Atomistic Simulations of Mechanical Properties and Deformation Mechanism of Gradient Nanograined α‐Ti

The tensile deformation behavior of pure titanium (Ti) gradient nanograined (GNG) is investigated based on molecular dynamics simulation. The effects of strain rate and temperature on the mechanical properties as well as deformation mechanism of GNG α‐Ti are systematically investigated. The increase of strain rate rises the tensile strength and decreases the dislocation density and stacking faults in the gradient structure of the material. This is because at higher strain rates, the time available for dislocation nucleation and proliferation is insufficient, delaying the critical point for plastic deformation. Additionally, as temperature increases, both the elastic modulus and tensile strength decrease. This is attributed to enhanced atomic activity and grain boundary migration, which reduce the material's ability to resist dislocation motion. Notably, at elevated temperatures, the material exhibits improved work‐hardening capacity due to significant grain boundary distortion, despite the overall reduction in strength. These findings provide a deeper understanding of the strain rate and temperature‐dependent mechanisms in GNG α‐Ti, which are crucial for optimizing its mechanical performance in practical applications.