Testing the Applicability of 119Sn Mössbauer Spectroscopy for the Internal Stress Study in Ternary and Co-Doped Ni-Mn-Sn Metamagnetic Alloys

Abstract

The influence of both the Co addition and the internal stress on the atomic level magnetism is comparatively studied in Ni50Mn37Sn13 and Ni45Mn38Sn13Co4 alloys by magnetic measurements and 119Sn Mössbauer spectroscopy. The results show that the saturation magnetization and the hyperfine field follow the same temperature trend. The internal stress state is investigated by subjecting the samples to milling and annealing treatments, and tracking the singlet component revealed by 119Sn Mössbauer spectroscopy. Contrary to what was expected, in the Co-doped Ni-Mn-Sn sample the singlet component can be resolved between the milled and annealed states in both martensite and austenite phases. Therefore, the results demonstrate the feasibility of tracking the singlet component upon the structural recovery in Co-doped Ni-Mn-Sn alloys in a much wider range than in ternary alloys. In addition, it is concluded that the transferred dipolar field at Sn from the neighbor magnetic atoms depends very strongly on the stress field and on the microstructural order surrounding Sn atoms. The observed sensitivity of Sn Mössbauer probe atoms to slight microstructural distortions make 119Sn a powerful technique for the characterization of the stress present in Sn containing metamagnetic shape memory alloys.

Compositional Dependence of Epitaxial L10‐MnxGa Magnetic Properties as Probed by 57Mn/Fe and 119In/Sn Emission Mössbauer Spectroscopy

“…[ 42 ] A similar effect is also observed in other Ni‐based Heusler alloys by means of 119 Sn MS, where the annealing of the strains is closely related with the observed magnetic splitting in Mössbauer spectra. [ 43–45 ] As a result, the recovery of the internal stresses and strains has a major impact on the measured hyperfine parameters in Mn x Ga alloys.…”

Ni-Mn-Sn-Cu Alloys after Thermal Cycling: Thermal and Magnetic Response

“…The X-ray diffraction (XRD, D500 S equipment, Bruker, Billerica, MA, USA) patterns at room temperature were made to verify the crystallographic structure of the spun-ribbons. The refinement of crystalline structures were made by applying the Maud software, which is founded on the Rietveld method [11]. Austenite to martensite direct and inverse temperatures were determined by differential scanning calorimetry (DSC) in a DSC822 Mettler-Toledo calorimeter, at a heating/cooling rate of 10 K/min.…”

“…This trend opens the possibility of deliberate changes in the transition temperatures and benefits while forcing phase transitions by a temperature and magnetic field [9]. The improvement of the magnetic response could be favored by the addition of a magnetic element as Fe [10] or Co [11]. Gd-based and Ni-Mn-In alloys are good candidates for magnetic refrigeration devices.…”

Effect of Cobalt on the Microstructure of Fe-B-Sn Amorphous Metallic Alloys

“…There are, however, only a few studies related to Fe-based MGs that also contain Sn [20,21], presumably due to problems with the production of amorphous structures with higher tin contents. 119 Sn MS was applied to mechanically alloyed Fe-Sn alloys [22,23], to electrodeposited amorphous alloys [24,25], to amorphous Mn-Sn [26], or to Ni-Mn-Sn metamagnetic alloys [27].…”