Iron losses at high magnetic flux densities in electrical sheet steels

The paper describes a thermal method of measuring iron losses in sheet materials which may be used at any flux density. The method is used to measure the total iron losses at 50c/s in a number of silicon-iron materials and in one sample of cobalt iron up to an approximate induction of 2.4Wb/m2. The hysteresis component of the loss, obtained by subtracting the calculated eddy-current loss, is found in all cases to reach a saturation value at high densities. Empirical formulae are given which aim at giving the loss at high inductions from a knowledge only of the losses at lower densities.