Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.2320/matertrans.MT-MG2022014

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.7566/JPSCP.38.011138

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DOI： 10.7566/JPSCP.38.011139

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Bioelectromagnetics  

Pseudogout is crystalline arthritis. It has a similar clinical picture to that of gout, and it is difficult to distinguish the two diseases using conventional analysis methods. However, it is important to identify the different crystals responsible for these two cases because the treatment strategies are different. In a previous study, we reported magnetic orientation of monosodium urate (MSU) crystals, which are the causative agent of gout, at the permanent magnet level. In this study, we investigated the effect of an applied magnetic field on calcium pyrophosphate (CPP) crystals, which are the causative agent of pseudogout, and the difference in the magnetic responses of CPP and MSU crystals. We found that the CPP crystals were oriented in a magnetic field on milli-Tesla order because of the anisotropy of the diamagnetic susceptibility. In addition, the CPP crystals exhibited different anisotropic magnetic properties from those of MSU crystals, which led to a characteristic difference between the orientations of the two crystals. That is, we found that the causative agents of gout and pseudogout responded differently to a magnetic field. This report suggests that the discrimination between CPP and MSU by optical measurements is possible by application of magnetic fields appropriately. © 2023 Bioelectromagnetics Society.

DOI： 10.1002/bem.22444

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PubMed

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.jmmm.2022.170000

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.jmmm.2022.169295

Authorship：Lead author,　Corresponding author   Language：Japanese   Publisher：Journal of the Physical Society of Japan  

First-principles calculations show that the atomic disorder between Al and Ge does not destroy the half-metallic character of CrAlGe, and that its unique character is, however, destroyed by the swap between Cr and Al (or Ge). Our analysis of the X-ray diffraction patterns of CrAlGe indicates the existence of this swap disorder.

DOI： 10.7566/JPSJ.91.064706

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.jmmm.2021.168908

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.2355/isijinternational.ISIJINT-2021-404

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.jallcom.2021.161310

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.jmmm.2021.168411

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jallcom.2021.161310

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© 2020 The Japan Institute of Metals and Materials. Ferromagnetic MnAlC (¸-phase) can be synthesized by a single-route conventional reactive sintering method. The maximum magnetization and coercivity were 75.8 Am2/kg and 57 mT, respectively. The ¸-phase fraction was evaluated to be 81 mass% for Mn55Al45C2 annealed at 1273 K. The ¸-phase of Mn55Al45C2 can be synthesized at an annealing temperature from 873 to 1273 K, whereas that of Mn55Al45 cannot be synthesized. It was indicated that the phase stability of the hcp-phase (¾-phase) was improved by adding carbon, resulting in an ¾¸ transformation.

DOI： 10.2320/matertrans.MT-M2020166

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Metals and Materials  

Substrate heating effects on the microstructure and magnetic properties of MnAlGe films grown on Si/SiO2 substrate by sputtering system were investigated. The MnAlGe film fabricated by low-temperature substrate heating demonstrated amorphous phase and paramagnetic property. The film of c-axis orientation associated with the Cu2Sb-type structure was obtained by sputtering at a substrate heating temperature of 270°C and it exhibited perpendicular magnetic anisotropy. From the magnetization curves measured at room temperature, the uniaxial magnetic anisotropy energy, Ku, was evaluated to be in the order of 106 erg/cm3, which is consistent with the literature, although the heating processing and temperature are slightly different. Microstructural observation indicated that the c-axis oriented grains were isolated in the matrix of the amorphous phase. The film lost the c-axis orientation at elevated substrate heating temperature, resulting in loss of the anisotropic magnetic property.

DOI： 10.2320/matertrans.MT-M2020309

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Metals and Materials  

© 2020 The Japan Institute of Metals and Materials. Combined accelerating effects of ¾¸ phase transformation by in-magnetic-field annealing and Zn-addition were investigated for Mn53Zn2Al45 in magnetic fields up to 15 T. The in-field annealing for Zn-added sample accelerated the ¾¸ transformation 16 times faster than Mn55Al45 at annealing temperature of 623 K. The reduction of magnetization after finishing ¾¸ transformation was also more rapid than that of Mn55Al45. However, magnetic-field-induced acceleration of ¾¸ phase transformation and suppression of precipitation of ¢-phase were observed for Zn-added alloy Mn53Zn2Al45 annealed at 573 K. The obtained results suggested that the ¢-phase stabilized against both ¸- and ¾-phases by Zn-addition. Therefore, although the ¾¸ transformation was efficiently accelerated by in-field annealing of Mn53Zn2Al45, more precisely control of annealing time is required for obtaining high fraction of ferromagnetic ¸-phase.

DOI： 10.2320/matertrans.MT-M2020235

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© 2020 Elsevier B.V. Phase stability of hcp-Mn-Al (ε-phase) was found to improve by carbon addition. MnxAl100-xCy (50 ≤ x ≤ 63 and 0 ≤ y ≤ 2) samples were prepared by reactive sintering method. The annealing and quenching of the samples were carried out for 700 to 1100°C. The precipitation of ε-phase was observed at y = 2 even the annealing temperature of 800°C, which was β + γ2 region in the Al–Mn phase diagram. It is suggested that the carbon addition enhanced the phase stability of ε-phase and contributed for the stable synthesis of τ-phase by ε−τ transformation.

DOI： 10.1016/j.physb.2020.412379

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© 2020 Elsevier B.V. Nitridation of Sm2Fe17 powder was performed under a 5-T magnetic field for the temperature range 623–743 K to clarify the magnetic field effect on nitridation. Applying a magnetic field of 5 T promoted nitridation by approximately 0.6 nitrogen atoms per formula unit compared with zero-field nitrogenation, and almost fully-nitride Sm2Fe17N2.9 was obtained at 743 K. The magnetic field effect was discussed using a grain growth model based on magnetic properties of nitride-poor Sm2Fe17Nx (x < 3) phase and fully-nitride Sm2Fe17N3 phase. The obtained results show that in-field nitridation helps to synthesize nitride Sm2Fe17N3 system in the present condition.

DOI： 10.1016/j.jallcom.2020.155193

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© 2019 Elsevier B.V. X-ray powder diffraction, differential scanning calorimetry, and magnetization measurements were performed to investigate the effects of heat treatment on the magnetic and structural properties of as-cast and aging treated MnCoGe. The martensitic transformation temperature of the as-cast sample was 526 K for its first heating cycle, which decreased with repeating thermal cycles of 300–1273 K. MnCoGe prepared by aging treatment of 873 K for 7 days showed a first-order magnetic transition, which was accompanied by a martensitic transformation at 307 K. However, the transformation was not detected when the aging temperature was increased up to 973 K. The martensitic transformation temperature and volume of the parent phase was found to have a positive correlation.

DOI： 10.1016/j.jmmm.2019.166199

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© 2020 ISIJ. The effect of magnetic fields on solid-liquid reactions in the Fe-Ga binary system was investigated using Fe/Ga diffusion couples. The reaction and phase growth proceeded by diffusion-controlled process for both 0 and 10 T. It is found that the growth of the intermetallic phases was suppressed by magnetic fields of 10 T regardless of whether α-Fe was in a ferromagnetic or paramagnetic state. The pre-exponential factors in the parabolic coefficient of the Fe3Ga + eutectic region at 0 and 10 T were 2.50 ×104 m2/s and 1.32 ×103 m2/s, respectively. Meanwhile, activation energies at 0 and 10 T were 336 kJ/mol and 318 kJ/mol, respectively, which indicated the ineffectiveness of magnetic fields. That is, reduction of pre-exponential factor of the parabolic coefficient leads the magnetic-field-induced suppression of the reaction in Fe/Ga.

DOI： 10.2355/isijinternational.ISIJINT-2019-470

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© 2020 The Japan Institute of Metals and Materials Nitrogenation of Sm2Fe17 powder was performed under a zero field and a magnetic field of 5 T at 623, 673 and 743 K to clarify the magnetic field effect on nitrogenation. Applying a magnetic field of 5 T induced nitrogenation compared with zero-field nitrogenation, and almost fully nitride Sm2Fe17N2.9 was obtained at 743 K. Mössbauer spectroscopy results suggested that a 5-T magnetic field promoted the phase transformation to the fully-nitride Sm2Fe17N3 phase. The magnetic field effect was discussed based on the magnetic energy gain and magnetic properties of host Sm2Fe17 and fully nitride Sm2Fe17N3

DOI： 10.2320/matertrans.MT-MN2019012

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© 2020 The Japan Institute of Metals and Materials The spin reorientation and Curie temperature of Mn21xFexSb11ySny (0 ¯ x, y ¯ 0.15) compound were investigated by magnetization measurements. Spin reorientation temperature increased from 255 K at x = 0 to 383 K at x = 0.15, whereas it almost unchanged by Sn substitution. Curie temperature decreased down to 518 K with both Fe and Sn substitution. Substitution of Fe stabilized the ferrimagnetic state with magnetic moment lying in c-plane. Substitution of Sn induced the antiferromagnetic phase at low temperature. It was found that the magnetic hysteresis derived from quasi first-order magnetic phase transition exhibited at x 2 0.10 or T 2 300 K.

DOI： 10.2320/matertrans.MT-MN2019016

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© 2020 The Japan Institute of Metals and Materials Pressure effects on magnetic susceptibility» and energy gap Eg0 of narrow-gap semiconductor FeSb2 were investigated for the temperature range of 50300 K and pressures up to 13 kbar. The estimated Eg0 for ambient pressure, Eg0(0), was 29 meV. By application of pressure,» was suppressed, and Eg0(P) was estimated to be 52 meV for 13 kbar. The fourth-order expansion coefficient £ of the free energy in magnetization was positive and enhanced by applying pressures.

DOI： 10.2320/matertrans.MT-MN2019015

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© 2020 The Japan Institute of Metals and Materials The magnetization measurements were carried out for polycrystalline Au4V in magnetic fields up to 130 kOe. The spontaneous magnetic moment ps was determined to be 0.255 ®B/V at 4 K by high field magnetization. The magnetization process was analyzed on the basis of Takahashi’s spin fluctuation theory for weak itinerant electron ferromagnets. The characteristic parameters of the spin fluctuation were estimated to be TA = 1.3 © 103 K and T0 = 2.3 © 103 K using the data for 110130 kOe.

DOI： 10.2320/matertrans.MT-MN2019011

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© 2020 The Japan Institute of Metals and Materials. First-principles calculations were performed to investigate the effect of Fe substitution on the structural transformation of (Mn,Fe)CoGe and Mn(Co,Fe)Ge. The activation energy (barrier) between orthorhombic and hexagonal structures was estimated from the total energy of each of several virtual structures between them. Fe substitution reduces the activation energy, and movements of both of Co and Mn are closely related to the reduction. Moreover, the calculation result for the Fe substitution at the sites of both Mn and Co indicates that Fe atoms randomly occupy Mn and Co sites.

DOI： 10.2320/matertrans.MT-MN2019013

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Language：Japanese   Publisher：The Japan Institute of Metals and Materials  

DOI： 10.2320/materia.59.422

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© 2019 Elsevier B.V. Substitution effects on weak itinerant electron ferromagnetism in Cr-based ternary alloy CrAlGe were investigated. It was found that substitution of Cr by 3d transition metal with more electrons than Cr enhanced the spontaneous magnetization and Curie temperature. In addition, the itinerancy of CrAlGe was suppressed with the increase of electrons. The ferromagnetism of CrAlGe was related to electron number rather than lattice parameters. The origin of change of itinerancy was suggested to be Coulomb force caused by effective nuclear charge.

DOI： 10.1016/j.jmmm.2019.165677

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© 1965-2012 IEEE. In-magnetic-field annealing (IFA) effects on Zn-modified Mn-Al and Mn-Al-C were investigated at the annealing temperature of 573 K, which was around their $_Rftxt-{\mathrm {C } }$. Mn53Zn2Al45 showed the magnetic-field-induced acceleration of the phase transformation to $\text{L}1-{0}$ -phase ( $\tau $ -phase) and the suppression of that to nonferromagnetic equilibrium phase. For Mn55Al45C2, IFA effects were not clearly detected. These different magnetic field effects were discussed by the difference of the mechanism in stabilization of $\tau $ -phase. It is found by a thermal analysis that the modification of Zn stabilized $\tau $ -phase against $\epsilon $ -phase, realizing acceleration of transformation to $\tau $ -phase. The addition of carbon stabilized $\epsilon $ -phase against $\tau $ -phase. The ineffectiveness of in-field annealing for Mn-Al-C is due to the stabilization of $\epsilon $ -phase and the reduction of the Curie temperature. The combination of Zn modification and IFA is realized to synthesize high fraction of $\tau $ -phase for short annealing time and low annealing temperature.

DOI： 10.1109/TMAG.2018.2860559

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© 1965-2012 IEEE. An in-field annealing-quenching furnace utilized for magnets with a 52 mm experimental bore was developed. The cooling rate from 663 to 473 K was 38 K/s under a magnetic field of 19 T. The phase boundary between the ferromagnetic MnBi and the paramagnetic Mn1.08Bi was examined using this furnace. The phase boundary was confirmed around 663 K. It was found that the MnBi grain became elongated during recrystallization under 19 T.

DOI： 10.1109/TMAG.2018.2872105

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©2019 The Physical Society of Japan First-principles total-energy calculations showed that the stable structure of (MnxCr1−x)AlGe changes from Cu2Sb to TiSi2 structures at xc, where 0.25 > xc > 0.125. In the Cu2Sb-type structure, a ferromagnetic state occurs, that is, the magnetic moments on Mn and Cr are parallel to each other. In the TiSi2-type structure, a ferrimagnetic (ferromagnetic) state occurs with Mn (Cr) rich concentration. However, the magnetic moment per formula unit increases linearly as the concentration of Mn decreases. TiSi2-type (Mn,Cr)AlGe holds half metallicity, except in the case of MnAlGe. The whole magnetic and electronic properties of (Mn,Cr)AlGe are not sensitive to the chemical disorder between Mn and Cr atoms.

DOI： 10.7566/JPSJ.88.064709

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©2019 The Japan Institute of Metals and Materials In-field heat treatments of an Mn-Ga diffusion couple were performed at 773 K for 12, 24 and 48 h to investigate the phase formation under magnetic fields. Formation of the MnGa3, Mn2Ga5, MnGa, Mn3Ga2 and ¢-Mn phases was confirmed for magnetic fields of 0 T and 5 T. For a diffusion-controlled process, there is a parabolic relationship between the thickness of the phase layers and annealing time for the MnGa and Mn2Ga5 phases. The parabolic coefficients of MnGa and Mn2Ga5 for a zero magnetic field were determined as 8.7 © 10-3 µm2s-1 and 4.6 © 10-1 µm2s-1 respectively. For a magnetic field of 5 T, the parabolic coefficients were evaluated as 11 © 10-3 µm2s-1 for the MnGa phase and 4.5 © 10-1 µm2s-1 for the Mn2Ga5 phase.

DOI： 10.2320/matertrans.MT-MAW2019013

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© 2019 The Japan Institute of Metals and Materials. An in-field heat treatment furnace utilized for a magnet with a 50 mm room-temperature bore was made to study magnetic field effect on gas-solid reaction. Using this furnace, nitridation of Sm2Fe17 powder was performed under a 5-T magnetic field and a 0.1-MPa nitrogen gas pressure for the temperature range 623 to 743 K. Applying a magnetic field of 5 T promoted nitridation by approximately 0.6 nitrogen atoms per formula unit compared with zero-field nitridation, and almost fully nitride Sm2Fe17N2.9 was obtained at 743 K.

DOI： 10.2320/matertrans.MT-MAW2019009

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Language：Japanese   Publisher：The Japan Institute of Metals and Materials  

<p>The magnetic field effect on phase formations of ferromagnetic Mn-Al (τ-phase) was evaluated. The transformation from ε-phase with hcp-structure to τ-phase was accelerated by annealing in magnetic field. With in-field annealing at 623 K, the magnetization of the sample annealed at 15 T was a maximum of 72.2 A･m²/kg at 1.5 T, which was over 4 times larger than that annealed in a zero field. Meanwhile, the precipitation of non-ferromagnetic β-phase was suppressed by in-field annealing. Magnetic field-induced acceleration of ε-τ transformation and suppression of τ-β transformation were due to the gain of Zeeman energy of τ-phase.</p>

DOI： 10.2320/jinstmet.J2018057

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J-GLOBAL

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

© 2010-2012 IEEE. The magnetic properties of ferrimagnetic Mn1.9Fe0.1Sb0.9Sn0.1 with a Cu 2Sb-type tetragonal structure were investigated in the temperature range 10 to 360 K and in magnetic fields up to 5 T. The lattice parameters a and c were estimated to be 0.407 and 0.655 nm, respectively, at 293 K. The saturation magnetization at 10 K was 39.1 A m2/kg (1.62 μB per formula unit), which was slightly smaller than the value at 75 K, and the magnetization showed thermal hysteresis between 70 and 230 K. The compound showed a first-order magnetic transition from the ferrimagnetic to a paramagnetic-like state with a thermal hysteresis in the vicinity of 320 K. The results are discussed on the basis of the ferrimagnetic and antiferromagnetic transitions and spin reorientation.

DOI： 10.1109/LMAG.2017.2768023

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© 2018 Author(s). Cu-substitution effects on ferromagnetism in Cr-base ternary alloy CrAlGe with an orthorhombic TiSi2-type structure was investigated. The lattice parameters of Cr0.95Cu0.05AlGe were a = 4.748 Å, b = 8.209 Å and c = 8.696 Å at room temperature. The spontaneous and effective moment were determined to be ps = 0.533 μB/f.u at 5 K and peff = 1.89 μB/f.u, respectively. The Curie temperature TC was estimated to be 108 K. These ps and TC of Cr0.95Cu0.05AlGe were larger than those of CrAlGe and Ti-substituted compound. The peff/ps was determined to be 3.55, which was smaller than that of CrAlGe and Ti-substituted compound. Obtained results suggest that the substitution of Cu for Cr in CrAlGe leads suppression of its weak itinerant electron ferromagnetism.

DOI： 10.1063/1.5043105

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© 2018 Author(s). The magnetic properties of Mn1-xTMxAlGe (TM = V, Fe and Cu) were investigated for x ≤ 0.2. The spontaneous magnetization decreased with increasing x. A remarkable decrease in the Curie temperature TC was observed for TM = Fe. For ferromagnetic MnAlGe (x = 0) and TM = nonmagnetic Cu (x = 0.2), Curie-Weiss law was confirmed. The compounds with TM = V and Fe (x = 0.2) did not show Curie-Weiss law, and the data of reciprocal susceptibility vs. temperature bent, indicating change of the magnetism from ferromagnetism. Obtained results suggested that the magnetic moments of V and Fe were aligned antiparallel to those of Mn, resulting in the ferrimagnetism-like behavior.

DOI： 10.1063/1.5043069

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© 2018 Author(s). First-principles calculations for the ferromagnetic systems (Co,Fe)MnGe and Co(Mn,Fe)Ge show the hexagonal cell volume decreases as an amount of Fe increases mainly because of the reduction of the lattice constant c. The Fe substitution produces a reduction in the distance between adjacent atoms along the direction of the c axis and an increase in charge density between those atoms. This enhancement of the covalent bond is responsible for the hexagonal-structure stabilization or a decrease of the structural transition temperature from hexagonal to orthorhombic phases.

DOI： 10.1063/1.5042834

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© 2018 Elsevier B.V. The magnetic phase transitions and their thermal transformation arrest (TTA) behavior of Cr-substituted Mn2Sb were investigated. Mn1.92Cr0.08Sb showed the first-order magnetic transition between antiferromagnetic (AFM) and ferrimagnetic (FRI) state. The TTA phenomenon was observed in field-cooling process under magnetic field of μ0H ≥ 4 T. The relaxation process from the arrested FRI to AFM state was explained by stretched exponential function. As decreasing temperature, the magnetic relaxation changed from Arrhenius-type to non-Arrhenius ones. The characteristic relaxation time was evaluated to be the order of 105 ∼ 106 s, which indicated indeed arresting of the magnetic transition. During the process, the decrease in the magnetization due to the relaxation changed into an increase with the thermal fluctuation of ∼1%. These relaxation behaviors are explained by the density and the frequency of the reversal of triple-layered magnetic moments.

DOI： 10.1016/j.jmmm.2018.04.038

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© 2018 Elsevier B.V. The magnetic and structural properties of Mn1−xCrxAlGe (0 ≤ x ≤ 1.0) compounds were investigated. The spontaneous magnetization Ms and Curie temperature TC of Mn1−xCrxAlGe has a cusp at x = 0.2. The maximum values of Ms and TC are 1.74 μB/f.u. and 601 K, respectively. It was found that the tetragonal Cu2Sb-type structure was stable for 0 ≤ x ≤ 0.75, whereas orthorhombic TiSi2-type structure was observed for x ≥ 0.8. The reciprocal susceptibility as a function of temperature suggested that the magnetic moment of Cr is antiferromagnetically coupled with that of Mn in Cu2Sb-type structure.

DOI： 10.1016/j.jmmm.2018.02.022

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© 2018 Elsevier B.V. The magnetic field effect on the reactive sintering process of MnBi was investigated. Magnetic-field-induced enhancement of the reaction was found to be exhibited at the initial stages. The coercivity field decreased with an increase in the in-field annealing time. The kinetics of the reaction were in good agreement with the diffusion-controlled reaction model. It is suggested that the decrease in activation energy at the initial stages of reaction increased the amount of formed MnBi phases, resulting in enhancement of the reaction Mn + Bi to MnBi phase by in-field reactive sintering.

DOI： 10.1016/j.jmmm.2018.01.026

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© 2018 The Physical Society of Japan. The Pressure effect on the magnetic properties of the weak itinerant electron ferromagnet CrAlGe was investigated at pressures up to 1.0 GPa. The spontaneous magnetic moment ps and Curie temperature TC decreased with increasing applied pressure P. The pressure derivatives of ps and TC were dps=dP = -3.98 × 10-5 μB=MPa and dTC=dP = -6.58 × 10-3K=MPa, respectively. These obtained results are discussed on the basis of Takahashi's spin fluctuation theory for weak itinerant electron ferromagnets. The characteristic parameters T0 and TA increased with pressure.

DOI： 10.7566/JPSJ.87.014701

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© 2018 The Japan Institute of Metals and Materials. The magnetic and structural properties of ferrimagnetic (FRI) Mn1.9Fe0.1Sb0.9Sn0.1 with a Cu2Sb-type tetragonal structure were studied by magnetization and high field X-ray diffraction (XRD) measurements in 10 ≤ T ≤ 773 K and in magnetic fields μ0H up to 5 T. The lattice parameters a and c at 285 K were estimated to be 0.407 nm and 0.655 nm, respectively. The saturation magnetization at 10 K was determined to be 39.1 Am2/kg. It was observed that a first order magnetic transition (FOMT) with a thermal hysteresis occurred in the vicinity of 310 K under low magnetic fields. This FOMT disappeared easily by applying magnetic fields over 0.4 T.

DOI： 10.2320/matertrans.M2017291

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© 2018 Japan Institute of Metals (JIM). All rights reserved. The magnetic and structural properties of MnCo0.92Fe0.08Ge1-xSnx (x = 0.02, 0.05, and 0.1) were investigated. A first-order magnetic transition was observed, which was accompanied by the martensitic transformation from a hexagonal Ni2In-Type to an orthorhombic TiNiSi-Type structure in the vicinity of 320K for x = 0.02 and 170K for x = 0.05 with thermal hysteresis of approximately 20 K. The magnetization of MnCo0.92Fe0.08Ge0.95Sn0.05 was estimated to be 102Am2 kg-1 in 5 T at 10 K. High field magnetization curves up to 55 T for MnCo0.92Fe0.08Ge0.95Sn0.05indicated the field-induced martensitic transformation. Mössbauer spectroscopy experiments revealed that Fe atoms occupied 79%85% in the Co-site and 21%15% in the Mn-site.

DOI： 10.2320/matertrans.M2018183

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© 2017 by the authors. Licensee MDPI, Basel, Switzerland. The transformation behaviors on metamagnetic shape memory Ni46.4Mn38.8In12.8Co2.0 film were investigated by X-ray diffraction experiments in the temperature up to 473 K and magnetic fields μ0H up to 5 T. The prepared film showed the parent phase with L21 structure at 473 K, and with preferred orientation along the 111 plane. The magnetic field induced reverse transformation was directly observed at T = 366 K, which was just around the reverse transformation starting temperature.

DOI： 10.3390/met7090364

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© Published under licence by IOP Publishing Ltd. Magnetic properties for CrAlGe with an orthorhombic TiSi2-type structure were investigated under ambient pressure and hydrostatic pressure. CrAlGe is ferromagnetic at the temperature below Curie temperature T C of 80 K and has the spontaneous magnetic moment p s of 0.41 μ B/f.u. at 5 K and the effective moment p eff of 1.89 μ B/f.u. under ambient pressure. For the temperature T below 30 K, the decrease in p s(T) 2/p s(5K)2 was proportional to T 2. However, the decrease in p s(T) 2/p s(5K)2 was proportional to T 4/3 for 30 K < T < T C. The ratio p eff/p s was consistent with the theoretical curve of the generalized Rhodes-Wohlfarth plot (Takahashi plot). Obtained results suggest that CrAlGe is a weak itinerant electron ferromagnet. By applying a high pressure of 1 GPa, T C decreased by approximately 10 K.

DOI： 10.1088/1742-6596/868/1/012018

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

© 2010-2012 IEEE. Magnetic and structural properties of Sn-substituted Mn2Sb were investigated. A first-order magnetic transition (FOMT) from a ferrimagnetic (FRI) to an antiferromagnetic state occurred between 100 and 200 K, which was accompanied by an iso-structural transformation. Upon cooling in 5 T, the residual FRI phase was observed even at 10 K, and the residual FRI phase slightly decreased with increasing time. The results indicate that the FOMT of Mn2Sb0.9Sn0.1 is arrested by applying a magnetic field.

DOI： 10.1109/LMAG.2016.2628350

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©2017 The Japan Institute of Metals and Materials. Microstructural analysis was performed for Mn-Bi prepared by in-field solid-phase reactive sintering, in order to investigate the origin of magnetic field effects on the reaction. The number of formed MnBi phase around Mn grain in 10 T was almost 3 times larger than that in a zero field. The results indicated that the magnetic field enhanced the phase formation rate of MnBi phase. Due to the enhancement of the phase formation rate, the fraction of MnBi phase was drastically increased by in-field annealing.

DOI： 10.2320/matertrans.MBW201609

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN INST METALS  

© 2017 The Japan Institute of Metals and Materials. The phase formation of ferromagnetic L10-MnAl (τ-phase) was accelerated by annealing in magnetic field. With in-field annealing at 623 K, the magnetization of the τ-phase annealed at 15 T was a maximum of 72.2 A･m2/kg at 1.5 T, which is over 4 times larger than that annealed without an external magnetic field for the same annealing time. On the other hand, the transformation from τ-phase to β-phase was suppressed under magnetic field. The obtained bulk sample did not show magnetic anisotropy because of the ε-τ solid-state transformation. Obtained results suggested that magnetic field induced acceleration of transformation was due to the gain of Zeeman energy which increases the driving force of the ε-τ transformation.

DOI： 10.2320/matertrans.MAW201709

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Metals and Materials  

DOI： doi:10.2320/matertrans.M2015382

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Elevier  

DOI： doi:10.1016/j.phpro.2015.12.148

Other Link： http://www.sciencedirect.com/science/article/pii/S1875389215017873

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DOI： doi:10.1016/j.phpro.2015.12.126

Other Link： http://www.sciencedirect.com/science/article/pii/S1875389215017654

Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Elsevier  

DOI： 10.1016/j.jmmm.2015.07.114

Other Link： http://www.sciencedirect.com/science/article/pii/S0304885315304212

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Language：English   Publishing type：Research paper (scientific journal)  

Publisher：公益社団法人 日本金属学会  

DOI： 10.2320/materia.60.40

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

Publisher：The Japan Institute of Metals and Materials  

DOI： 10.2320/materia.59.5

Publisher：公益社団法人 日本金属学会  

DOI： 10.2320/materia.59.50

Language：Japanese   Publisher：公益社団法人 日本金属学会  

DOI： 10.2320/materia.59.212

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