Magnetostriction of Rare-Earth Metals and Rare-Earth Intermetallic Alloys Based on Iron and Cobalt

The review presents experimental data and their theoretical discussion on anisotropic and volume magnetostriction induced by an external magnetic field in rare-earth metals and their alloys in the region of magnetic phase transitions. The forced magnetostriction was studied above the Curie temperature. From these data, the dependence of the exchange integrals on unit cell volume was obtained. It was also discovered that in the region of magnetic phase transition in rare-earth metals and their alloys, a giant volume magnetostriction takes place. It has been established that in binary RCo2 alloys with a high content of rare-earth metals, a giant volume magnetostriction is caused by an increase in the magnetic moment of the cobalt 3d-sublattice in magnetic fields above the critical value. It is shown that in intermetallics of the R2Fe17 type, giant volume magnetostriction near the Curie temperature region arises due to the strong dependence of the exchange integrals on deformation.