Inverse Hall-Petch Behavior in Nanocrystalline Aluminum Using Molecular Dynamics

This work investigates the mechanical behavior of nanocrystalline aluminum, with special focus on deformation mechanisms, using molecular dynamics simulations an interatomic potential parameterized by authors. To this end, four samples grain sizes ranging from 8,2 to 14,2 nm were constructed, each a volume 15 x 20 nm3. As expected, data tensile tests at strain rate 1,0 109 s−1 showed inverse Hall-Petch relationship. The hardening revealed no significant gain in strength. dislocation analysis indicated that perfect density decreases during testing, while Shockley partials increase. Grain boundary-mediated plasticity was evidenced atomic diffusion along boundaries, as well rotation. Thus, it is concluded conventional plastic mechanisms metals are not preponderant for aluminum.