Aluminium Composite Materials Possessing Magnetic Properties Produced by MA-SPS Process

In order to fabricate the Al-based composite materials possessing magnetic properties, air-atomized pure aluminium powder together with Ni-Cu-Zn Ferrite (FR) powder was mechanically alloyed (MAed) using a vibrational ball mill, and the MAed composite powders were consolidated into bulk materials by spark plasma sintering (SPS). Changes in constituent phases, particle size, hardness and soft magnetic properties of both the MAed powders and SPS materials were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), hardness measurements and vibrating sample magnetometry (VSM), respectively.No solid-state reactions could be detected by XRD in the MAed powders. The Vickers microhardness of the MAed powders increased by increase in MA time. The saturation magnetic flux density for the MAed powders were found to depend only upon the amount of the FR powder present. Ni-Cu-Zn Ferrite was decomposed to form ZnO when the MAed powder was sintered at 673 K and 773 K by SPS, whereas Al13Fe4 and Al4C3 were detected when the MAed powder was sintered at 873 K. The highest saturation magnetic flux density was obtained when the MAed powder were consolidated at 773 K.