Molecular dynamics study of the mechanical behaviour and dislocation evolution in metal–carbon nanotube nanocomposites

This study presents a molecular dynamics investigation of the mechanical behaviour and dislocation evolution in FCC metal nanopillars (Al, Au, Cu, Ni) and their composites reinforced with (8,0) zigzag carbon nanotubes (CNTs). Uniaxial tensile and compressive loading simulations were conducted across a wide temperature range to evaluate the impact of CNT reinforcement on elastic and plastic response. The results show that CNT inclusion significantly enhances Young’s modulus and ultimate tensile strength, particularly at lower temperatures. Dislocation analysis using the Dislocation Extraction Algorithm (DXA) reveals substantial modifications in the nucleation, propagation and interaction of dislocations in the presence of CNTs. In CNT-reinforced systems, dislocation activity is suppressed or delayed, and complex dislocation networks form near the CNT interface. These findings offer valuable insights into nanoscale reinforcement mechanisms and support the design of high-performance, thermally stable metal–CNT nanocomposites.