TY - JOUR
T1 - Mössbauer spectroscopy studies on magnetic properties for57Fe-substituted Ni-Mn-Sn metamagnetic shape memory alloys
AU - Umetsu, Rie Y.
AU - Sano, Kenji
AU - Fukushima, Kouji
AU - Kanomata, Takeshi
AU - Taniguchi, Yusuke
AU - Amako, Yasushi
AU - Kainuma, Ryosuke
N1 - Publisher Copyright:
© 2013 by the authors; licensee MDPI, Basel, Switzerland.
PY - 2013/6/1
Y1 - 2013/6/1
N2 - In order to investigate the Fe substituted effects on the magnetic properties of the Ni-Mn-Sn metamagnetic shape memory alloys, magnetization and the Mössbauer spectroscopy measurements were carried out with using 57Fe-doped specimens of Ni2Mn1.48−x57FexSn0.52 (x = 0.02, 0.04 and 0.08). Singlet-type Mössbauer spectra were clearly observed for x = 0.02 and 0.04 just below the martensitic transformation temperature, TM, and above the Curie temperature, TC, in the austenite phase. It was clear that the magnetic state in the martensite phase just below TM was paramagnetic for x = 0.02 and 0.04. In further doped57Fe to Ni2Mn1.48Sn0.52, TC in the austenite phase slightly increased. However, the value of TM significantly decreased. As a result, martensite phase with small spontaneous magnetization directly transformed to the ferromagnetic austenite phase during heating for x = 0.08. These results obtained from the Mössbauer spectra were consistent with the results of the magnetic measurements in this study and the phase diagram reported by Fukushima et al. for normal Fe-doped Ni2Mn1.48−xFexSn0.52 alloys. The breakdown of the general rule, in which the ferromagnetic shape memory alloys with larger value of the valence electrons per atom, e/a, showed higher TM, was also appeared in Ni2Mn1.48−xFexSn0.52 alloys, being similar to Ni2Mn1−xFexGa alloys.
AB - In order to investigate the Fe substituted effects on the magnetic properties of the Ni-Mn-Sn metamagnetic shape memory alloys, magnetization and the Mössbauer spectroscopy measurements were carried out with using 57Fe-doped specimens of Ni2Mn1.48−x57FexSn0.52 (x = 0.02, 0.04 and 0.08). Singlet-type Mössbauer spectra were clearly observed for x = 0.02 and 0.04 just below the martensitic transformation temperature, TM, and above the Curie temperature, TC, in the austenite phase. It was clear that the magnetic state in the martensite phase just below TM was paramagnetic for x = 0.02 and 0.04. In further doped57Fe to Ni2Mn1.48Sn0.52, TC in the austenite phase slightly increased. However, the value of TM significantly decreased. As a result, martensite phase with small spontaneous magnetization directly transformed to the ferromagnetic austenite phase during heating for x = 0.08. These results obtained from the Mössbauer spectra were consistent with the results of the magnetic measurements in this study and the phase diagram reported by Fukushima et al. for normal Fe-doped Ni2Mn1.48−xFexSn0.52 alloys. The breakdown of the general rule, in which the ferromagnetic shape memory alloys with larger value of the valence electrons per atom, e/a, showed higher TM, was also appeared in Ni2Mn1.48−xFexSn0.52 alloys, being similar to Ni2Mn1−xFexGa alloys.
KW - Austenite phase
KW - Heusler alloy
KW - Martensitic transformation
KW - Metamagnetic shape memory alloy
KW - Mössbauer spectroscopy
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U2 - 10.3390/met3020225
DO - 10.3390/met3020225
M3 - Article
AN - SCOPUS:84969563036
VL - 3
SP - 225
EP - 236
JO - Metals
JF - Metals
SN - 2075-4701
IS - 2
ER -