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Takayuki Takasugi - One of the best experts on this subject based on the ideXlab platform.
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Age-Induced Precipitation and Hardening Behavior of Ni3Al Intermetallic Alloys Containing Vanadium
Metals, 2019Co-Authors: Satoshi Semboshi, Ryosuke Sasaki, Yasuyuki Kaneno, Takayuki TakasugiAbstract:L12-type Ni3Al Alloys containing vanadium are potential candidates for solid-solution and age-hardenable alloy systems, according to the Ni3Al-Ni3V pseudo-binary phase diagram. Therefore, herein, variations in the microstructure and mechanical properties of Ni-13 at.% Al-12 at.% V-50 ppm B alloy during isothermal aging were investigated. Alloy specimens were solution-treated at 1323 K for 48 h, quenched in water, and aged at 1073 K to 1173 K. The quenched specimens exhibited a single phase of Ni3Al (L12 structure derived from Al (fcc) structure), while in the aged specimens, numerous fine disk-shaped precipitates identified as Ni3V (D022 structure from orthorhombic structure) were formed on {001} planes of the Ni3Al matrix. The size of the disk-shaped Ni3V precipitates increased gradually with increasing aging period. The hardness and strength of the specimens increased initially during aging at 1073 K to 1173 K, reached a maximum, followed by a subsequent decrease. The age-hardening behavior observed for the specimens can be explained in terms of precipitation of the fine disk-shaped Ni3V precipitates in the Ni3Al matrix. Furthermore, the peak-aged specimens exhibited an increase in yield strength with increasing testing temperature, similar to other L12-type Intermetallic Alloys.
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fine precipitation in the channel region of two phase ni 3 al and ni 3 v Intermetallic Alloys containing mo and w
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2016Co-Authors: Yasuyuki Kaneno, Satoshi Semboshi, Daisuke Edatsugi, Takayuki TakasugiAbstract:Fine precipitation was observed in the channel region of the Ni-based, two-phase Ni3Al and Ni3V Intermetallic Alloys containing Mo and W, which are soluble in the A1 phase at high temperatures but less soluble in the two Intermetallic phases at low temperatures. The fine precipitates were identified as Mo- or W-rich phases (Mo solid solution with a body-centered-cubic (bcc) structure or Ni4W with a tetragonal structure) accompanied by a rigid orientation relationship and a habit plane with the constituent phases in the channel region. Fine precipitation was induced when added elements were substituted for Ni, thus, stabilizing the two Intermetallic phases; however, it was not induced when the two Intermetallic phases were destabilized by the addition of elements to substitute for Al and V. Fine precipitation was induced to a greater extent when Nb was concomitantly added to the Alloys with Mo or W and when the two Intermetallic phases were stabilized. Annealing at temperatures below the eutectoid temperature was necessary to induce fine precipitation in the Alloys containing W. Accordingly, age hardening by annealing did not occur in the Alloys containing Mo but did occur in the Alloys containing W, whose behavior was correlated with the difference in the diffusivity of the Mo and W elements in the two-phase eutectoid microstructures (phases).
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effect of si addition on microstructure and mechanical properties of dual two phase Intermetallic Alloys based on the ni 3 al ni 3 v pseudo binary alloy system
MRS Proceedings, 2015Co-Authors: Yuki Hamada, Yasuyuki Kaneno, Hiroshi Numakura, Takayuki TakasugiAbstract:The effect of Si addition on microstructure and mechanical properties of dual two-phase Intermetallic Alloys was investigated. Si was added to the base alloy composition Ni 75 Al 9 V 13 Nb 3 + 50 wt. ppm B by three substitution ways in which Si was substituted either for Ni, for Al and for V, respectively. The Alloys added with 1 at.% Si showed a dual two-phase microstructure composed of Ni 3 Al (L1 2 ) and Ni 3 V (D0 22 ) phases, while the Alloys added with over 2 at.% Si exhibited the same dual two-phase microstructure but contained third phases. The third phases were G phase (Ni 16 Si 7 Nb 6 ) and A2 phase (the bcc solid solution consisting of Nb and V). Yield and tensile strength of the 1 at.% Si-added Alloys were high in the alloy in which Si was substituted for Al but low in the Alloys in which Si was substituted for Ni or for V, in comparison with those of the base alloy. Tensile elongation was lower than that of the base alloy irrespective of substitution ways. The density of the Si added Alloys was close to or slightly lower than that of the base alloy. Oxidation resistance of the Si added alloy was increased. Si addition to the dual two-phase Intermetallic Alloys is beneficial for reducing the density and enhancing the oxidation resistance without a harmful reduction of strength properties.
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effect of nb and ti addition on microstructure and hardness of dual two phase Intermetallic Alloys based on ni3al ni3v pseudo binary alloy system
Materials Transactions, 2010Co-Authors: K Kawahara, Yasuyuki Kaneno, T Moronaga, Atsushi Kakitsuji, Takayuki TakasugiAbstract:The microstructures and hardness property of dual two-phase Intermetallic Alloys that are composed of various kind of volume fractions of geometrically closed packed (GCP) Ni 3 Al(Ll 2 ) and Ni 3 V(DO 22 ) phases was studied. Higher volume fraction of primary Ni 3 Al precipitates was observed in the Ti and Nb added Alloys when keeping Al content the same. Also, the microstructures in the eutectoid (channel) region consisting of N i 3Al+Ni 3 V were sensitive to alloying addition. The hardness of dual two-phase Intermetallic Alloys was basically explained by mixture rule in hardness between primary Ni 3 Al precipitates and eutectoid region. Nb and Ti addition raised hardness of dual two-phase Intermetallic Alloys by solid solution hardening in the constituent phases. This hardening was more significant in Nb addition than in Ti addition. In addition to hardness owing to the mixture rule, additional hardening arising from interfacial area between primary Ni 3 Al precipitates and eutectoid region was found. With increasing Ni 3 Al/channel (eutectoid) interfacial area, the additional hardening increased. As temperature increases, the additional hardening monotonously decreased for the base and Nb added Alloys but little decreased for the Ti added Alloys.
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microstructural factors affecting hardness property of dual two phase Intermetallic Alloys based on ni3al ni3v pseudo binary alloy system
Intermetallics, 2009Co-Authors: K Kawahara, Yasuyuki Kaneno, Atsushi Kakitsuji, Takayuki TakasugiAbstract:Abstract Dual two-phase Intermetallic Alloys that have alloy compositions of Ni 75 Al x Nb 2.5 V 22.5− x and are composed of geometrically close packed (GCP) Ni 3 Al (L1 2 ) and Ni 3 V (D0 22 ) phases containing Nb were studied, focusing on the relationship between microstructural parameter and high-temperature hardness property. The two-phase microstructures defined by primary Ni 3 Al precipitates and eutectoid (i.e., channel) region (consisting of Ni 3 Al and Ni 3 V phases) were characterized in terms of size, volume fraction and number density of primary Ni 3 Al precipitates. The high-temperature hardness was evaluated as a function of temperature. The volume fraction of primary Ni 3 Al phase precipitates, and interfacial area between primary Ni 3 Al precipitates and channel region were found to be important factors affecting the hardness of the dual two-phase Intermetallic Alloys. Possible mechanisms responsible for the observed extra hardening were discussed, taking the role of interfaces among the constituent phases into consideration.
Yasuyuki Kaneno - One of the best experts on this subject based on the ideXlab platform.
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Age-Induced Precipitation and Hardening Behavior of Ni3Al Intermetallic Alloys Containing Vanadium
Metals, 2019Co-Authors: Satoshi Semboshi, Ryosuke Sasaki, Yasuyuki Kaneno, Takayuki TakasugiAbstract:L12-type Ni3Al Alloys containing vanadium are potential candidates for solid-solution and age-hardenable alloy systems, according to the Ni3Al-Ni3V pseudo-binary phase diagram. Therefore, herein, variations in the microstructure and mechanical properties of Ni-13 at.% Al-12 at.% V-50 ppm B alloy during isothermal aging were investigated. Alloy specimens were solution-treated at 1323 K for 48 h, quenched in water, and aged at 1073 K to 1173 K. The quenched specimens exhibited a single phase of Ni3Al (L12 structure derived from Al (fcc) structure), while in the aged specimens, numerous fine disk-shaped precipitates identified as Ni3V (D022 structure from orthorhombic structure) were formed on {001} planes of the Ni3Al matrix. The size of the disk-shaped Ni3V precipitates increased gradually with increasing aging period. The hardness and strength of the specimens increased initially during aging at 1073 K to 1173 K, reached a maximum, followed by a subsequent decrease. The age-hardening behavior observed for the specimens can be explained in terms of precipitation of the fine disk-shaped Ni3V precipitates in the Ni3Al matrix. Furthermore, the peak-aged specimens exhibited an increase in yield strength with increasing testing temperature, similar to other L12-type Intermetallic Alloys.
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Microstructure and Mechanical Properties of Dual Multi-Phase Intermetallic Alloys Composed of Geometrically Close Packed Ni3X Structures
2016Co-Authors: T. Takasugi, Yasuyuki KanenoAbstract:Abstract. Dual two-phase Intermetallic Alloys composed of geometrically close packed (GCP) structures of Ni3Al(L12) and Ni3V(D022) containing Nb were investigated in terms of the microstructural evolution during low temperature annealing (aging) and the related mechanical properties. The eutectoid region, i.e. the prior Al phase (Ni solid solution) is composed of the lamellar-like structure consisting of Ni3Al(L12) and Ni3V(D022) phases. The lamellar-like structure tended to align along <001> direction and on {001} plane in the prior A1 phase (or the L12 phase). In a wide range of temperature, the dual two-phase Intermetallic Alloys showed high yield and tensile strength, and also reasonable tensile ductility, accompanied with ductile fracture mode
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fine precipitation in the channel region of two phase ni 3 al and ni 3 v Intermetallic Alloys containing mo and w
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2016Co-Authors: Yasuyuki Kaneno, Satoshi Semboshi, Daisuke Edatsugi, Takayuki TakasugiAbstract:Fine precipitation was observed in the channel region of the Ni-based, two-phase Ni3Al and Ni3V Intermetallic Alloys containing Mo and W, which are soluble in the A1 phase at high temperatures but less soluble in the two Intermetallic phases at low temperatures. The fine precipitates were identified as Mo- or W-rich phases (Mo solid solution with a body-centered-cubic (bcc) structure or Ni4W with a tetragonal structure) accompanied by a rigid orientation relationship and a habit plane with the constituent phases in the channel region. Fine precipitation was induced when added elements were substituted for Ni, thus, stabilizing the two Intermetallic phases; however, it was not induced when the two Intermetallic phases were destabilized by the addition of elements to substitute for Al and V. Fine precipitation was induced to a greater extent when Nb was concomitantly added to the Alloys with Mo or W and when the two Intermetallic phases were stabilized. Annealing at temperatures below the eutectoid temperature was necessary to induce fine precipitation in the Alloys containing W. Accordingly, age hardening by annealing did not occur in the Alloys containing Mo but did occur in the Alloys containing W, whose behavior was correlated with the difference in the diffusivity of the Mo and W elements in the two-phase eutectoid microstructures (phases).
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effect of si addition on microstructure and mechanical properties of dual two phase Intermetallic Alloys based on the ni 3 al ni 3 v pseudo binary alloy system
MRS Proceedings, 2015Co-Authors: Yuki Hamada, Yasuyuki Kaneno, Hiroshi Numakura, Takayuki TakasugiAbstract:The effect of Si addition on microstructure and mechanical properties of dual two-phase Intermetallic Alloys was investigated. Si was added to the base alloy composition Ni 75 Al 9 V 13 Nb 3 + 50 wt. ppm B by three substitution ways in which Si was substituted either for Ni, for Al and for V, respectively. The Alloys added with 1 at.% Si showed a dual two-phase microstructure composed of Ni 3 Al (L1 2 ) and Ni 3 V (D0 22 ) phases, while the Alloys added with over 2 at.% Si exhibited the same dual two-phase microstructure but contained third phases. The third phases were G phase (Ni 16 Si 7 Nb 6 ) and A2 phase (the bcc solid solution consisting of Nb and V). Yield and tensile strength of the 1 at.% Si-added Alloys were high in the alloy in which Si was substituted for Al but low in the Alloys in which Si was substituted for Ni or for V, in comparison with those of the base alloy. Tensile elongation was lower than that of the base alloy irrespective of substitution ways. The density of the Si added Alloys was close to or slightly lower than that of the base alloy. Oxidation resistance of the Si added alloy was increased. Si addition to the dual two-phase Intermetallic Alloys is beneficial for reducing the density and enhancing the oxidation resistance without a harmful reduction of strength properties.
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effect of nb and ti addition on microstructure and hardness of dual two phase Intermetallic Alloys based on ni3al ni3v pseudo binary alloy system
Materials Transactions, 2010Co-Authors: K Kawahara, Yasuyuki Kaneno, T Moronaga, Atsushi Kakitsuji, Takayuki TakasugiAbstract:The microstructures and hardness property of dual two-phase Intermetallic Alloys that are composed of various kind of volume fractions of geometrically closed packed (GCP) Ni 3 Al(Ll 2 ) and Ni 3 V(DO 22 ) phases was studied. Higher volume fraction of primary Ni 3 Al precipitates was observed in the Ti and Nb added Alloys when keeping Al content the same. Also, the microstructures in the eutectoid (channel) region consisting of N i 3Al+Ni 3 V were sensitive to alloying addition. The hardness of dual two-phase Intermetallic Alloys was basically explained by mixture rule in hardness between primary Ni 3 Al precipitates and eutectoid region. Nb and Ti addition raised hardness of dual two-phase Intermetallic Alloys by solid solution hardening in the constituent phases. This hardening was more significant in Nb addition than in Ti addition. In addition to hardness owing to the mixture rule, additional hardening arising from interfacial area between primary Ni 3 Al precipitates and eutectoid region was found. With increasing Ni 3 Al/channel (eutectoid) interfacial area, the additional hardening increased. As temperature increases, the additional hardening monotonously decreased for the base and Nb added Alloys but little decreased for the Ti added Alloys.
Y Nunomura - One of the best experts on this subject based on the ideXlab platform.
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phase relation and microstructure in multi phase Intermetallic Alloys based on ni3si ni3ti ni3nb pseudo ternary alloy system
Intermetallics, 2004Co-Authors: Y Nunomura, Yasuyuki Kaneno, Hiroshi Tsuda, Takayuki TakasugiAbstract:Abstract The phase relation and microstructure of Alloys based on the Ni3Al–Ni3Ti–Ni3V pseudo-ternary alloy system at 1273 and 1373 K were investigated by optical microscopy, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy (attached with a wavelength dispersive spectroscope). As the constituent Intermetallic phases at 1273 K, L12(Ni3Al), D024(Ni3Ti), D022(Ni3V) and rhombohedral (Ni3Ti0.7V0.3) were identified and then their phase fields were shown to depend upon the electron concentration (e/a) and the atomic size factor (Rx/RNi) of the constituent atoms. Among four Intermetallic phases identified at 1273 K, five kinds of two-phase relations (i.e. L12–D024, D024–rhombohedral, rhombohedral–D022 D022–D024 and D022–L12) and two kinds of three-phase relations (i.e. L12–D024–D022 and D024–rhombohedral–D022) were found to exist. Also, D024 (Ni3Ti) phase extended up to concentration field in which a majority of constituent Ti elements were replaced by Al and V elements, keeping their concentrations identical. The prepared Alloys exhibited widely different microstructures, depending on alloy composition and temperature. In the low Ti concentration region, dual multi-phase microstructures composed of L12+D024+A1(→L12+D022) were formed by a eutectic reaction.
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phase relation and microstructure in multi phase Intermetallic Alloys based on ni3al ni3nb ni3v pseudo ternary alloy system
Intermetallics, 2004Co-Authors: Y Nunomura, Yasuyuki Kaneno, Hiroshi Tsuda, Takayuki TakasugiAbstract:Abstract The phase relation and microstructure of Alloys based on the Ni3Al–Ni3Ti–Ni3V pseudo-ternary alloy system at 1273 and 1373 K were investigated by optical microscopy, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy (attached with a wavelength dispersive spectroscope). As the constituent Intermetallic phases at 1273 K, L12(Ni3Al), D024(Ni3Ti), D022(Ni3V) and rhombohedral (Ni3Ti0.7V0.3) were identified and then their phase fields were shown to depend upon the electron concentration (e/a) and the atomic size factor (Rx/RNi) of the constituent atoms. Among four Intermetallic phases identified at 1273 K, five kinds of two-phase relations (i.e. L12–D024, D024–rhombohedral, rhombohedral–D022 D022–D024 and D022–L12) and two kinds of three-phase relations (i.e. L12–D024–D022 and D024–rhombohedral–D022) were found to exist. Also, D024 (Ni3Ti) phase extended up to concentration field in which a majority of constituent Ti elements were replaced by Al and V elements, keeping their concentrations identical. The prepared Alloys exhibited widely different microstructures, depending on alloy composition and temperature. In the low Ti concentration region, dual multi-phase microstructures composed of L12+D024+A1(→L12+D022) were formed by a eutectic reaction.
Hiroshi Tsuda - One of the best experts on this subject based on the ideXlab platform.
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phase relation and microstructure in multi phase Intermetallic Alloys based on ni3si ni3ti ni3nb pseudo ternary alloy system
Intermetallics, 2004Co-Authors: Y Nunomura, Yasuyuki Kaneno, Hiroshi Tsuda, Takayuki TakasugiAbstract:Abstract The phase relation and microstructure of Alloys based on the Ni3Al–Ni3Ti–Ni3V pseudo-ternary alloy system at 1273 and 1373 K were investigated by optical microscopy, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy (attached with a wavelength dispersive spectroscope). As the constituent Intermetallic phases at 1273 K, L12(Ni3Al), D024(Ni3Ti), D022(Ni3V) and rhombohedral (Ni3Ti0.7V0.3) were identified and then their phase fields were shown to depend upon the electron concentration (e/a) and the atomic size factor (Rx/RNi) of the constituent atoms. Among four Intermetallic phases identified at 1273 K, five kinds of two-phase relations (i.e. L12–D024, D024–rhombohedral, rhombohedral–D022 D022–D024 and D022–L12) and two kinds of three-phase relations (i.e. L12–D024–D022 and D024–rhombohedral–D022) were found to exist. Also, D024 (Ni3Ti) phase extended up to concentration field in which a majority of constituent Ti elements were replaced by Al and V elements, keeping their concentrations identical. The prepared Alloys exhibited widely different microstructures, depending on alloy composition and temperature. In the low Ti concentration region, dual multi-phase microstructures composed of L12+D024+A1(→L12+D022) were formed by a eutectic reaction.
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phase relation and microstructure in multi phase Intermetallic Alloys based on ni3al ni3nb ni3v pseudo ternary alloy system
Intermetallics, 2004Co-Authors: Y Nunomura, Yasuyuki Kaneno, Hiroshi Tsuda, Takayuki TakasugiAbstract:Abstract The phase relation and microstructure of Alloys based on the Ni3Al–Ni3Ti–Ni3V pseudo-ternary alloy system at 1273 and 1373 K were investigated by optical microscopy, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy (attached with a wavelength dispersive spectroscope). As the constituent Intermetallic phases at 1273 K, L12(Ni3Al), D024(Ni3Ti), D022(Ni3V) and rhombohedral (Ni3Ti0.7V0.3) were identified and then their phase fields were shown to depend upon the electron concentration (e/a) and the atomic size factor (Rx/RNi) of the constituent atoms. Among four Intermetallic phases identified at 1273 K, five kinds of two-phase relations (i.e. L12–D024, D024–rhombohedral, rhombohedral–D022 D022–D024 and D022–L12) and two kinds of three-phase relations (i.e. L12–D024–D022 and D024–rhombohedral–D022) were found to exist. Also, D024 (Ni3Ti) phase extended up to concentration field in which a majority of constituent Ti elements were replaced by Al and V elements, keeping their concentrations identical. The prepared Alloys exhibited widely different microstructures, depending on alloy composition and temperature. In the low Ti concentration region, dual multi-phase microstructures composed of L12+D024+A1(→L12+D022) were formed by a eutectic reaction.
K Kawahara - One of the best experts on this subject based on the ideXlab platform.
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effect of nb and ti addition on microstructure and hardness of dual two phase Intermetallic Alloys based on ni3al ni3v pseudo binary alloy system
Materials Transactions, 2010Co-Authors: K Kawahara, Yasuyuki Kaneno, T Moronaga, Atsushi Kakitsuji, Takayuki TakasugiAbstract:The microstructures and hardness property of dual two-phase Intermetallic Alloys that are composed of various kind of volume fractions of geometrically closed packed (GCP) Ni 3 Al(Ll 2 ) and Ni 3 V(DO 22 ) phases was studied. Higher volume fraction of primary Ni 3 Al precipitates was observed in the Ti and Nb added Alloys when keeping Al content the same. Also, the microstructures in the eutectoid (channel) region consisting of N i 3Al+Ni 3 V were sensitive to alloying addition. The hardness of dual two-phase Intermetallic Alloys was basically explained by mixture rule in hardness between primary Ni 3 Al precipitates and eutectoid region. Nb and Ti addition raised hardness of dual two-phase Intermetallic Alloys by solid solution hardening in the constituent phases. This hardening was more significant in Nb addition than in Ti addition. In addition to hardness owing to the mixture rule, additional hardening arising from interfacial area between primary Ni 3 Al precipitates and eutectoid region was found. With increasing Ni 3 Al/channel (eutectoid) interfacial area, the additional hardening increased. As temperature increases, the additional hardening monotonously decreased for the base and Nb added Alloys but little decreased for the Ti added Alloys.
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microstructural factors affecting hardness property of dual two phase Intermetallic Alloys based on ni3al ni3v pseudo binary alloy system
Intermetallics, 2009Co-Authors: K Kawahara, Yasuyuki Kaneno, Atsushi Kakitsuji, Takayuki TakasugiAbstract:Abstract Dual two-phase Intermetallic Alloys that have alloy compositions of Ni 75 Al x Nb 2.5 V 22.5− x and are composed of geometrically close packed (GCP) Ni 3 Al (L1 2 ) and Ni 3 V (D0 22 ) phases containing Nb were studied, focusing on the relationship between microstructural parameter and high-temperature hardness property. The two-phase microstructures defined by primary Ni 3 Al precipitates and eutectoid (i.e., channel) region (consisting of Ni 3 Al and Ni 3 V phases) were characterized in terms of size, volume fraction and number density of primary Ni 3 Al precipitates. The high-temperature hardness was evaluated as a function of temperature. The volume fraction of primary Ni 3 Al phase precipitates, and interfacial area between primary Ni 3 Al precipitates and channel region were found to be important factors affecting the hardness of the dual two-phase Intermetallic Alloys. Possible mechanisms responsible for the observed extra hardening were discussed, taking the role of interfaces among the constituent phases into consideration.
