Mechanical and magnetic properties of a novel polymer infiltrated directionally solidified RE-Fe giant magnetostrictive materials

Newly developed polymer infiltrated grain aligned composite Terfenol-D has the advantages of maintaining the favorable crystal orientation of the directionally grown RFe₂ phase. In order to infiltrate the polymer effectively, it is necessary to prepare composition with a low Fe content (0.64≤y≤1.7) in Tb_0.33Dy_0.67Fe_y. With decreasing Fe content, the amount of the eutectic phase increases which can be removed by annealing. This composite shows many improved properties compared with conventional composite or monolithic Terfenol-D material. Through this new material, high magnetostrictive strain can be obtained under relatively low magnetic field. In addition, it shows a considerably higher modulus of rupture of around 65∼92 MPa in four-point bend test.