On the relationship of reversible and irreversible processes during magnetization and magnetization reversal of ferromagnetic materials

Curves corresponding to the normal magnetization curve and the back of the hysteresis loop and separately reproducing reversible and irreversible processes of magnetization and reversibly irreversible changes in the magnetization during maximum minor hysteresis cycles were constructed. For specimens of steel 75Γ hardened and tempered to 300°C, generalized expressions for curves that reproduce relationships between different components for the demagnetization portion of the hysteresis loop were obtained; for specimens hardened and tempered to 600°C, individual expressions for portions of the magnetization-reversal curve of the steel in fields from 0 to −2Hc were obtained. The dependences of the relative irreversible and reversible fractions of saturation magnetization on the tempering temperature were analyzed. The maximum reversible component of the saturation magnetization, i.e., the difference Ms-Mr, was shown to be a suitable parameter for quality control of tempering.