Steel restructured

Glass-like steels offer most of the advantages of the more conventional material but with some important bonuses in magnetic terms. If suitable ´glass-forming´ alloys are rapidly quenched at around 10⁶°C/s from the liquid to solid state, thin ribbon material with excellent magnetic properties is formed. Because the resulting ribbon is amorphous it has no crystal boundaries and only a few defects which impede the motion of magnetic domain walls when the material is placed in a magnetic field. This means that material with very low magnetic losses and high permeability can be produced. The amorphous ribbon has the major advantage of low losses because its high resistivity and thinness produce small eddy current losses and its lack of structural defects makes its hysteresis loss low. The author discusses the properties of these steels and their application to transformer cores. The losses and the economics associated with the use of such steels are discussed