Magnetic state of quasiordered Fe–Al alloys doped with Ga and B: magnetic phase separation and spin order

Results of structural, magnetic, and Mössbauer studies of quasi ordered alloys Fe$_{65}$Al$_{35-x}M_{x}$ ( $M_x$ = Ga, B; $x$ = 0, 5 at %) are presented. The magnetic state of examined structurally–single-phase alloys at low temperatures is interpreted from the viewpoint of magnetic phase separation. An explanation is proposed for the observed behavior of magnetic characteristics of Fe$_{65}$Al$_{35}$ and Fe$_{65}$Al$_{30}$Ga$_{5}$ in the framework of the model of two magnetic phases, a ferromagnetic-type one and a spin density wave. The boron-doped alloy Fe$_{65}$Al$_{30}$B$_{5}$ is shown to demonstrate behavior that is typical of materials with the ferromagnetic type of ordering.