Molecular dynamics studies of CNT-reinforced aluminum composites under uniaxial tensile loading

Abstract

This paper investigates the mechanical behavior of carbon nanotube (CNT)-reinforced aluminum composites (CNT-Al composites) under a tensile loading condition using molecular dynamics (MD) simulations. A review of current computational and experimental studies highlights the benefits of CNT-Al composites from a structural point of view. However, quantitative and qualitative investigations on the improvements due to the inclusion of CNTs are still rare. This study shows that, compared to pure aluminum, the Young's moduli are improved by 31% for (4,4)CNT-Al, 33% for (6,6)CNT-Al, and 39% for (8,8)CNT-Al. Moreover, the corresponding toughness values are significantly enhanced by 37%, 72%, and 100%. Furthermore, the MD simulations provide insights into various fracture behaviors at the atomic scale, including lattice disordering, local changes in lattice structures due to stacking faults, and void nucleation/growth. The component analysis shows that the mechanical properties of CNT-Al composites improve significantly, even with a small amount of CNT, due to the considerable load-bearing capacity of CNT.