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Synchrotron high energy X-ray diffraction study of microstructure evolution of severely cold drawn NiTi wire during annealing
Microstructure evolution of a cold-drawn NiTi shape memory alloy wire was investigated by means of in-situ synchrotron high-energy X-ray diffraction during continuous heating. The cold-drawn wire contained amorphous regions and nano-crystalline domains in its microstructure. Pair distribution function analysis revealed that the amorphous regions underwent structural relaxation via atomic rearrangement when heated above 100 °C. The nano-crystalline domains were found to exhibit a strong cold work induced lattice strain anisotropy having a preferential <111> fiber orientation along the wire axial direction. The lattice strain anisotropy systematically decreased upon heating above 200 °C, implying a structural recovery. A broad conical texture was formed in the wire specimen after crystallization similar in detail to the initial <111> texture axial orientation of the nano-crystalline domains produced by the severe cold wire drawing deformation.
Composition dependent order-disorder transition in Nd Zr1−O2−0.5 pyrochlores: A combined structural, calorimetric and ab initio modeling study
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Comparative studies on thermoelectric properties of p-type Mg2Sn0.75Ge0.25 doped with lithium, sodium, and gallium
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Tunability of martensitic transformation in Mg-Sc shape memory alloys: A DFT study
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In situ and ex situ studies of anomalous eutectic formation in undercooled Ni–Sn alloys
Anomalous eutectic formation in undercooled Ni-Sn alloys was investigated by in situ X-ray diffraction and ex situ remelting and annealing experiments. Dynamic recrystallization and partial remelting of primary solids followed by repeated nucleation and growth of eutectic grains in the mushy zone were revealed by time-resolved X-ray diffraction. Ex situ experiments demonstrated that partial remelting of near-equilibrium solidified alloys of eutectic or near-eutectic composition can convert regular lamellar eutectic into anomalous eutectic, whereas high-temperature annealing of splat-quenched alloys of similar composition can convert eutectic or two-phase dendrites into anomalous eutectic. It is concluded that compared to ripening in solid-states, partial remelting of eutectic or two-phase dendrites in a mushy zone provides a more realistic mechanism for anomalous eutectic formation in undercooled solidification of Ni-Sn eutectic alloys. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
In-situ high energy X-ray diffraction study of the elastic response of a metastable β-titanium alloy
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Site-specific study of jetting, bonding, and local deformation during high-velocity metallic microparticle impact
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Quantitative in-situ study of strength-governed interfacial failure between h-BN and polymer-derived ceramic
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Characterization of Ni@Pt and Co@Pt overlayer catalystsusing XAS studies
Abstract not provided
In-situ X-ray absorption study of ceria-supported Pd-Cu nanoparticles for oxygen-enhanced water gas shift
Abstract not provided
A periodic-DFT study of retro-aldol fragmentation of fuctose on MoO3
Not Available
Study on heat and power decoupling for CCHP system: Methodology and case study
Not Available