Amorphous magnetic materials for transducers

The magnetic and magnetoelastic properties of melt spun rare earth based amorphous and nano-crystalline alloys have been measured with a view to their eventual application as high frequency active transducer elements. Strains in the region of 1500 ppm at low temperatures and low fields decreasing to ∼ 600 ppm at room temperature have been observed for amorphous ribbons. However, larger strains have been measured. ∼ 2000 ppm at room temp., for nanocrystalline samples still displaying coercivities (30kA/m) less than their fully crystalline counterparts.