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K R Priolkar - One of the best experts on this subject based on the ideXlab platform.
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Importance of site occupancy and absence of strain Glassy Phase in Ni$_{2-x}$Fe$_{x}$Mn$_{1.5}$In$_{0.5}$
Journal of Alloys and Compounds, 2019Co-Authors: R Nevgi, Mehmet Acet, K R PriolkarAbstract:Martensitic transition temperature steadily decreases in Ni$_{2-x}$Fe$_{x}$Mn$_{1.5}$In$_{0.5}$ and is completely suppressed at $x$ = 0.2. Despite suppression of martensitic transition, Ni$_{1.8}$Fe$_{0.2}$Mn$_{1.5}$In$_{0.5}$ does not display the expected strain Glassy Phase. Instead, a ground state with dominant ferromagnetic interactions is observed. A study of structural and magnetic properties of $x$ = 0.2 reveal that the alloy consists of a major Fe rich cubic Phase and a minor Fe deficient monoclinic Phase favoring a ferromagnetic ground state. This is exactly opposite of that observed in Ni$_2$Mn$_{1-y}$Fe$_{y}$In$_{0.5}$ wherein a strain Glassy Phase is observed for $y$ = 0.1. The change in site symmetry of Fe when doped for Ni in contrast to Mn in the Heusler composition seems to support the growth of the ferromagnetic Phase.
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unusual strain Glassy Phase in fe doped ni2mn1 5in0 5
Applied Physics Letters, 2018Co-Authors: R Nevgi, K R PriolkarAbstract:Fe doped Ni2Mn1.5In0.5, particularly, Ni2Mn1.4Fe0.1In0.5, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss which obeys the Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both frequency dependence and ergodicity breaking are characteristics of a strain Glassy Phase and occur due to the presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non-interacting with other strain domains due to the presence of Fe impurities.Fe doped Ni2Mn1.5In0.5, particularly, Ni2Mn1.4Fe0.1In0.5, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss which obeys the Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both frequency dependence and ergodicity breaking are characteristics of a strain Glassy Phase and occur due to the presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non-interacting with other strain domains due to the presence of Fe impurities.
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Unusual Strain Glassy Phase in Fe doped Ni$_2$Mn$_{1.5}$In$_{0.5}$
arXiv: Materials Science, 2018Co-Authors: R Nevgi, K R PriolkarAbstract:Fe doped Ni$_2$Mn$_{1.5}$In$_{0.5}$, particularly, Ni$_2$Mn$_{1.4}$Fe$_{0.1}$In$_{0.5}$, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss that obeys Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both, frequency dependence and ergodicity breaking are characteristics of a strain Glassy Phase and occur due to presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non interacting with other strain domains due to presence of Fe impurity.
R Nevgi - One of the best experts on this subject based on the ideXlab platform.
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Importance of site occupancy and absence of strain Glassy Phase in Ni$_{2-x}$Fe$_{x}$Mn$_{1.5}$In$_{0.5}$
Journal of Alloys and Compounds, 2019Co-Authors: R Nevgi, Mehmet Acet, K R PriolkarAbstract:Martensitic transition temperature steadily decreases in Ni$_{2-x}$Fe$_{x}$Mn$_{1.5}$In$_{0.5}$ and is completely suppressed at $x$ = 0.2. Despite suppression of martensitic transition, Ni$_{1.8}$Fe$_{0.2}$Mn$_{1.5}$In$_{0.5}$ does not display the expected strain Glassy Phase. Instead, a ground state with dominant ferromagnetic interactions is observed. A study of structural and magnetic properties of $x$ = 0.2 reveal that the alloy consists of a major Fe rich cubic Phase and a minor Fe deficient monoclinic Phase favoring a ferromagnetic ground state. This is exactly opposite of that observed in Ni$_2$Mn$_{1-y}$Fe$_{y}$In$_{0.5}$ wherein a strain Glassy Phase is observed for $y$ = 0.1. The change in site symmetry of Fe when doped for Ni in contrast to Mn in the Heusler composition seems to support the growth of the ferromagnetic Phase.
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unusual strain Glassy Phase in fe doped ni2mn1 5in0 5
Applied Physics Letters, 2018Co-Authors: R Nevgi, K R PriolkarAbstract:Fe doped Ni2Mn1.5In0.5, particularly, Ni2Mn1.4Fe0.1In0.5, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss which obeys the Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both frequency dependence and ergodicity breaking are characteristics of a strain Glassy Phase and occur due to the presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non-interacting with other strain domains due to the presence of Fe impurities.Fe doped Ni2Mn1.5In0.5, particularly, Ni2Mn1.4Fe0.1In0.5, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss which obeys the Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both frequency dependence and ergodicity breaking are characteristics of a strain Glassy Phase and occur due to the presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non-interacting with other strain domains due to the presence of Fe impurities.
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Unusual Strain Glassy Phase in Fe doped Ni$_2$Mn$_{1.5}$In$_{0.5}$
arXiv: Materials Science, 2018Co-Authors: R Nevgi, K R PriolkarAbstract:Fe doped Ni$_2$Mn$_{1.5}$In$_{0.5}$, particularly, Ni$_2$Mn$_{1.4}$Fe$_{0.1}$In$_{0.5}$, despite having an incommensurate, modulated 7M martensitic structure at room temperature exhibits frequency dependent behavior of storage modulus and loss that obeys Vogel-Fulcher law as well as shows ergodicity breaking between zero field cooled and field cooled strain measurements just above the transition temperature. Both, frequency dependence and ergodicity breaking are characteristics of a strain Glassy Phase and occur due to presence of strain domains which are large enough to present signatures of long range martensitic order in diffraction but are non interacting with other strain domains due to presence of Fe impurity.
Akihisa Inoue - One of the best experts on this subject based on the ideXlab platform.
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clustered crystalline structures as Glassy Phase approximants
Intermetallics, 2009Co-Authors: Dmitri V Louzguineluzgin, A R Yavari, G Vaughan, Akihisa InoueAbstract:This paper presents some crystalline structures which can be taken as the approximants of the corresponding metallic Glassy Phases. Such Phases have a clustered structure and preferably (but not strictly necessarily) a large unit cell. Peak intensities of their radial distribution functions (RDFs) must be integrated at a step of about 0.01 nm in order to obtain RDFs similar to those of the corresponding Glassy alloys owing to a degree of disorder related to the corresponding Glassy structures.
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comparative study on Glassy Phase stabilities of zr co al and zr ni al metallic glasses
Materials Transactions, 2005Co-Authors: Masashi Hasegawa, Tsuyoshi Taketomi, Hidemi Kato, Tsunehiro Takeuchi, Uichirou Mizutani, Akihisa InoueAbstract:The Phase stabilities ofZr-Co-Al and Zr-Ni-Al metallic glasses have been investigated by the thermal analysis and compared with each other. It is found that the largest ΔT x , T g /T l and y parameters of the former are larger than those of the latter, indicating that the former have higher Glassy Phase stability than the latter. It is also found that the optimum compositions of the former are Zr-poorer and Al-richer than those of the latter and that their transition metal compositions are almost the same. Since Co and Ni have almost the same atomic radius and mixing enthalpy against Zr which are factors correlated with the Glassy Phase stability, this composition difference may be attributable to another factor, i.e. their difference of the electronic contribution due to the different electronic structure around the Fermi level.
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mechanically induced crystalline Glassy Phase transformations of mechanically alloyed ta55zr10al10ni10cu15 multicomponent alloy powders
Journal of Alloys and Compounds, 2003Co-Authors: Sherif M Eleskandarany, Wei Zhang, Akihisa InoueAbstract:Abstract New multicomponent Ta-based Glassy alloy powder was synthesized by mechanical alloying (MA) the elemental powders of Ta 55 Zr 10 Ni 10 Al 10 Cu 15 at room temperature, using a low-energy ball milling technique. During the early stage of milling the agglomerated crystalline powders are mechanically crushed and fresh surfaces are rapidly created. Kneading of such ground powders enhances the atomic diffusion and leads to local alloying. As the MA time increases, the number of vacancies in the Ta lattice (base material) increases so that the atoms of the alloying elements for Zr, Al, Ni and Cu tend to migrate to the open defected lattice of metallic Ta. The number of atoms of the alloying elements that migrate to the bcc lattice of the base material are increasing with increasing MA time and this leads to a monotonic expansion of the Ta lattice. Further milling time (86–130 ks) plays an important role in increasing the rate of diffusion and this leads to an increase in the number of migrated atoms of the alloying elements that pass into the Ta lattice. The a 0 of the yielded solid solution at this stage does not change anymore with increasing MA time and a homogeneous supersaturated bcc-solid solution is obtained after 130 ks of MA time. This solid solution, which is subjected to continuous imperfections, is gradually transformed into a Glassy Phase upon increasing the MA time. The Glassy powders of the final-product (1080 ks) in which its glass transition temperature ( T g ) lies at a high temperature (834 K), crystallize through a single sharp exothermic peak at 1004 K ( T x ). The total enthalpy change of crystallization (Δ H x ) is −10.32 kJ/mol. The width of the supercooled liquid region before crystallization (Δ T x ) of the synthesized Glassy powder shows the largest value (170 K) of any reported metallic Glassy system.
M M Koza - One of the best experts on this subject based on the ideXlab platform.
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static and dynamic structure factor in solid 4he absence of a Glassy Phase
EPL, 2013Co-Authors: Y Mukharsky, A Braslau, Jacques Bossy, T Hansen, M M KozaAbstract:We present results on neutron scattering in solid 4He in the range of parameters where supersolidity is observed. The measurements address, among other questions, the viability of one possible mechanism of supersolidity: via a metastable amorphous Phase. We have attempted to observe a Glassy Phase by neutron scattering. We have found that it is impossible to do this by total scattering, as it would be common in a classical solid, due to an extremely large inelastic diffuse signal related to the anomalously strong zero-point motion of helium atoms. This raises a general question on the interpretation of such scattering as the signature of an amorphous Phase. Results from energy-resolved elastic scattering are heavily influenced by multiple scattering of neutrons which may be the major contribution to the measured elastic signal, but allow to put the limit on the concentration of an amorphous Phase to ?5% in a polycrystal with millimeter-size crystallites and to ?2% in a single crystal. The values of NCRIf, expected from these limits should be much lower, although exact values depend strongly on a particular model of glass-related supersolidity.
V. A. Tikhii - One of the best experts on this subject based on the ideXlab platform.
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Formation of a disordered (Glassy) Phase in deformed solid 4He in the region of supersolid state
Journal of Experimental and Theoretical Physics, 2010Co-Authors: I. A. Degtyarev, A. A. Lisunov, V. A. Maidanov, V. Yu. Rubanskiy, S. P. Rubets, E. Ya. Rudavskii, A. S. Rybalko, V. A. TikhiiAbstract:A method has been proposed to create disorder in helium crystals by their deformation immediately during the experiment. Precise measurements of the pressure have been performed at a constant volume in samples of various qualities. It has been revealed that excess pressure, which is characterized by the quadratic temperature dependence typical of the disordered Glassy Phase and of the dislocation contribution to the pressure, is observed in the deformed crystals along with the phonon contribution to the pressure. The effect is observed in the supersolid-state region and disappears after the careful annealing of the crystals. The ultraslow relaxation of the pressure also characteristic of the Glassy Phase has been observed in the process of annealing of the crystals. The obtained experimental results have been analyzed in the framework of the dislocation model and the model of two-level tunneling states.
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observation of a Glassy Phase of sup 4 he in the region of supersolid effects
Physical Review B, 2007Co-Authors: V N Grigorev, V. A. Maidanov, S. P. Rubets, A. S. Rybalko, Ye. V. Syrnikov, Yu V Rubanskii, Ya E Rudavskii, V. A. TikhiiAbstract:High-precision pressure measurements in solid {sup 4}He, grown by the capillary blocking technique, have been made in temperatures range from 50 to 500 mK. The temperature dependence of pressure indicates that aside from the usual phonon contribution {approx}T {sup 4}, there is an additional contribution {approx}T {sup 2}, the latter becoming dominant at temperatures T<300 mK, where an abnormal behavior attributed to supersolidity has been observed. The data suggest the appearance of a Glassy Phase (that might be responsible for the anomalous behaviors observed previously). A dramatic pressure decrease has been observed under annealing of the samples. The Glassy contribution to the pressure can be eliminated in well-annealed crystals.
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Observation of a Glassy Phase in Solid 4He in the Supersolidity Region
arXiv: Disordered Systems and Neural Networks, 2007Co-Authors: V. N. Grigor’ev, V. A. Maidanov, S. P. Rubets, E. Ya. Rudavskii, A. S. Rybalko, V. Yu. Rubanskii, Ye. V. Syrnikov, V. A. TikhiiAbstract:High-precision pressure measurements in solid 4He, grown by the capillary blocking technique, have been made in temperatures range from 50 to 500 mK. The temperature dependence of pressure indicates that aside from the usual phonon contribution ~T^4, there is an additional contribution ~ T^2, the latter becoming dominant at temperatures T < 300 mK, where an abnormal behavior attributed to supersolidity has been observed. The data suggest the appearance of a Glassy Phase (that might be responsible for the anomalous behaviors observed previously).
