| Magnetoelastic properties of cold rolled terbium-dysprosium, alloys were investigated. Magnetostrictive strains at fields of 4.5 kOe and strains of up to 34 MPa were measured for samples of varying deformations and annealing times. Up to 55% of single crystal magnetostriction was observed for heavily deformed samples. Correlations between crystalline texture and magnetostriction were made by relating saturation strain to thermal expansion anisotropy and grain orientation distributions. Greater linear magnetostrictive strains were observed for samples exhibiting more pronounced texture. In addition, magnetomechanical damping effects of polycrystalline TbDy were determined through stress-strain measurements. Up to fivefold reductions of elastic moduli below the Curie point and mechanical energy dissipation of up to 23% per cycle were observed. Our data and analysis suggest a prominent role for the microstructure of grain orientations and grain boundaries in the magnetic damping properties of polycrystalline ThDy alloys. |
