Instability analysis of an electro-magneto-elastic actuator: A continuum mechanics approach

The study of advanced artificial electro-magneto-elastic (EME) materials recently connects the material science with the electrodynamics. In particular, EME materials established a new research direction, which provides the fruitful ideas for the advanced engineering and medical field applications. In the present paper, we introduce a continuum mechanics-based method to analyze an electro-magneto-mechanical instability (EMMI) phenomenon of a smart actuator made of an EME material. The proposed method is based on the nonlinear theory of electro-magneto-elasticity followed by the second law of thermodynamics. We develop an analytical EMMI model for a smart actuator through a new amended energy function. This amended energy function accounts the electro-magnetostriction phenomenon for a class of an incompressible isotropic EME material. Additionally, the amended energy function successfully resolves the physical interpretation issue of the Maxwell stress tensor in large deformation. The formulated continuum mechanics-based EMMI model is also compared and validated with an energy-based EMMI model existing in the literature.