Mössbauer Spectroscopy, Dilatometry and Neutron Diffraction Detection of the e-Phase Fraction in Fe-Mn Shape Memory Alloys

J. MARTINEZ,; G. AURELIO; G. CUELLO; S. M. COTES; A. FERNÁNDEZ GUILLERMET; J. DESIMONI

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Springer Netherlands

Lugar: The Netherlands; Año: 2005 vol. 161 p. 221 - 227

0304-3843

The results of a Mössbauer spectroscopy (MS) and a neutron diffraction (ND) study carried out on a set of Fe?Mn alloys quenched from high temperatures are reported. Upon quenching the high temperature stable phase FCC (gamma) together with metastably retained HCP epsilon) phase are formed. The lattice parameters obtained using ND are in excellent agreement with previous results of the literature. The phase fractions obtained from MS are coincident, within experimental errors, with those extracted from ND, with exception of the case of an alloy with the lowest Mn content (16.8 at.% Mn). That situation can be associated with the occurrence of a high density of stacking faults (SF) in the gamma phase or to the presence of a paramagnetic gamma phase. Epsilon phase fractions obtained from MS and ND decrease smoothly with Mn content but are always larger than the values reported in literature resulting from dilatometry.carried out on a set of Fe?Mn alloys quenched from high temperatures are reported. Upon quenching the high temperature stable phase FCC (gamma) together with metastably retained HCP epsilon) phase are formed. The lattice parameters obtained using ND are in excellent agreement with previous results of the literature. The phase fractions obtained from MS are coincident, within experimental errors, with those extracted from ND, with exception of the case of an alloy with the lowest Mn content (16.8 at.% Mn). That situation can be associated with the occurrence of a high density of stacking faults (SF) in the gamma phase or to the presence of a paramagnetic gamma phase. Epsilon phase fractions obtained from MS and ND decrease smoothly with Mn content but are always larger than the values reported in literature resulting from dilatometry.