Electron Structure and Microwave Absorbing Ability of Flaky FeSiAl Powders

Soft magnetic metallic materials have been widely used for absorbing electromagnetic wave. Flaky Fe86-tSitAl14 (t=9, 11, 14 and 16) alloys powders were prepared from melt-quenched ribbons by annealing and milling. In a previous report we discussed the order-disordered structure of this alloys. In this article, we studied their electron structure. Covalence electron numbers of (111) and (100) plane increase with increasing Si content but Bohr magneton decreases. Complex permittivity and complex permeability are both decreased with increasing Si content t. The lowest value of reflectivity among the four alloys is originated from Fe70Si14Al14. The peak values of reflectivity are all lower than −10 dB, and the absorbing frequency range (R < −10 dB) increases from 1 to 2 GHz when t reaches 16.