Tensile stress dependence of the sound velocity in Fe-rich amorphous wires

Abstract

Experimental results concerning the dependence of the longitudinal sound velocity in Fe 77.5Si 7.5B 15 amorphous wires on the tensile stress applied along the length of the wire are reported. We tested Fe 77.5Si 7.5B 15 amorphous wires, 125 μm in diameter, in the as-cast state and after stress–relief process. The measurements were made using the magnetostrictive delay line principle. The obtained results show a strong dependence of the longitudinal sound velocity in the amorphous wire on the applied tensile stress. For a given value of the bias magnetic field, the longitudinal sound velocity increases with increasing the tensile stress value. For about 16 MPa tensile stress and 700 A/m bias magnetic field values, the saturation value of the longitudinal sound velocity is reached.