Characterization of cubic tumbler rod milled dispersed carbon nanotubes–Aluminum composites

Abstract

In this work, cubic tumbler rod milling was used to disperse X wt% multiwalled carbon nanotubes (X = 0.5, 0.75, 1.0) in an aluminum matrix. Dispersed precursor of aluminum–multiwalled carbon nanotube composite was subsequently consolidated by cold compaction followed by sinter-forged process. Microstructural and mechanical behaviors of as-produced aluminum–multiwalled carbon nanotube composites with different concentration were investigated. Findings revealed that the as-produced Al–0.75 wt% carbon nanotube sinter-forged composite exhibits homogenous distribution and embedded nanotubes confirmed by the scanning electron microscope and the properties were observed to be increased significantly up to addition of 0.75 wt% of carbon nanotubes concentration than the pure aluminum as well as extruded composite and decrease to 1.0 wt% carbon nanotube due to the agglomeration of multiwalled carbon nanotube. However, enhancement of hardness, tensile strength, and Young’s modulus of the nanocomposites, compared with pure aluminum are 48.5, 83.8, and 30%, respectively. The tensile fractography of sinter-forged composite shows carbon nanotubes act like a bridge and barring the crack growth of aluminum matrix, remaining are pullout. Hence, it can be concluded that aluminum carbide phase starting from 0.75 wt% carbon nanotube and a strong interfacial bonding in as-produced aluminum–carbon nanotube composite has been observed which gives effective load transfer between aluminum matrix and carbon nanotubes.