On the structure and magnetic properties of the Fe87MnxSi13-x ribbons

Ribbons of alloys of nominal composition Fe87MnxSi13-x, x=0, 1, 2, were investigated by means of Moessbauer spectroscopy and magnetic measurements. From the spectra, a detailed analysis of short range order and positions of Mn atoms were determined. It was found that the Mn atoms were distributed randomly in as-quenched ribbons. After annealing, manganese left the FeSi matrix apparently. It is assumed that Mn left it by diffusion for grain boundaries or precipitated in an iron poor phase. The magnetic texture of FeSi ribbon is characterized by an isotropic spin orientation distribution but in Mn alloyed ribbons the longitudinal direction is preferred. The changes in magnetic texture as well as the magnetic properties support the idea of interpreting the separation of Mn atoms from the FeSi matrix after annealing. (orig.)