Magnetic Incremental Permeability of Elastically Deformed Iron and Nickel

Abstract

Abstract The field dependences of the magnetic incremental permeability U~(H) have been measured on nickel and iron subjected to both elastic compression and tension. The inflections and additional maxima on the U~(H) curves are observed for nickel under tension and for iron under compression. The appearance of the features on the U~(H) curves is traceable to the induction of magnetic texture of the "easy-plane" type caused by elastic deformation of nickel and iron samples. These features appear only if the signs of magnetostriction and applied load are opposite. Only in this case, there is the possibility of estimation of applied mechanical stresses and residual stresses (after annealing). This can be useful for technical diagnostics of objects made of ferromagnetic materials with different signs of magnetostriction. The proposed technique is makes it possible to estimate the “easy-axis” magnetostriction constant.