Effect of Nb Substitution on the Properties of the Fe60Mn10Al30 Alloy

Fe60Mn10Al30-xNbx alloys (2<x<10) prepared by arc-melting technique, were studied by X-ray diffraction, Moessbauer spectrometry and magnetic measurements at room temperature. The Nb substitution induces the presence of a hexagonal Fe2Nb phase in the alloys, in addition to the bcc FeAlMn alloy phase. Both the lattice parameter and the grain size of the bcc phase decrease when the Nb content increases. The obtained Moessbauer spectra result from a magnetic component with broad lines which decreases and an increasing broad paramagnetic component when the Nb concentration increases. The spectra were thus fitted by means of a hyperfine field distribution and a quadrupolar splitting distribution, respectively. It is concluded that the semi-soft character of the Fe-Mn-Al alloy is improved with the Nb substitution of the Al atoms from x=6.