The Experts below are selected from a list of 192 Experts worldwide ranked by ideXlab platform
Alessandro Mottura - One of the best experts on this subject based on the ideXlab platform.
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first principles modeling of the temperature dependence for the superlattice Intrinsic Stacking Fault energies in l1 _ ni _ 75 x 75 xx _x xal _ 5 5 alloys
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2018Co-Authors: Joshua Allen, Alessandro Mottura, A BreidiAbstract:Stronger and more resistant alloys are required in order to increase the performance and efficiency of jet engines and gas turbines. This will eventually require planar Faults engineering, or a complete understanding of the effects of composition and temperature on the various planar Faults that arise as a result of shearing of the \(\gamma ^\prime \) precipitates. In the current study, a combined scheme consisting of the density functional theory, the quasi-harmonic Debye model, and the axial Ising model, in conjunction with a quasistatic approach is used to assess the effects of composition and temperature of a series of pseudo-binary alloys based on the \(({\mathrm{Ni}}_{75-x}{\mathrm{X}}_{x}){\mathrm{Al}}_{25}\) system using distinct relaxation schemes to assess observed differences. Our calculations reveal that the (111) superlattice Intrinsic Stacking Fault energies in these systems decline modestly with temperature between \(0\,\)K and \(1000\,\)K.
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First-Principles Modeling of the Temperature Dependence for the Superlattice Intrinsic Stacking Fault Energies in L1$$_$$ Ni$$_{75-x}$$75-xX$$_x$$xAl$$_{5}$$5 Alloys
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2018Co-Authors: Joshua Allen, Alessandro Mottura, A BreidiAbstract:Stronger and more resistant alloys are required in order to increase the performance and efficiency of jet engines and gas turbines. This will eventually require planar Faults engineering, or a complete understanding of the effects of composition and temperature on the various planar Faults that arise as a result of shearing of the \(\gamma ^\prime \) precipitates. In the current study, a combined scheme consisting of the density functional theory, the quasi-harmonic Debye model, and the axial Ising model, in conjunction with a quasistatic approach is used to assess the effects of composition and temperature of a series of pseudo-binary alloys based on the \(({\mathrm{Ni}}_{75-x}{\mathrm{X}}_{x}){\mathrm{Al}}_{25}\) system using distinct relaxation schemes to assess observed differences. Our calculations reveal that the (111) superlattice Intrinsic Stacking Fault energies in these systems decline modestly with temperature between \(0\,\)K and \(1000\,\)K.
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first principles modeling of superlattice Intrinsic Stacking Fault energies in ni3al based alloys
Acta Materialia, 2018Co-Authors: A Breidi, Joshua Allen, Alessandro MotturaAbstract:Abstract High-throughput quantum mechanics based simulations have been carried out to establish the change in lattice parameter and superlattice Intrinsic Stacking Fault (SISF) formation energies in Ni3Al-based alloys using the axial Ising model. We had direct access to the variation in SISF energies due to finite compositional change of the added ternary transition metal (TM) element through constructing large supercells, which was equally necessary to account for chemical disorder. We find that most added TM ternaries induce an important quasi-linear increase in the SISF energy as a function of alloying composition x. The most pronounced increase corresponds to Fe addition, while Co addition decreases the SISF energy monotonically. Our results shed light on the role played by TM elements on strengthening L12 Ni3Al precipitates against Stacking Fault shear. The data are of high importance for designing new Ni-based superalloys based on computational approaches.
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a first principles study of the effect of ta on the superlattice Intrinsic Stacking Fault energy of l12 co3 al w
Intermetallics, 2012Co-Authors: Alessandro Mottura, Anderson Janotti, Tresa M PollockAbstract:Abstract New Co-based alloys containing a L12 reinforcement phase display exceptional high-temperature properties. Early research has shown that the quaternary alloy Co-8.8Al-9.8W-2Ta (at.%) has a high-temperature strength comparable to single-crystal Ni-based superalloys above 1200 K. Associated with high strength is an unusual high density of Intrinsic Stacking Faults within the γ′ precipitates. In this work, Density Functional Theory, the Axial Next Nearest Neighbor Ising model and Special Quasi-random Structures have been used to calculate the Stacking Fault energy of L12-Co3(Al,W) and the effect of small Ta additions on the Stacking Fault energy. The model predicts a superlattice Intrinsic Stacking Fault energy of 90–93 mJ/m2, which increases up to 30% when one Ta atom is substituted on the Al/W sub-lattice. This effect can be explained by considering d-band effects resulting from the addition of Ta.
Ryan B. Wicker - One of the best experts on this subject based on the ideXlab platform.
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microstructure and mechanical properties of open cellular biomaterials prototypes for total knee replacement implants fabricated by electron beam melting
Journal of The Mechanical Behavior of Biomedical Materials, 2011Co-Authors: Lawrence E Murr, Edwin Martinez, Y. X. Tian, Patrick W. Shindo, X.y. Cheng, Sara M. Gaytan, Francisco Medina, Krista Amato, Shujun Li, Ryan B. WickerAbstract:Total knee replacement implants consisting of a Co-29Cr-6Mo alloy femoral component and a Ti-6Al-4V tibial component are the basis for the additive manufacturing of novel solid, mesh, and foam monoliths using electron beam melting (EBM). Ti-6Al-4V solid prototype microstructures were primarily alpha-phase acicular platelets while the mesh and foam structures were characterized by alpha'-martensite with some residual alpha. The Co-29Cr-6Mo containing 0.22% C formed columnar (directional) Cr(23)C(6) carbides spaced similar to 2 mu m in the build direction, while HIP-annealed Co-Cr alloy exhibited an Intrinsic Stacking Fault microstructure. A log-log plot of relative stiffness versus relative density for Ti-6Al-4V and Co-29Cr-6Mo open-cellular mesh and foams resulted in a fitted line with a nearly ideal slope, n = 2.1. A stress shielding design graph constructed from these data permitted mesh and foam implant prototypes to be fabricated for compatible bone stiffness. (C) 2011 Elsevier Ltd. All rights reserved.
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Microstructure and mechanical properties of open-cellular biomaterials prototypes for total knee replacement implants fabricated by electron beam melting
Journal of the Mechanical Behavior of Biomedical Materials, 2011Co-Authors: Lawrence E Murr, Edwin Martinez, Y. X. Tian, Krista N. Amato, Patrick W. Shindo, S.j. Li, X.y. Cheng, Sara M. Gaytan, Frank Medina, Francisco Medina, Ryan B. WickerAbstract:Total knee replacement implants consisting of a Co-29Cr-6Mo alloy femoral component and a Ti-6Al-4V tibial component are the basis for the additive manufacturing of novel solid, mesh, and foam monoliths using electron beam melting (EBM). Ti-6Al-4V solid prototype microstructures were primarily α-phase acicular platelets while the mesh and foam structures were characterized by α'-martensite with some residual α. The Co-29Cr-6Mo containing 0.22% C formed columnar (directional) Cr23C6carbides spaced ~2 μm in the build direction, while HIP-annealed Co-Cr alloy exhibited an Intrinsic Stacking Fault microstructure. A log-log plot of relative stiffness versus relative density for Ti-6Al-4V and Co-29Cr-6Mo open-cellular mesh and foams resulted in a fitted line with a nearly ideal slope, n=2.1. A stress shielding design graph constructed from these data permitted mesh and foam implant prototypes to be fabricated for compatible bone stiffness. © 2011 Elsevier Ltd.
A Breidi - One of the best experts on this subject based on the ideXlab platform.
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First-Principles Modeling of the Temperature Dependence for the Superlattice Intrinsic Stacking Fault Energies in L1$$_$$ Ni$$_{75-x}$$75-xX$$_x$$xAl$$_{5}$$5 Alloys
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2018Co-Authors: Joshua Allen, Alessandro Mottura, A BreidiAbstract:Stronger and more resistant alloys are required in order to increase the performance and efficiency of jet engines and gas turbines. This will eventually require planar Faults engineering, or a complete understanding of the effects of composition and temperature on the various planar Faults that arise as a result of shearing of the \(\gamma ^\prime \) precipitates. In the current study, a combined scheme consisting of the density functional theory, the quasi-harmonic Debye model, and the axial Ising model, in conjunction with a quasistatic approach is used to assess the effects of composition and temperature of a series of pseudo-binary alloys based on the \(({\mathrm{Ni}}_{75-x}{\mathrm{X}}_{x}){\mathrm{Al}}_{25}\) system using distinct relaxation schemes to assess observed differences. Our calculations reveal that the (111) superlattice Intrinsic Stacking Fault energies in these systems decline modestly with temperature between \(0\,\)K and \(1000\,\)K.
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first principles modeling of the temperature dependence for the superlattice Intrinsic Stacking Fault energies in l1 _ ni _ 75 x 75 xx _x xal _ 5 5 alloys
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2018Co-Authors: Joshua Allen, Alessandro Mottura, A BreidiAbstract:Stronger and more resistant alloys are required in order to increase the performance and efficiency of jet engines and gas turbines. This will eventually require planar Faults engineering, or a complete understanding of the effects of composition and temperature on the various planar Faults that arise as a result of shearing of the \(\gamma ^\prime \) precipitates. In the current study, a combined scheme consisting of the density functional theory, the quasi-harmonic Debye model, and the axial Ising model, in conjunction with a quasistatic approach is used to assess the effects of composition and temperature of a series of pseudo-binary alloys based on the \(({\mathrm{Ni}}_{75-x}{\mathrm{X}}_{x}){\mathrm{Al}}_{25}\) system using distinct relaxation schemes to assess observed differences. Our calculations reveal that the (111) superlattice Intrinsic Stacking Fault energies in these systems decline modestly with temperature between \(0\,\)K and \(1000\,\)K.
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first principles modeling of superlattice Intrinsic Stacking Fault energies in ni3al based alloys
Acta Materialia, 2018Co-Authors: A Breidi, Joshua Allen, Alessandro MotturaAbstract:Abstract High-throughput quantum mechanics based simulations have been carried out to establish the change in lattice parameter and superlattice Intrinsic Stacking Fault (SISF) formation energies in Ni3Al-based alloys using the axial Ising model. We had direct access to the variation in SISF energies due to finite compositional change of the added ternary transition metal (TM) element through constructing large supercells, which was equally necessary to account for chemical disorder. We find that most added TM ternaries induce an important quasi-linear increase in the SISF energy as a function of alloying composition x. The most pronounced increase corresponds to Fe addition, while Co addition decreases the SISF energy monotonically. Our results shed light on the role played by TM elements on strengthening L12 Ni3Al precipitates against Stacking Fault shear. The data are of high importance for designing new Ni-based superalloys based on computational approaches.
Lawrence E Murr - One of the best experts on this subject based on the ideXlab platform.
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microstructure and mechanical properties of open cellular biomaterials prototypes for total knee replacement implants fabricated by electron beam melting
Journal of The Mechanical Behavior of Biomedical Materials, 2011Co-Authors: Lawrence E Murr, Edwin Martinez, Y. X. Tian, Patrick W. Shindo, X.y. Cheng, Sara M. Gaytan, Francisco Medina, Krista Amato, Shujun Li, Ryan B. WickerAbstract:Total knee replacement implants consisting of a Co-29Cr-6Mo alloy femoral component and a Ti-6Al-4V tibial component are the basis for the additive manufacturing of novel solid, mesh, and foam monoliths using electron beam melting (EBM). Ti-6Al-4V solid prototype microstructures were primarily alpha-phase acicular platelets while the mesh and foam structures were characterized by alpha'-martensite with some residual alpha. The Co-29Cr-6Mo containing 0.22% C formed columnar (directional) Cr(23)C(6) carbides spaced similar to 2 mu m in the build direction, while HIP-annealed Co-Cr alloy exhibited an Intrinsic Stacking Fault microstructure. A log-log plot of relative stiffness versus relative density for Ti-6Al-4V and Co-29Cr-6Mo open-cellular mesh and foams resulted in a fitted line with a nearly ideal slope, n = 2.1. A stress shielding design graph constructed from these data permitted mesh and foam implant prototypes to be fabricated for compatible bone stiffness. (C) 2011 Elsevier Ltd. All rights reserved.
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Microstructure and mechanical properties of open-cellular biomaterials prototypes for total knee replacement implants fabricated by electron beam melting
Journal of the Mechanical Behavior of Biomedical Materials, 2011Co-Authors: Lawrence E Murr, Edwin Martinez, Y. X. Tian, Krista N. Amato, Patrick W. Shindo, S.j. Li, X.y. Cheng, Sara M. Gaytan, Frank Medina, Francisco Medina, Ryan B. WickerAbstract:Total knee replacement implants consisting of a Co-29Cr-6Mo alloy femoral component and a Ti-6Al-4V tibial component are the basis for the additive manufacturing of novel solid, mesh, and foam monoliths using electron beam melting (EBM). Ti-6Al-4V solid prototype microstructures were primarily α-phase acicular platelets while the mesh and foam structures were characterized by α'-martensite with some residual α. The Co-29Cr-6Mo containing 0.22% C formed columnar (directional) Cr23C6carbides spaced ~2 μm in the build direction, while HIP-annealed Co-Cr alloy exhibited an Intrinsic Stacking Fault microstructure. A log-log plot of relative stiffness versus relative density for Ti-6Al-4V and Co-29Cr-6Mo open-cellular mesh and foams resulted in a fitted line with a nearly ideal slope, n=2.1. A stress shielding design graph constructed from these data permitted mesh and foam implant prototypes to be fabricated for compatible bone stiffness. © 2011 Elsevier Ltd.
Joshua Allen - One of the best experts on this subject based on the ideXlab platform.
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First-Principles Modeling of the Temperature Dependence for the Superlattice Intrinsic Stacking Fault Energies in L1$$_$$ Ni$$_{75-x}$$75-xX$$_x$$xAl$$_{5}$$5 Alloys
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2018Co-Authors: Joshua Allen, Alessandro Mottura, A BreidiAbstract:Stronger and more resistant alloys are required in order to increase the performance and efficiency of jet engines and gas turbines. This will eventually require planar Faults engineering, or a complete understanding of the effects of composition and temperature on the various planar Faults that arise as a result of shearing of the \(\gamma ^\prime \) precipitates. In the current study, a combined scheme consisting of the density functional theory, the quasi-harmonic Debye model, and the axial Ising model, in conjunction with a quasistatic approach is used to assess the effects of composition and temperature of a series of pseudo-binary alloys based on the \(({\mathrm{Ni}}_{75-x}{\mathrm{X}}_{x}){\mathrm{Al}}_{25}\) system using distinct relaxation schemes to assess observed differences. Our calculations reveal that the (111) superlattice Intrinsic Stacking Fault energies in these systems decline modestly with temperature between \(0\,\)K and \(1000\,\)K.
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first principles modeling of the temperature dependence for the superlattice Intrinsic Stacking Fault energies in l1 _ ni _ 75 x 75 xx _x xal _ 5 5 alloys
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2018Co-Authors: Joshua Allen, Alessandro Mottura, A BreidiAbstract:Stronger and more resistant alloys are required in order to increase the performance and efficiency of jet engines and gas turbines. This will eventually require planar Faults engineering, or a complete understanding of the effects of composition and temperature on the various planar Faults that arise as a result of shearing of the \(\gamma ^\prime \) precipitates. In the current study, a combined scheme consisting of the density functional theory, the quasi-harmonic Debye model, and the axial Ising model, in conjunction with a quasistatic approach is used to assess the effects of composition and temperature of a series of pseudo-binary alloys based on the \(({\mathrm{Ni}}_{75-x}{\mathrm{X}}_{x}){\mathrm{Al}}_{25}\) system using distinct relaxation schemes to assess observed differences. Our calculations reveal that the (111) superlattice Intrinsic Stacking Fault energies in these systems decline modestly with temperature between \(0\,\)K and \(1000\,\)K.
-
first principles modeling of superlattice Intrinsic Stacking Fault energies in ni3al based alloys
Acta Materialia, 2018Co-Authors: A Breidi, Joshua Allen, Alessandro MotturaAbstract:Abstract High-throughput quantum mechanics based simulations have been carried out to establish the change in lattice parameter and superlattice Intrinsic Stacking Fault (SISF) formation energies in Ni3Al-based alloys using the axial Ising model. We had direct access to the variation in SISF energies due to finite compositional change of the added ternary transition metal (TM) element through constructing large supercells, which was equally necessary to account for chemical disorder. We find that most added TM ternaries induce an important quasi-linear increase in the SISF energy as a function of alloying composition x. The most pronounced increase corresponds to Fe addition, while Co addition decreases the SISF energy monotonically. Our results shed light on the role played by TM elements on strengthening L12 Ni3Al precipitates against Stacking Fault shear. The data are of high importance for designing new Ni-based superalloys based on computational approaches.
