Altering magnetostrictive strain pathways via morphology of spontaneously aligned domains

Zhang

et al. 2014

Chinese Phys. B

A simplified quasi-static computational model for self-sensing applications of magnetostrictive actuators based on terfenol-D rods is presented. Paths and angle changes in the magnetic moments rotation of Tb0.3Dy0.7Fe2 alloy are studied as functions of compressive stress and magnetic field, and then used to determine the magnetization in its actuation. Then sensing of magnetic induction picked from a driving coil in an actuator is derived. The model is quick and efficient to solve moments rotation and its magnetization. Sensing results of compressive stress and magnetostriction calculated by the model are in good agreement with experiments and will be helpful in the design and control of self-sensing applications in actuators.

Section: Magnetization Calculation Of Domains Rotationmentioning

confidence: 99%

Modelling self-sensing of a magnetostrictive actuator based on a terfenol-D rod

Zhang

et al. 2014

Chinese Phys. B

Induced additional anisotropy influences on magnetostriction of giant magnetostrictive materials

Journal of Applied Physics

2012

Initial magnetization realignments induced by a uniaxial compressive pre-stress or transverse magnetic annealing can enhance effectively strain output of giant magnetostrictive materials. However, differing from the use of stress that induces in-plane anisotropy, it is found that magnetic annealing is capable of resulting in a uniaxial magnetic anisotropy in 〈110〉 grain-aligned TbDyFe polycrystals. We find the critical induced additional anisotropy to generate a uniaxial magnetization alignment along only one easy axis that is essential to realize 90° domain evolution during initial magnetization stage, hence yielding a large magnetostriction under modest switching fields. By a phenomenological approach based on magnetization rotation, we explain quantitatively how the induced additional anisotropy energy influences the magnetostrictive behaviors under coupled magnetomechanical loadings. Consequently, distinctive approaches to further enhance the saturation magnetostriction are suggested through the combination use of induced additional anisotropy and compressive pre-stress.

Effect of the induced anisotropy axis on altering domain alignment and magnetostriction of Terfenol-D

Sun

Applied Physics Letters

2014

The present work investigates quantitatively the effect of induced anisotropy axis on magnetostriction of Terfenol-D, exploring a possible method of tailoring flexibly magnetostriction for a particular purpose. It is found that the induced anisotropy axis shows significant effect on the initial domain state, magnetization process, and thus the magnetostriction. Magnetostriction behaviors for a specific induced anisotropy axis are discussed and compared with the experimental observations. The critical case for the expected 90° domain alignments has been also analyzed quantitatively. Diagrams of domain state evolutions are established, shining some light on understanding magnetostriction tunability and developing magnetostrictive material.