Amorphous Magnetoelastic Materials

Abstract

AbstractThe outstanding feature of amorphous magnetoelastic alloys is the controllability of the magnetic anisotropy energy, Curie point, magnetostriction and magnetic moment. This control of material characteristics, achieved by magnetic and stress annealing plus changes incomposition, is impossible in crystalline materials. The control allows the design of tactile and magnetic field sensors with special features and very high sensitivity. The materials discussed are prepared by rapid solidification through melt spinning in ribbon and wire geometries and magnetron sputtering onto substrates. As an example of the advantagesof sputtered material, an accelerometer on silicon micro-cantilevers is shown. I-t has nocoils. The basic magnetoelastic theory that governs tactile sensors is shown. Low-noise magnetic field sensors with novel twist anisotropies and Barkhausen instabilities in wiresare discussed.