Enhanced young's moduli and damping capacity in magnetically annealed Tb_0.36Dy_0.64(Fe_0.85Co_0.15) ₂ polycrystals

The magnetomechanical performance of ferromagnets is strongly sensitive to their initial magnetic states. In this work, magnetomechanical properties of the 〈1 1 0〉 oriented crystals Tb_0.36Dy_0.64(Fe _0.85Co_0.15)₂ with different initial magnetic states induced by field annealing have been studied. Young's moduli and damping capacity were calculated from stress-strain curves taken by quasi-static measurements. The sample became 'harder' after perpendicular magnetic annealing, possessing much larger Young's modulus than the untreated one. In addition, the maximum damping capacity ΔW/W for the magnetically annealed rod reached 1.176 at a stress magnitude of 21.2 MPa, both of which were higher than that of the untreated sample. The variation of Young's moduli and damping capacity can be explained by the magnetic domain switching process and movements of non-180° domain walls.