Molecular Dynamics Simulation: Influence of Nanotwins on Tensile Strength of α‐Titanium

Abstract This study systematically investigates the influence of twin boundaries on dislocation motion, strength response characteristics under different strain rates, and the regulatory effects of twin density and distribution on macroscopic mechanical properties using molecular dynamics (MD) simulations. The results reveal that the high yield strength of the {11‐21}<11‐26> nanotwin model arises from the combined effects of strong interfacial obstruction, slip system restriction, full dislocation‐dominated deformation mechanisms, and polycrystalline synergy. At room temperatures, reduced thermal vibrational energy requires dislocations to overcome higher local atomic stress barriers. Elevated temperatures induce atomic stress relaxation and interfacial softening, leading to reduced average stress. Under high strain rates, stress distribution diffuses into grain interiors, whereas low strain rates concentrate atomic stress peaks at twin boundaries and dislocation pileup fronts. These findings provide theoretical insights for designing high‐strength, high‐toughness titanium alloys and advance nanotwin engineering in extreme‐environment materials.