Reversible and irreversible magnetization behavior in SmCo films

Recent studies of demagnetization processes in permanent magnets have used two different methods for determining the reversible magnetization, often a rriving at conflicting results. In the present work, enhanced-remanence SmC o films have been prepared by DC magnetron sputtering. The evolution of the reversible (M-rev) and irreversible (M-irr) magnetization along the initia l magnetization curve and the demagnetization curve of the films was determ ined using the two methods. In one case, the DCD definition of the reversib le magnetization was used to measure the quantity from a set of recoil curv es. Alternatively, the moving Preisach model was used to separate the magne tization into its components M-rev and M-irr. We discuss the different beha viors encountered for the reversible magnetization and the inter-relation f unction eta = (delta/M-rev/delta M-irr)(Hi) and interpret the differences. (C) 2000 Elsevier Science B.V. All rights reserved.