  With density functional theory, studied are the local magnetic moments in
Fe-Al alloys depending on concentration and Fe nearest environment. At zero
temperature, the system can be in different states: ferromagnetic,
antiferromagnetic and spin-spiral waves (SSW) which has a minimum energy. Both
SSW and negative moment of Fe atoms with many Al atoms around them agree with
experiments. Magnetization curves taken from literature are analysed.
Assumption on percolation character of size distribution of magnetic clusters
describes well the experimental superparamagnetic behaviour above 150 K.

Materials Science