【摘要】 采用自行设计的简易压缩成型装置,以粉末粘结工艺,制备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研究。采用扫描电子显微镜(SEM)、排水测密度法、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,所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420 MPa的高压成型过程中无漏料现象发生,特别是材料的致伸缩性能高,无预压应力情况下其饱和磁致伸缩系数达820×10-6,在1 MPa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。更多还原

【Abstract】 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 showed that the composite has 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 is 820×10-6 and 1006×10-6,respectively when 0 MPa and 1 MPa preload-stress is applied.The composite has higher cut-off frequency.The preparation method has 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.更多还原