Grain size effect on microstructural properties of 3D nanocrystalline magnesium under tensile deformation

The strength of nanocrystalline (NC) hexagonal closed packed (hcp) magnesium has been studied using computer simulations. Three dimensional NC magnesium materials are developed using Voronoi tessellation in which a random distribution of grains is generated. The microstructural properties and mechanical behaviors under tensile loading are investigated using molecular dynamics simulations. A size scale effect related to the yield stress in the specimen is evidenced. A transition from grain size softening to grain size hardening has been observed for a 10 nm average grain size.