Empirical Equations for the Magnetization Curve

An empirical equation is derived expressing the permeability in terms of the flux density over an approximate range of 100 to 6,000 gausses. The equation is of the form; ?? = P??^a and is shown to apply to a variety of magnetic materials including certain alloys. Its greatest range appears to be for silicon content electrical sheet steels. A table is given listing the values of the coefficient and exponent for magnetic materials of various grades. Several curves and tables explain the salient features of the method. An extension of the method of derivation to other parts of the magnetization curve indicates their expression by similar laws or equations. Theoretical considerations lead to an hypothesis of four phases of magnetization coupled by three transitional phases for the entire magnetization curve.