Spin alignment and related properties of BCCCr-Fe-Mn system

Magnetic properties of the Cr-rich BCC Cr-Mn-Fe system are reported. Mossba uer spectroscopy with circularly polarised source allowed one to determine the Fe magnetic moment's component parallel to the applied field. These mea surements combined with magnetisation measurements and standard Mossbauer s pectroscopy reveal that the main contribution to the magnetisation at low t emperature is due to the Fe moments. Their values vary from about 0.7 mu (B ) to about 1 mu (B). The directions of iron moments also vary in space even in an external field of I T. The angular disordering of Fe magnetic moment s increases with decreasing Fe concentration. A part of the Fe atoms, namel y the ones surrounded by eight Cr atoms as a nearest neighbours, exhibits a low magnetic moment. These moments are completely disordered and do not co ntribute to the measured magnetisation. Cr and Mn atoms contribute to the n et magnetisation (in the applied field of IT). This contribution amounts to 0.03 to 0.20 VB per atom. The value of the Cr and Mn total contribution to the magnetisation depends linearly on the Fe concentration and is clearly uncorrelated with the concentration of Mn, which shows that Cr and Mn give similar contributions to the magnetisation. (C) 2001 Elsevier Science B.V. All rights reserved.