength (about 760MPa). The fracture surfaces that resulted from the bending test were also observed. Moreover, the crystallite size and lattice strain of the Al particles in the composites were described by the Scherrer equation.