Resonance electromagnetoacoustic method of measuring viscoelastic properties of amorphous ferromagnetic ribbons subjected to low-temperature annealing

Stationary and damped vibrations of the s 0 Lamb mode in a viscoelastic amorphous ferromagnetic ribbon excited upon the electromagnetoacoustic (EMA) transformation have been considered. A resonance method is suggested that employs double EMA transformation for measuring elasticity moduli E and internal friction in amorphous ferromagnetic ribbons. The effect of low-temperature isochronous annealing on the field dependences of Young’s modulus and internal friction of the Fe 80 Si 10 B 10 and Fe 73.7 Cu 1.0 Nb 3.2 Si 12.7 B 9.4 alloys has been studied.