Analysis of the irreversible processes of magnetization in steel

Magnetization changes are due to both reversible and irreversible processes. Preisach diagrams can be used to represent irreversible changes but a reversible component must be added to give the total magnetization change. We show that the reversible magnetization component can be separated experimentally by incremental field reversals. It is a function of M, H and the magnetic history. The remaining irreversible magnetization changes can be represented on a Preisach diagram. Experimental and calculated hysteresis loops, using reversible and irreversible components, are shown for a 1 percent Mn steel.