Micromagnetic modeling of magnetization distribution caused by internal twin microstructure of NiMnGa ferromagnetic shape memory alloys

TL;DR

This paper presents a micromagnetic model to analyze how internal twin microstructures influence magnetization distribution in NiMnGa ferromagnetic shape memory alloys, considering magnetic energies and external magnetic fields.

Contribution

It introduces a new micromagnetic free energy model that accounts for twin microstructure effects on magnetization in FMSMAs, advancing understanding of their magnetic behavior.

Findings

Magnetization distribution varies with twin microstructure and external field.

The model predicts local magnetization orientations within twin variants.

Dependence of volume fractions on magnetic field strength.

Abstract

In our present publication we will continue studying the effects of the magnetostatic energy on the magnetization behavior of FMSMAs recently started in some our publications. Our method is based on the direct minimization of our new micromagnetic free energy model of FMSMAs taking into account both the magnetic anisotropy energy and the magnetostatic energy contributions associated with the laminated two-variant twin microstructure. Here, our special interest is to investigate a distribution of local magnetizations within both twin variants, their orientation and their dependence on the external magnetic field and their volume fractions, as well.