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When Fe3Sn powders were milled for 30 h, the X-ray diffraction pattern of the as-milled powders revealed a broad peak typical for an amorphous phase. Nanocrystals appeared after 30-h milling for Al-doped Fe3Sn powders and the amount of nanocrystals increased with the increase of the amount of aluminum doped. Owing to the formation of nanocrystals, the saturation magnetization of the as-milled powders increased with Al doping. However, the coercivity exhibited an opposite tendency compared with the saturation magnetization. The crystalline phases were obtained by annealing as-milled powders at 800°C for 0.5–5 h. The crystalline Fe3Sn phase was formed for an Al (3.63 wt%)–Fe3Sn sample after 0.5-h annealing with a saturation magnetization of 105 emu/g.

The coercivity of the as-milled samples had a maximum value of 90 Oe for 33.9 wt%Zn. When annealed at 400° C for 10 days, the metastableεphase, and Γ and Γ1phases appeared with 9.75 wt%Zn, and 33.7 wt%Zn, respectively. The α-Fe phase disappeared at 73.3 wt%Zn, causing the saturation magnetization to decrease drastically to 2 emu/g. The precipitation of the metastableεphase in the annealed samples containing 24.2 wt%Zn had a maximum coercivity of 175 Oe. A single α-Fe phase is obtained upon solution treatment at 800° C for 1 h. After aging, precipitation of theεphase occurred for Zn content above 6.74 wt%. The saturation magnetisation and the coercivity of aged samples were larger than those of solution-treated samples.