Polymer-matrix giant magnetostrictive composites were prepared by combining Tb0.30Dy0.7Fe1.95 / epoxy and making use of home-made and simple compression molding device. The bonding process and the structure of the molding device were introduced. The properties of the composites were studied. The microstructure, density, high-frequency responsing property, mechanical property, magnetostriction and compressive stress effect were characterized by the scanning electronic microscope (SEM), Archimedes displacement method, Agilent 4294A dynamic impedance analyzer, YE-300 type of electronic universal testing machine, standard strain gauge technique respectively. The results show that the composite had many advantages such as homogeneous and compact microstructure, low porosity, high magnetostriction, good property reproducibility and so on. The raw materials were not ejected out off the mould chamber during the molding process. The magnetostriction of the composite was 820×10-6 and 1006×10-6 respectively when 0MPa and 1MPa preload-stress was applied. And the composite had higher cut-off frequency. The preparation method had lots of advantages such as low cost, simple device and process and high properties and so on, and appropriate for industrial applications. The property improving mechanism of the composites was explained.
