Amorphous and nano-crystalline soft magnetic materials

Abstract

This chapter discusses the advent of nano-crystalline and amorphous soft magnetic materials and their properties and production methods. The magnetic material is produced commercially in the form of ribbon much thinner than any electrical steel, so eddy currents are naturally low under a.c. excitation. This, combined with inherent large resistivity, leads to low losses. No grain boundaries are present to impede domain wall motion, so hysteresis losses are low and very high permeability can be achieved. It was soon recognised that amorphous ribbon was indeed an exciting new class of engineering material which not only could replace conventional soft magnetic materials in many applications but could also satisfy magnetic requirements in entirely new applications.