Dynamic multiaxial behaviors of 3D shape memory alloy nanowires: A phase-field study

This article focuses on the dynamic multiaxial behaviors of shape memory alloy (SMA) rectangular prismatic nanowires. A strain-based order parameter 3D phase-field model is used to study microstructure evolution and consequent thermo-mechanical behaviors in the cubic-to-tetragonal transformations in SMA nanowires. The FePd nanowire is subjected to axial-transverse and axial-torsion loadings paths. The numerical results demonstrate the strong influence of multiaxial loadings on microstructures and thermo-mechanical response. The variation of thermo-mechanical response stems from the nucleation of energetically favorable martensitic variants to the applied loading. The understanding of multiaxial thermo-mechanical response of nanowires is essential in developing better SMA-based devices.