高性能粘结超磁致伸缩复合材料的制备与性能表征

采用自行设计的简易压缩成型装置，以粉末粘结工艺，制备了环氧树脂粘结超磁致伸缩材料。对设计制造的成型模具及粘结超磁致伸缩材料的制备工艺及性能进行了研究。采用扫描电子显微镜（SEM）、排水测密度法、Agilent 4294A动态阻抗分析仪、电子万能试验机以及电阻应变片技术，表征了采用该装置和工艺制备的粘结超磁致伸缩材料的显微组织结构、密度、高频响应、力学性能、磁致伸缩及压应力特性。结果表明，采用该装置和工艺制备的粘结超磁致伸缩材料，组织均匀致密，气孔率低，性能重复性好，在420MPa的高压成型过程中无漏料现象发生，特别是材料的致伸缩伸缩性能高，无预压应力情况下其饱和磁致伸缩系数达820×10-6，在1MP压应力下其饱和磁致伸缩系数高达1006×10-6，同时该材料具有较高的截止使用频率。该制备方法具有成本低、成型设备及工艺简单、容易操作及产品性能高等优点，适合于工业生产。对复合材料性能改进的机理进行了阐述。

The preparation and characterization of polymer-bonding giant magnetostrictive composites

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.