Enhancement of Mechanical Properties of Carbon Nanotube Reinforced Al Composites Fabricated by Spark Plasma Sintering Using Hot Rolling Techniques

Abstract

Recently much interest has been attracted in replacing heavy metals with light metals such as aluminum to reduce weight to improve fuel efficiency of automobiles. However, weight reduction by light metals often leads to decrease in strength, which causes problems in terms of safety and sustainability. This study aims to produce carbon nanotube (CNT) reinforced aluminum (Al) matrix composites with high performance using a combination of spark plasma sintering (SPS) and hot rolling techniques. Dry ball milling and SPS followed by hot rolling were conducted to uniformly disperse CNT in Al matrix. The microstructures of the composites including dispersibility of CNT were observed using a scanning electron microscope (SEM) and transmission electron microscope (TEM). Anisotropic mechanical behavior was investigated through Vickers hardness and tensile tests. The experimental results demonstrated that the post-sintering hot rolling can highly enhance the tensile strength of the composites.