Multiphysics finite element modeling of magnetostrictive devices

Abstract Magnetostrictive materials exhibit changes in magnetization under applied mechanical stress and undergo deformation in response to magnetic fields. This bidirectional magneto-mechanical coupling has enabled a wide range of innovative devices, including actuators, sensors, and energy harvesters. However, their intrinsic multiphysics behavior poses significant modeling challenges, requiring accurate constitutive modeling at the material level and reliable dynamic modeling at the system level. In this work, a convenient and accurate finite element framework is developed by integrating an efficient discrete energy-averaged constitutive model with the commercial COMSOL Multiphysics platform. The primary novelty of this framework lies in three key advancements: the numerical implementation of the discrete energy-averaged model directly within a commercial FE environment, the development of an efficient piecewise linearization strategy for major-loop analysis, and the extension of this framework to encompass complex minor-loop and frequency-domain behaviors. This new model successfully captures hysteretic and frequency-dependent effects, enabling the robust simulation of magnetostrictive devices with complex geometries that remain challenging for conventional analytical methods. The model is experimentally validated using a magnetostrictive terbium–iron–dysprosium unimorph actuator. Simulation results demonstrate accurate predictions of actuator behavior across static, transient, and frequency domains. By providing representative model examples and step-by-step tutorials, this study aims to facilitate the design and prototyping of magnetostrictive devices, thereby accelerating their commercialization and industrial adoption.