K. Frydrych | Searcharxiv

arXiv2026

Influence of Manganese Content on Plastic Deformation Mechanisms in Polycrystalline {\alpha}-Ti-Mn Alloys

Titanium alloys are widely used in aerospace, biomedical, and energy applications owing to their high specific strength, corrosion resistance, and biocompatibility. Among them, $\alpha$-titanium alloys with a hexagonal close-packed (hcp) crystal structure exhibit characteristic deformation mechanisms governed by crystallographic slip and defect evolution. In this study, the influence of manganese content on the plastic deformation mechanisms of polycrystalline $\alpha$-Ti-2Mn and $\alpha$-Ti-4Mn (at.%) alloys is investigated using molecular dynamics simulations. Atomistic models were subjected to uniaxial loading at room temperature at a strain rate of 10$^9$ s$^{-1}$. The mechanical response was evaluated through stress-strain behavior, structural evolution, dislocation nucleation and interaction, and analysis of the local deformation field. Plastic deformation in these $\alpha$-Ti-Mn alloys is dominated by dislocation nucleation and their subsequent evolution within the hcp lattice. Increasing Mn content leads to higher stress levels and enhanced resistance to plastic deformation, accompanied by changes in dislocation activity and defect evolution.

cond-mat.mtrl-sci↗

arXiv2022

Multiscale nanoindentation modeling of concentrated solid solutions: A continuum plasticity model

Recently developed single-phase concentrated solid-solution alloys (CSAs) contain multiple elemental species in high concentrations with different elements randomly arranged on a crystalline lattice. These chemically disordered materials present excellent physical properties, including high-temperature thermal stability and hardness, with promising applications to industries at extreme operating environments. The aim of this paper is to present a continuum plasticity model accounting for the first time for the behaviour of a equiatomic five-element CSA, that forms a face-centered cubic lattice. The inherent disorder associated with the lattice distortions caused by an almost equiatomic distribution of atoms, is captured by a single parameter {\alpha} that quantifies the relative importance of an isotropic plastic contribution to the model. This results in multiple plasticity mechanisms that go beyond crystallographic symmetry-based ones, common in the case of conventional single element metals. We perform molecular dynamics simulations of equiatomic CSAs: NiFe, NiFeCr, NiFeCrCo, and Cantor alloys to validate the proposed continuum model which is implemented in the finite element method and applied to model nanoindentation tests for three different crystallographic orientations. We obtain the representative volume element model by tracking the combined model yield surface.

physics.comp-ph↗