The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Akihisa Inoue - One of the best experts on this subject based on the ideXlab platform.
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Production of single Al64Cu23Fe13 icosahedral quasicrystal with the Czochralski Method
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Abstract We have investigated formation mechanisms of the icosahedral (i-) phase in a Cu-enriched region of the Al–Cu–Fe system. The formation of i-phase in the Al–Cu–Fe alloy system is characterized by the peritectic reaction: λ 2 +L→I (λ 2 is an Al 3 Fe compound with over 5 at.% Cu), which has been observed even in the Cu-enriched region. Therefore, we have tried to avoid the λ 2 -crystallization by preliminary metallurgical treatments for molten alloy. As a result, we have succeeded in growing a single Al 64 Cu 23 Fe 13 i-quasicrystal with the Czochralski Method.
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Growth of a single Al64Cu23Fe13 icosahedral quasicrystal using the Czochralski Method and annealing removal of strains
Materials Transactions JIM, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Phase relations between the liquid and the solid icosahedral (I-) phases were examined at different temperatures to determine the growth condition of a single Al-Cu-Fe I-quasicrystal using the Czochralski Method. The composition of the single I-quasicrystal was chosen to be Al 64 Cu 23 Fe 13 due to the superior thermal stability. We found that the liquid composition, which equilibrates to the Al 64 Cu 23 Fe 13 I-phase at 1073 K, was Al 57.7 Cu 37.7 Fe 3.5 Si 1.1 . Based on the phase relation, production of a single Al 64 Cu 23 Fe 13 I-quasicrystal was attempted by using the Czochralski Method. As a result, we succeeded in the growth of a single Al 64 Cu 23 Fe 13 I-quasicrystal, and we also measured the Vickers hardness of annealed single I-quasicrystal samples with different anneal times to estimate the structural improvement by annealing.
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preparation of decagonal al ni co single quasicrystal by Czochralski Method
Materials Transactions Jim, 1997Co-Authors: Yoshihiko Yokoyama, Kenzo Fukaura, Akihisa Inoue, S Kimura, H SunadaAbstract:We constructed a partial isothermal phase diagram including a decagonal (d-) phase in the Al-Ni-Co system and determined the composition of the liquid in equilibrium with the stoichiometric d-phase. The d-phase is formed through a peritectic reaction between the B2 phase and the liquid phase. A seed d-phase prepared by selecting an optimum composition of the liquid phase was used for growing a large-scale d-quasicrystal by the Czochralski Method. As a result, we have product a single decagonal quasicrystal with the size of 60 mm in length and 1 to 7 mm in diameter and the mean composition of Al 72.2 Ni 12.1 Co 15.7 .
Yoshihiko Yokoyama - One of the best experts on this subject based on the ideXlab platform.
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Growth condition and X-ray analysis of single Al64Cu23Fe13 icosahedral quasicrystal by the Czochralski Method
MATERIALS TRANSACTIONS, 2002Co-Authors: Yoshihiko Yokoyama, Yoshie Matsuo, Kazuki Yamamoto, Kenji HiragaAbstract:Growth conditions for the preparation of a single Al 64 Cu 23 Fe 13 icosahedral (1-) quasicrystal with excellent quasicrystallinity were examined using the Czochralski Method. The appreciation of the quasicrystallinity of the grown single quasicrystal was performed by X-ray structural analysts. The full widths at half-maximum (FWHM) of the Bragg reflections along 2-, 3- and 5-fold symmetry directions have no Q || and Q⊥ dependence. Where the Q || and Q⊥ mean the phason momentum and real scattering vector. Furthermore, peak shifts from ideal Bragg positions were not observed. These means that the grown Al 64 Cu 23 Fe 13 quasicrystal by the Czochralski Method has perfect I-phase structure.
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Production of single Al64Cu23Fe13 icosahedral quasicrystal with the Czochralski Method
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Abstract We have investigated formation mechanisms of the icosahedral (i-) phase in a Cu-enriched region of the Al–Cu–Fe system. The formation of i-phase in the Al–Cu–Fe alloy system is characterized by the peritectic reaction: λ 2 +L→I (λ 2 is an Al 3 Fe compound with over 5 at.% Cu), which has been observed even in the Cu-enriched region. Therefore, we have tried to avoid the λ 2 -crystallization by preliminary metallurgical treatments for molten alloy. As a result, we have succeeded in growing a single Al 64 Cu 23 Fe 13 i-quasicrystal with the Czochralski Method.
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Growth of a single Al64Cu23Fe13 icosahedral quasicrystal using the Czochralski Method and annealing removal of strains
Materials Transactions JIM, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Phase relations between the liquid and the solid icosahedral (I-) phases were examined at different temperatures to determine the growth condition of a single Al-Cu-Fe I-quasicrystal using the Czochralski Method. The composition of the single I-quasicrystal was chosen to be Al 64 Cu 23 Fe 13 due to the superior thermal stability. We found that the liquid composition, which equilibrates to the Al 64 Cu 23 Fe 13 I-phase at 1073 K, was Al 57.7 Cu 37.7 Fe 3.5 Si 1.1 . Based on the phase relation, production of a single Al 64 Cu 23 Fe 13 I-quasicrystal was attempted by using the Czochralski Method. As a result, we succeeded in the growth of a single Al 64 Cu 23 Fe 13 I-quasicrystal, and we also measured the Vickers hardness of annealed single I-quasicrystal samples with different anneal times to estimate the structural improvement by annealing.
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preparation of decagonal al ni co single quasicrystal by Czochralski Method
Materials Transactions Jim, 1997Co-Authors: Yoshihiko Yokoyama, Kenzo Fukaura, Akihisa Inoue, S Kimura, H SunadaAbstract:We constructed a partial isothermal phase diagram including a decagonal (d-) phase in the Al-Ni-Co system and determined the composition of the liquid in equilibrium with the stoichiometric d-phase. The d-phase is formed through a peritectic reaction between the B2 phase and the liquid phase. A seed d-phase prepared by selecting an optimum composition of the liquid phase was used for growing a large-scale d-quasicrystal by the Czochralski Method. As a result, we have product a single decagonal quasicrystal with the size of 60 mm in length and 1 to 7 mm in diameter and the mean composition of Al 72.2 Ni 12.1 Co 15.7 .
H Sunada - One of the best experts on this subject based on the ideXlab platform.
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Production of single Al64Cu23Fe13 icosahedral quasicrystal with the Czochralski Method
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Abstract We have investigated formation mechanisms of the icosahedral (i-) phase in a Cu-enriched region of the Al–Cu–Fe system. The formation of i-phase in the Al–Cu–Fe alloy system is characterized by the peritectic reaction: λ 2 +L→I (λ 2 is an Al 3 Fe compound with over 5 at.% Cu), which has been observed even in the Cu-enriched region. Therefore, we have tried to avoid the λ 2 -crystallization by preliminary metallurgical treatments for molten alloy. As a result, we have succeeded in growing a single Al 64 Cu 23 Fe 13 i-quasicrystal with the Czochralski Method.
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Growth of a single Al64Cu23Fe13 icosahedral quasicrystal using the Czochralski Method and annealing removal of strains
Materials Transactions JIM, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Phase relations between the liquid and the solid icosahedral (I-) phases were examined at different temperatures to determine the growth condition of a single Al-Cu-Fe I-quasicrystal using the Czochralski Method. The composition of the single I-quasicrystal was chosen to be Al 64 Cu 23 Fe 13 due to the superior thermal stability. We found that the liquid composition, which equilibrates to the Al 64 Cu 23 Fe 13 I-phase at 1073 K, was Al 57.7 Cu 37.7 Fe 3.5 Si 1.1 . Based on the phase relation, production of a single Al 64 Cu 23 Fe 13 I-quasicrystal was attempted by using the Czochralski Method. As a result, we succeeded in the growth of a single Al 64 Cu 23 Fe 13 I-quasicrystal, and we also measured the Vickers hardness of annealed single I-quasicrystal samples with different anneal times to estimate the structural improvement by annealing.
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preparation of decagonal al ni co single quasicrystal by Czochralski Method
Materials Transactions Jim, 1997Co-Authors: Yoshihiko Yokoyama, Kenzo Fukaura, Akihisa Inoue, S Kimura, H SunadaAbstract:We constructed a partial isothermal phase diagram including a decagonal (d-) phase in the Al-Ni-Co system and determined the composition of the liquid in equilibrium with the stoichiometric d-phase. The d-phase is formed through a peritectic reaction between the B2 phase and the liquid phase. A seed d-phase prepared by selecting an optimum composition of the liquid phase was used for growing a large-scale d-quasicrystal by the Czochralski Method. As a result, we have product a single decagonal quasicrystal with the size of 60 mm in length and 1 to 7 mm in diameter and the mean composition of Al 72.2 Ni 12.1 Co 15.7 .
A. Pajaczkowska - One of the best experts on this subject based on the ideXlab platform.
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Growth of GdCa4O(BO3)3 by the Czochralski Method and Some Structure Properties
Crystal Growth & Design, 2001Co-Authors: A. Pajaczkowska, A. Klos, B. Hilczer, And N. Menguy, A. NovosselovAbstract:Self-frequency doubling calcium oxoborate compounds GdCa4O(BO3)3 were prepared as a single crystal by the Czochralski Method. To reveal the nature and the distribution of defects, crystals were investigated by chemical etching, X-ray Methods, high-resolution electron microscopy (HREM), and Raman spectroscopy. XPS measurements were performed to reveal the impurity of the single crystal. GCOB crystal showed high ordering in the lattice up to room temperature.
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Twinning structure of LaGaO3 grown by the Czochralski Method
Journal of Materials Science, 1992Co-Authors: J. Fink-finowicki, Marek Berkowski, A. PajaczkowskaAbstract:Crystals of lanthanum gallate were grown by the Czochralski Method and their quality was tested by microscopic observation in polarized light. This material is used as a substratum for the epitaxial growth of highTc films of YBCO, particularly for certain high-frequency device applications. Two types of twins were observed and the difference in their temperature behaviour is discussed. The best quality single crystals (practically without twins) were obtained with the 〈101〉 and 〈100〉 seeds.
Kenji Hiraga - One of the best experts on this subject based on the ideXlab platform.
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Growth condition and X-ray analysis of single Al64Cu23Fe13 icosahedral quasicrystal by the Czochralski Method
MATERIALS TRANSACTIONS, 2002Co-Authors: Yoshihiko Yokoyama, Yoshie Matsuo, Kazuki Yamamoto, Kenji HiragaAbstract:Growth conditions for the preparation of a single Al 64 Cu 23 Fe 13 icosahedral (1-) quasicrystal with excellent quasicrystallinity were examined using the Czochralski Method. The appreciation of the quasicrystallinity of the grown single quasicrystal was performed by X-ray structural analysts. The full widths at half-maximum (FWHM) of the Bragg reflections along 2-, 3- and 5-fold symmetry directions have no Q || and Q⊥ dependence. Where the Q || and Q⊥ mean the phason momentum and real scattering vector. Furthermore, peak shifts from ideal Bragg positions were not observed. These means that the grown Al 64 Cu 23 Fe 13 quasicrystal by the Czochralski Method has perfect I-phase structure.
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Production of single Al64Cu23Fe13 icosahedral quasicrystal with the Czochralski Method
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Abstract We have investigated formation mechanisms of the icosahedral (i-) phase in a Cu-enriched region of the Al–Cu–Fe system. The formation of i-phase in the Al–Cu–Fe alloy system is characterized by the peritectic reaction: λ 2 +L→I (λ 2 is an Al 3 Fe compound with over 5 at.% Cu), which has been observed even in the Cu-enriched region. Therefore, we have tried to avoid the λ 2 -crystallization by preliminary metallurgical treatments for molten alloy. As a result, we have succeeded in growing a single Al 64 Cu 23 Fe 13 i-quasicrystal with the Czochralski Method.
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Growth of a single Al64Cu23Fe13 icosahedral quasicrystal using the Czochralski Method and annealing removal of strains
Materials Transactions JIM, 2000Co-Authors: Yoshihiko Yokoyama, Kenji Hiraga, Kenzo Fukaura, H Sunada, Akihisa InoueAbstract:Phase relations between the liquid and the solid icosahedral (I-) phases were examined at different temperatures to determine the growth condition of a single Al-Cu-Fe I-quasicrystal using the Czochralski Method. The composition of the single I-quasicrystal was chosen to be Al 64 Cu 23 Fe 13 due to the superior thermal stability. We found that the liquid composition, which equilibrates to the Al 64 Cu 23 Fe 13 I-phase at 1073 K, was Al 57.7 Cu 37.7 Fe 3.5 Si 1.1 . Based on the phase relation, production of a single Al 64 Cu 23 Fe 13 I-quasicrystal was attempted by using the Czochralski Method. As a result, we succeeded in the growth of a single Al 64 Cu 23 Fe 13 I-quasicrystal, and we also measured the Vickers hardness of annealed single I-quasicrystal samples with different anneal times to estimate the structural improvement by annealing.
