A5075666738- Shape Memory Alloy Transformations
- Magnetic and transport properties of perovskites and related materials
- Heusler alloys: electronic and magnetic properties
- Magnetic Properties and Applications
- Intermetallics and Advanced Alloy Properties
- Titanium Alloys Microstructure and Properties
- Creativity in Education and Neuroscience
- High Entropy Alloys Studies
- Magnetic Properties of Alloys
- Microstructure and Mechanical Properties of Steels
- Rare-earth and actinide compounds
- Metallurgical and Alloy Processes
- High-pressure geophysics and materials
- Microstructure and mechanical properties
- Multiferroics and related materials
- Bone Tissue Engineering Materials
- MXene and MAX Phase Materials
- Metallic Glasses and Amorphous Alloys
- Advanced Welding Techniques Analysis
- High Temperature Alloys and Creep
- Metal and Thin Film Mechanics
- Advanced Thermoelectric Materials and Devices
- Semiconductor materials and interfaces
- Metallurgy and Material Forming
- Solidification and crystal growth phenomena
Tohoku University
2016-2025
The University of Tokyo
2022
Shanghai University
2016
RIKEN Center for Emergent Matter Science
2016
Nippon Soken (Japan)
2016
RIKEN
2016
Institute of Metallurgy
2013-2014
Georgia Institute of Technology
2001-2004
Kyoto University Research Reactor Institute
1999
A superelastic alloy formed from common elements operates over a wide temperature window.
To clarify the electronic, lattice, and magnetic contribution to inverse magnetocaloric effect (IMCE) in metamagnetic shape-memory alloy ${\mathrm{Ni}}_{45}{\mathrm{Co}}_{5}{\mathrm{Mn}}_{50\ensuremath{-}x}{\mathrm{In}}_{x}$, magnetization, effect, specific-heat measurements were carried out a wide range of fields temperatures. The IMCEs ${\mathrm{Ni}}_{45}{\mathrm{Co}}_{5}{\mathrm{Mn}}_{36.7}{\mathrm{In}}_{13.3}$ directly measured as adiabatic temperature changes pulsed up 15 T. A maximum...
Temperature-stable superelasticity Shape memory alloys are superelastic, which means that they can recover their original shape after a large amount of strain. However, in most alloys, this behavior tends to only work well for small range temperatures. Xia et al. identified an iron-manganese-aluminum-chromium-nickel alloy is virtually temperature independent (see the Perspective by La Roca and Sade). This distinctive property attractive variety applications variations normal, such as space...
The elastocaloric effect in a columnar-grained Cu71.5Al17.5Mn11 shape memory alloy fabricated by directional solidification was investigated. A large entropy change of 25.0 J/kg K generated the reversible martensitic transformation demonstrated. adiabatic temperature 12-13 directly measured, covering wide range more than 100 K. low applied stress with specific ability 100.8 K/GPa identified and potentially attainable operational window as 215 also discussed. outstanding refrigeration...
Abstract In advanced applications such as aerospace and space exploration, materials must balance lightness, functionality extreme thermal fluctuation resistance 1,2 . Shape-memory alloys show promise with strength, toughness substantial strain recovery due to superelasticity, but maintaining low mass effective operation at cryogenic temperatures is challenging 3–6 We hereby introduce a new shape-memory alloy that adheres these stringent criteria. Predominantly composed of Ti Al chemical...
The magnetic properties and magnetocaloric effect (MCE) of ternary intermetallic RE2Cu2Cd (RE = Dy Tm) compounds its composite materials have been investigated in detail. Both undergo a paramagnetic to ferromagnetic transition at own Curie temperatures TC ~ 48.5 15 K for Dy2Cu2Cd Tm2Cu2Cd, respectively, giving rise the large reversible MCE. An additionally can be observed around 16 compound. maximum values entropy change (-ΔSMmax) are estimated 17.0 20.8 J/kg field 0-70 kOe, respectively. A...
The concentration dependence of magnetic properties in the austenite phase NiCoMnIn and NiCoMnSn Heusler alloys was systematically investigated by magnetization measurements. TC for Ni(50-x)CoxMn(50-y)Sny linearly increases with increasing Co content fixed Sn content. Although showing a concave curve Ni50Mn(50-y)Sny ternary alloys, content-dependence moment per formula unit changes from to straight line when is substituted Ni. On other hand, In Ni45Co5Mn(50-y)Iny perfectly linear as that...
Normally, shape memory effect (SME) is obtained by the reverse martensitic transformation, therefore only induced heating a sample from deformed martensite phase. In this study, we report phenomenon of cooling-induced SME, observed in Co2Cr(Ga,Si) Heusler alloy, where normal heating-induced SME can be at same time. The attributed to an abnormal transformation alloy. Moreover, inverse temperature dependence superelastic stress was also observed. discoveries these phenomena provide application...
The magnetic properties and magnetocaloric effect (MCE) in RE2Cu2In (RE = Er Tm) compounds its composite materials have been investigated. A large reversible MCE is observed at around their own Curie temperature of T C ~ 39.4 31.6 K for Er2Cu2In Tm2Cu2In, respectively. Under a field change 0–7 T, the maximum values entropy () are estimated to be 18.4 18.2 J kg−1 K−1 table-like 20–50 enhanced refrigerant capacity (RC) realized Er2Cu2In–Tm2Cu2In materials. For changes 0–5 improvements RC reach...
The demand for biomaterials has been increasing along with the increase in population of elderly people worldwide. mechanical properties and high wear resistance metallic make them well-suited use as substitutes or support damaged hard tissues. However, unless these also have a low Young's modulus similar to that human bones, bone atrophy inevitably occurs. Because is typically associated poor resistance, it difficult realize simultaneously. Also, superelastic property shape-memory alloys...
Abstract Crystalline metals can have large theoretical elastic strain limits. However, a macroscopic block of conventional crystalline practically suffers very limited deformation <0.5% with linear stress–strain relationship obeying Hooke’s law. Here, we report on the experimental observation tensile an >4.3% in Cu-based single alloy at its bulk scale room temperature. The that originates from reversible lattice phase is demonstrated by situ microstructure and neutron diffraction...
Magnetic properties and martensitic transformation behaviors of NiCoMnAl metamagnetic shape memory alloys were investigated. The kinetic arrest phenomenon was observed at about 40 K during thermomagnetization measurements. At temperatures ranging from 4.2 to 200 K, magnetic field-induced reverse confirmed by a pulse magnetometer with field up 45 T. By plotting the equilibrium fields against measured temperature, entropy change calculated using Clausius-Clapeyron equation. found become zero...
The martensitic transformation behavior in a Ni45Co5Mn36In14 was investigated at low temperatures. Almost perfect superelasticity confirmed below 200 K. reverse finishing stress monotonically decreased with decreasing temperature and the forward starting changed from decrease to an increase ∼125 dependence of equilibrium had same tendency as that magnetic field, allowing thermal arrest be determined. hysteresis stress-induced also similar magnetic-field-induced transformation, levels...
The phase stabilities and ordering tendencies in the quaternary full-Heusler alloys NiCoMnAl NiCoMnGa have been investigated by situ neutron diffraction, calorimetry, magnetization measurements. was found to adopt $\mathrm{L}{2}_{1}$ structure, with distinct Mn Ga sublattices but a common Ni-Co sublattice. A second-order transition $\mathrm{B}2$ disorder also between observed at $1160\phantom{\rule{0.28em}{0ex}}\text{K}$. In contrast, slow cooling or low-temperature annealing treatments are...
We report the martensitic transformation behavior in Co-V-Ga Heusler alloys. Thermoanalysis and thermomagnetization measurements were conducted to observe transformation. By using a transmission electron microscope an situ X-ray diffractometer, was found occur from L21 parent phase D022 martensite phase. Phase diagrams determined for two pseudo-binary sections where detected. Magnetic properties, including Curie temperatures spontaneous magnetization of phase, also investigated. The magnetic...