Identification of a “thermodynamic consistent” model of magneto-mechanical hysteresis

Smart or multi-functional materials are receiving more and more attention in the last decade, due to their strong potentialities to provide new and remarkable functionalities. With the aim to identify the operator by a systematic approach based on first order reversals, the device reported has been developed. The box contains the magnetostrictive material equipped with a strain sensor based on Fiber Bragg Grating. A screw is also employed to apply a specified prestress to the sample. The availability of an electromagnet with air-gap fields up to 2T allows to apply sufficiently large fields able to lead the Terfenol samples close to saturation, for a wide set of applied pre-stresses. The magnetostrictive response of the Terfenol sample for a wide range of pre-stresses is displayed.