Features of Internal Friction in Ferromagnets

Abstract

Based on the application of two model descriptions proposed by A.A. Rodionov, it is shown that description of internal friction of magnetic materials in various magnetoelastic states subjected to alternating elastic fields should consider not only the magnetic component but also the non-magnetic component along with its changes in the presence of the magnetic field.
 The magnetic component of internal friction is associated with the movement of domain boundaries (DG) (hysteresis attenuation (amplitude-dependent — irreversible displacements of DG)) and amplitude-independent (reversible displacements of DG without separation from the fixing points) with reversible and irreversible rotations of spontaneous magnetization vectors.
 The non-magnetic component is determined by several components, all of which can dominate over a particular region of frequencies, temperatures, external influences, and initial structural states of the system under study. It depends on the type of defects, their concentrations, and spatial and orientation distribution in crystals.
 The paper proposes an approach to separate the internal friction in magnetic materials into magnetic and non-magnetic components which can be extended to materials with domains and domain boundaries including antiferromagnets, ferroelectrics, ferromagnets, etc.
 This approach leads to an expansion of the previously used ideas about the method of separating the magnetic component from the recorded spectrum of internal friction.