| Recently, in accordance with rapid progress of wireless telecommunication technology, the electromagnetic interference of high frequency is recognized as one of the serious problems between electronic and digital equipment. The Fe-Si-Al soft magnetic alloys are suit for anti high frequency electromagnetic interference due to their low magnetocrystalline anisotropy, near zero magnetostriction, high permeability under the weak magnetic field and large resistivity.In this dissertation, the Fe-Si-Al flakes that have a large aspect ratio have been prepared using high energy ball milling and annealing. The microstructure, soft magnetic properties and high-frequency properties of samples with different technical parameters were studied systematically using SEM, XRD, SQUID and MTG respectively. The high frequency properties of the toroidal samples made from the flakes mixed with proper epoxide resin were measured by impedance analyzer. The effect of add Ti into the alloys was also discussed in this dissertation.The flake was obtained usingΦ3mm stainless steel ball and the ball-to-power mass ratio of 3:1. The aspect ratio of the flake is large than 15 after ball milled for 50 hours. During ball milling, the grain size decreased and the internal strain increased. The ordered DO3 superlattice coexisting withα-Fe matrix vanished with prolong milling, but recovered after annealing at 500℃for 30 min.The soft magnetic properties deteriorated during ball milling. The permeability of the toroidal samples keeped steady when the frequency was under 1 GHz. The saturations magnetization of the flakes can be improved by annealing at 500°C for 30min, and the coercivity was reduced. The toroidal samples made of the annealed flakes exhibited higher permeability, but the cutoff frequency was declined a little.(Fe100-xTix)85Si9.6Al5.4 (wt%) (x = 0, 1, 2, 3, 4) alloy ribbons was prepared using melt spinning. It is found that Ti doped can reduce the milling time and improve the high frequency properties.
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