A5026103149- Metallic Glasses and Amorphous Alloys
- Intermetallics and Advanced Alloy Properties
- Rare-earth and actinide compounds
- Glass properties and applications
- Hydrogen Storage and Materials
- Phase-change materials and chalcogenides
- Titanium Alloys Microstructure and Properties
- X-ray Spectroscopy and Fluorescence Analysis
- Aluminum Alloys Composites Properties
- Advanced X-ray Imaging Techniques
- Shape Memory Alloy Transformations
- Microstructure and mechanical properties
- Material Dynamics and Properties
- Electron and X-Ray Spectroscopy Techniques
- Advanced Welding Techniques Analysis
- Crystallography and Radiation Phenomena
- Metallurgical and Alloy Processes
- Nuclear Physics and Applications
- Hydraulic and Pneumatic Systems
- High-pressure geophysics and materials
- Nanoporous metals and alloys
- Aluminum Alloy Microstructure Properties
- Structural Behavior of Reinforced Concrete
- Advanced Materials Characterization Techniques
- Quasicrystal Structures and Properties
Utsunomiya University
2012-2024
Nippon Steel (Germany)
2016
Tohoku University
1987-2012
Ministry of Land, Infrastructure, Transport and Tourism
2011
Kyoto University
1997-2008
Washington Center
2007
University of Washington
2004-2007
Institute for Materials Research, Tohoku University
2006
University of Tsukuba
2002-2003
Aichi Institute of Technology
2002
By utilizing ultrasonic annealing at a temperature below (or near) the glass transition ${T}_{\mathrm{g}}$, we revealed microstructural pattern of partially crystallized Pd-based metallic with high-resolution electron microscopy. On basis observed microstructure, inferred plausible model fragile glasses composed strongly bonded regions surrounded by weakly (WBRs). The crystallization in WBRs such low under vibrations is caused accumulation atomic jumps associated $\ensuremath{\beta}$...
An x-ray absorption fine-structure (XAFS) spectroscopy beamline, BL01B1, was installed at a bending magnet source SPring-8 and has been open to users since October 1997.It designed for XAFS experiments covering wide energy range.Position tables automatical control programs were established adjust the optics achieve performance of beamline under each experimental condition.This enabled conventional measurements be made with good data quality from 4.5 110 keV.
Glass-transition region is still a somewhat ``dark area'' in the field of materials science. In order to shed more light on this phenomenon, glass-transition behavior was studied ${\text{Zr}}_{55}{\text{Cu}}_{30}{\text{Al}}_{10}{\text{Ni}}_{5}$ glassy alloy by monitoring its specific-heat capacity measured using differential scanning calorimeter during heating step-scan mode. This reduces influence kinetic effects which shield transition. It suggested that two types relaxation (likely...
It has been reported that the structural stability is significantly deteriorated under radio-frequency-ultrasonic perturbation at relatively low temperatures, e.g., near/below glass transition temperature T(g), even for thermally stable metallic glasses. Here, we consider an underlying mechanism of ultrasound-induced instability, i.e., crystallization, a structure to grasp nature glass-to-liquid Mechanical spectroscopy analysis indicates instability caused by atomic motions resonant with...
The tetrahedrally close-packed structure of the μ-phase Co7Mo6 has been investigated by many-beam imaging with [110] axial illumination. Twinnings, stacking faults and other defects have revealed in terms characteristic coordination polyhedrons aid multislice computations. Occurrence P-phase is found at composition 44 at%Mo. Simulated images based on models agree well observations.
The phase transition behavior of the local structure around Fe in a shape-memory-alloy-related material, ${\text{Ti}}_{50}{\text{Ni}}_{44}{\text{Fe}}_{6}$, was evaluated by x-ray fluorescence holography. $\text{Fe}\text{ }K\ensuremath{\alpha}$ holograms were recorded at 225 and 100 K, which correspond to parent commensurate phases, respectively. atomic images both phases show that first neighbor Ti atoms Fe, fluctuating phase, is strongly stabilized clusterlike with radius $8\text{...
Glass-forming ability, thermal behavior and mechanical properties of Ni80−xPdxP20 (10at%≤x≤35at%) glassy alloys have been investigated. The with Pd contents higher than 25 at% exhibit high glass-forming as is evidenced from the formation a cylindrical Ni50Pd30P20 rod diameter 21 mm. Ni-rich bulk metallic glasses show relatively strength in compression tension tests. More notably, plastic strains exceeding 2% were obtained for all at room temperature test.
We have investigated the origin of significantly high thermal stability Zr50Cu40Al10 metallic glass and its crystallization behavior as compared to Zr70Cu20Al10 Zr70Cu30 glassy alloys, by differential scanning calorimetry (DSC), x-ray diffraction (XRD) resonant ultrasound spectroscopy (RUS) techniques. It was found from XRD DSC analyses that (i) constituent atoms in are highly close-packed a state (ii) shows complicated process when it is heated at conventional heating rates, but rapidly...
The effect of Al content on superelastic properties Ti75−xNb15Zr10Alx (x = 0–6 at%) quaternary β Ti alloys were investigated. And the effects baking for coating or plating also studied. containing 3 and 4 at% clearly exhibited behavior after aging at 453 553 K, which are appropriate temperatures industrial plating, respectively. Ti72Nb15Zr10Al3 alloy largest recovery strain 2.5% due to even plating. In this system, strange non-monotonical change as a function was found.
The cold drawing of cast Cu100−xZrx (x=3, 4 and 5 at%) alloys to the reduction ratio 99.7% was found cause simultaneous achievement ultrahigh tensile strength 1350 1800 MPa high electrical conductivity 30 45%IACS (International Annealed Copper Standard). cold-drawn Cu95Zr5 alloy wire has a well-developed fibrous structure fcc-Cu tetragonal Cu9Zr2 phases. volume phase evaluated be about 76%. A very density internal defects observed inside in alloy. microstructure data suggest that Cu with...
In this study, the chemical states of chromium (Cr), arsenic (As), and selenium (Se) in sewage sludge incineration ash were determined by X-ray absorption fine structure (XAFS) spectroscopy. Sewage was sampled from several facilities, XAFS measurements carried out with a beam line BL01B1 at SPring-8 facility. Cr K-edge near-edge (XANES) spectra suggested that compounds predominantly speciated as Cr(III) fraction Cr(VI) very minor. Compared to reference materials, XANES ashes similar those...