Magnetic and structure phase transitions investigated by standing magnetoelastic waves

The theory of the experimental apparatus used for producing and revealing magnetomechanical waves, was elaborated. It was demonstrated that, in the investigated case, the measured amplitude of the elastomagnetic waves is a function of the reversible permeability as well as the elastic and piezomagnetic coefficients. All the last parameters are sensitive to both structure changes and magnetic interaction variations. Therefore during the heat treatment the magnetoelastic wave amplitude is a physical sensor with which we can investigate phase transitions. On this basis the effects of the structural relaxation, the ferro-paramagnetic state transition and the amorphous-crystalline structure development, were investigated in samples of metallic glass.