EFFECT OF INTERNAL STRESS DISTRIBUTION ON MAGNETOMECHANICAL DAMPING

Magnetomechanical damping in ferromagnetic materials has its source in stress-driven irreversible movement of magnetic domain boundaries. The maximum damping is proportional to λsE/σi, where λs is the saturation magnetostriction, E is Young's modulus, and σi is the average internal stress opposing domain boundary motion. In order to obtain the stress dependence of the damping, we include a distribution of internal stresses over a range ±Δσ i about the average value. Inclusion of this distribution yields a theory in good quantitative agreement with experimental results for samples of 4% SiSingle Bond signFe and cast iron. © 1968 The American Institute of Physics.