The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Chongyu Wang - One of the best experts on this subject based on the ideXlab platform.
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Alloying Element dependence of structural elastic and electronic properties of nickel based superalloys influence of γ volume fraction
Journal of Alloys and Compounds, 2020Co-Authors: Chongyu WangAbstract:Abstract First-principles calculations are carried out to investigate the structural, elastic, and electronic properties of nickel-based model superalloys. The effects of Alloying Element X (where X = Hf, Ta, Mo, W, Cr, Re, Ru, or Co) on the mechanical characteristics of Ni/Ni3Al ternary multilayer structures are obtained and discussed. The γ ’ -volume-fraction dependence of mechanical performance is studied in detail for the first time and the calculated elastic parameters are in good agreement with experimental results at room temperature. The influence of Alloying Elements on bulk modulus is almost independent of γ ’ volume fraction. While the effects of Alloying Elements on shear modulus, Young’s modulus, the ductile and brittle behavior, some particular orientation-dependent elastic moduli and Zener anisotropy factor are closely related to γ ’ volume fraction. Alloying additions increase the Young’s and shear moduli, reduce the ductility and lower the anisotropy performance, but the degree of influence on these properties varies with γ ’ volume fraction. Among the three γ ’ volume fractions investigated in this work, nickel-based ternary model superalloys with 60% γ ’ volume fraction have significant improvement in Young’s and shear moduli and thus possess the best comprehensive elastic performance. Furthermore, covalent-like bonding between Alloying dopants and host atoms and strong X d- Ni d hybridization account for the superior elastic properties of superalloys with Alloying additions. Alloying dopants and Ni atoms from the interface and two phases share a DOS peak just below the Fermi level, and this additional d-d hybridization leads to the exceptional mechanical performance of superalloys with 60% γ’ volume fraction.
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influence of the Alloying Element re on the ideal tensile and shear strength of γ ni3al
Scripta Materialia, 2009Co-Authors: Yunjiang Wang, Chongyu WangAbstract:The effects of the Alloying Element Re on the ideal strength of gamma'-Ni(3)Al under tensile and shear stresses are investigated using the first-principles method. Results for the stress-strain relationships, ideal tensile and shear strengthes with and without Re addition are presented and explained. Re is found to be effective in improving the strength of Ni(3)Al. The electronic mechanism underlying the strengthening effects of Re is also elucidated. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Yong Du - One of the best experts on this subject based on the ideXlab platform.
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effects of Alloying Element and temperature on the stacking fault energies of dilute ni base superalloys
Journal of Physics: Condensed Matter, 2012Co-Authors: Shunli Shang, Chelsey L Zacherl, H Z Fang, Yi Wang, Yong DuAbstract:A systematic study of stacking fault energy (?SF) resulting from induced alias shear deformation has been performed by means of first-principles calculations for dilute Ni-base superalloys (Ni23X and Ni71X) for various Alloying Elements (X) as a function of temperature. Twenty-six Alloying Elements are considered, i.e.,?Al, Co, Cr, Cu, Fe, Hf, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Sc, Si, Ta, Tc, Ti, V, W, Y, Zn, and Zr. The temperature dependence of ?SF is computed using the proposed quasistatic approach based on a predicted ?SF?volume?temperature relationship. Besides ?SF, equilibrium volume and the normalized stacking fault energy (?SF?=??SF/Gb, with G the shear modulus and b the Burgers vector) are also studied as a function of temperature for the 26 Alloying Elements. The following conclusions are obtained: all Alloying Elements X studied herein decrease the ?SF of fcc Ni, approximately the further the Alloying Element X is from Ni on the periodic table, the larger the decrease of ?SF for the dilute Ni?X alloy, and roughly the ?SF of Ni?X decreases with increasing equilibrium volume. In addition, the values of ?SF for all Ni?X systems decrease with increasing temperature (except for Ni?Cr at higher Cr content), and the largest decrease is observed for pure Ni. Similar to the case of the shear modulus, the variation of ?SF for Ni?X systems due to various Alloying Elements is traceable from the distribution of (magnetization) charge density: the spherical distribution of charge density around a Ni atom, especially a smaller sphere, results in a lower value of ?SF due to the facility of redistribution of charges. Computed stacking fault energies and the related properties are in favorable accord with available experimental and theoretical data.
Shunli Shang - One of the best experts on this subject based on the ideXlab platform.
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effects of Alloying Element and temperature on the stacking fault energies of dilute ni base superalloys
Journal of Physics: Condensed Matter, 2012Co-Authors: Shunli Shang, Chelsey L Zacherl, H Z Fang, Yi Wang, Yong DuAbstract:A systematic study of stacking fault energy (?SF) resulting from induced alias shear deformation has been performed by means of first-principles calculations for dilute Ni-base superalloys (Ni23X and Ni71X) for various Alloying Elements (X) as a function of temperature. Twenty-six Alloying Elements are considered, i.e.,?Al, Co, Cr, Cu, Fe, Hf, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Sc, Si, Ta, Tc, Ti, V, W, Y, Zn, and Zr. The temperature dependence of ?SF is computed using the proposed quasistatic approach based on a predicted ?SF?volume?temperature relationship. Besides ?SF, equilibrium volume and the normalized stacking fault energy (?SF?=??SF/Gb, with G the shear modulus and b the Burgers vector) are also studied as a function of temperature for the 26 Alloying Elements. The following conclusions are obtained: all Alloying Elements X studied herein decrease the ?SF of fcc Ni, approximately the further the Alloying Element X is from Ni on the periodic table, the larger the decrease of ?SF for the dilute Ni?X alloy, and roughly the ?SF of Ni?X decreases with increasing equilibrium volume. In addition, the values of ?SF for all Ni?X systems decrease with increasing temperature (except for Ni?Cr at higher Cr content), and the largest decrease is observed for pure Ni. Similar to the case of the shear modulus, the variation of ?SF for Ni?X systems due to various Alloying Elements is traceable from the distribution of (magnetization) charge density: the spherical distribution of charge density around a Ni atom, especially a smaller sphere, results in a lower value of ?SF due to the facility of redistribution of charges. Computed stacking fault energies and the related properties are in favorable accord with available experimental and theoretical data.
Krzysztof J. Kurzydlowski - One of the best experts on this subject based on the ideXlab platform.
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Ab initio calculations of the generalized stacking fault energy in aluminium alloys
Scripta Materialia, 2011Co-Authors: M. Muzyk, Zbigniew Pakiela, Krzysztof J. KurzydlowskiAbstract:The generalized stacking fault energy for aluminium and some of its alloys have been calculated using density functional theory. It is shown that the deformation tendency caused by emission of partial dislocations varies with Alloying Element. The twinnability of aluminium is also modified by the presence of Alloying Element in the deformation plane. The results suggest that Al-Mg and Al-Ga alloys are the most susceptible for the deformation by partial dislocations and twining. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Chelsey L Zacherl - One of the best experts on this subject based on the ideXlab platform.
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effects of Alloying Element and temperature on the stacking fault energies of dilute ni base superalloys
Journal of Physics: Condensed Matter, 2012Co-Authors: Shunli Shang, Chelsey L Zacherl, H Z Fang, Yi Wang, Yong DuAbstract:A systematic study of stacking fault energy (?SF) resulting from induced alias shear deformation has been performed by means of first-principles calculations for dilute Ni-base superalloys (Ni23X and Ni71X) for various Alloying Elements (X) as a function of temperature. Twenty-six Alloying Elements are considered, i.e.,?Al, Co, Cr, Cu, Fe, Hf, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Sc, Si, Ta, Tc, Ti, V, W, Y, Zn, and Zr. The temperature dependence of ?SF is computed using the proposed quasistatic approach based on a predicted ?SF?volume?temperature relationship. Besides ?SF, equilibrium volume and the normalized stacking fault energy (?SF?=??SF/Gb, with G the shear modulus and b the Burgers vector) are also studied as a function of temperature for the 26 Alloying Elements. The following conclusions are obtained: all Alloying Elements X studied herein decrease the ?SF of fcc Ni, approximately the further the Alloying Element X is from Ni on the periodic table, the larger the decrease of ?SF for the dilute Ni?X alloy, and roughly the ?SF of Ni?X decreases with increasing equilibrium volume. In addition, the values of ?SF for all Ni?X systems decrease with increasing temperature (except for Ni?Cr at higher Cr content), and the largest decrease is observed for pure Ni. Similar to the case of the shear modulus, the variation of ?SF for Ni?X systems due to various Alloying Elements is traceable from the distribution of (magnetization) charge density: the spherical distribution of charge density around a Ni atom, especially a smaller sphere, results in a lower value of ?SF due to the facility of redistribution of charges. Computed stacking fault energies and the related properties are in favorable accord with available experimental and theoretical data.
