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Thomas Böhlke - One of the best experts on this subject based on the ideXlab platform.

  • Asymptotic values of Elastic Anisotropy in polycrystalline copper for uniaxial tension and compression
    Computational Materials Science, 2003
    Co-Authors: Thomas Böhlke, Albrecht Bertram
    Abstract:

    The asymptotic values of Elastic Anisotropy, induced in OFHC copper by uniaxial tension and compression, are determined by a phenomenological model and compared with the predictions of Taylor type texture simulations. The evolution equation for the texture-dependent anisotropic part of the effective Elasticity tensor consists of two parts. The first term depends only on inElastic rate of deformation and represents the driving term for the evolving Anisotropy. The second term governs the saturation of Anisotropy and is linear in the anisotropic portion of the effective Elasticity tensor. In the present paper it is shown that such an evolution equation implies a reasonable prediction of the asymptotic Elastic Anisotropy for uniaxial tension and uniaxial compression.

  • Simulation of texture induced Elastic Anisotropy of polycrystalline copper
    Computational Materials Science, 1999
    Co-Authors: Albrecht Bertram, Thomas Böhlke
    Abstract:

    Abstract The texture induced Elastic Anisotropy of polycrystalline copper is studied for different finite deformation paths. As a homogenization technique, the Taylor–Lin model is used, which is a first-order theory and incorporates only a volume-fraction representation of microstructure. In order to identify the Anisotropy of the macroscopic Elastic behaviour, approximations of the macroscopic strain energy density corresponding to different symmetry groups are determined and compared.

Albrecht Bertram - One of the best experts on this subject based on the ideXlab platform.

  • Asymptotic values of Elastic Anisotropy in polycrystalline copper for uniaxial tension and compression
    Computational Materials Science, 2003
    Co-Authors: Thomas Böhlke, Albrecht Bertram
    Abstract:

    The asymptotic values of Elastic Anisotropy, induced in OFHC copper by uniaxial tension and compression, are determined by a phenomenological model and compared with the predictions of Taylor type texture simulations. The evolution equation for the texture-dependent anisotropic part of the effective Elasticity tensor consists of two parts. The first term depends only on inElastic rate of deformation and represents the driving term for the evolving Anisotropy. The second term governs the saturation of Anisotropy and is linear in the anisotropic portion of the effective Elasticity tensor. In the present paper it is shown that such an evolution equation implies a reasonable prediction of the asymptotic Elastic Anisotropy for uniaxial tension and uniaxial compression.

  • Simulation of texture induced Elastic Anisotropy of polycrystalline copper
    Computational Materials Science, 1999
    Co-Authors: Albrecht Bertram, Thomas Böhlke
    Abstract:

    Abstract The texture induced Elastic Anisotropy of polycrystalline copper is studied for different finite deformation paths. As a homogenization technique, the Taylor–Lin model is used, which is a first-order theory and incorporates only a volume-fraction representation of microstructure. In order to identify the Anisotropy of the macroscopic Elastic behaviour, approximations of the macroscopic strain energy density corresponding to different symmetry groups are determined and compared.

Kenneth E. Evans - One of the best experts on this subject based on the ideXlab platform.

  • Elastic Anisotropy and extreme Poisson's ratios in single crystals
    Acta Materialia, 2010
    Co-Authors: Zoe A. D. Lethbridge, Richard I. Walton, Arnaud Marmier, Christopher W. Smith, Kenneth E. Evans
    Abstract:

    Abstract The relationship between Elastic Anisotropy and extreme Poisson’s ratio behaviour (either positive or negative) in single-crystalline materials has been investigated using experimentally determined single-crystal Elastic constants for a wide range of solid materials. This makes use of a recently proposed Elastic Anisotropy index that is applicable to all crystal symmetries. For many real materials we find a striking correlation between the value of the Elastic Anisotropy index and the magnitudes of maximum and minimum Poisson’s ratios this is independent of crystal symmetry. This structure–property relationship provides new examples of auxetics and shows that negative Poisson’s ratios are actually not uncommon among many classes of inorganic (and organic) materials, including elemental metals, alloys, ionic solids, molecular solids and giant covalent networks.

Junqin Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Stability, Elastic Anisotropy, and electronic properties of Ca 2 C 3
    Chinese Physics B, 2017
    Co-Authors: Quan Zhang, Qun Wei, Haiyan Yan, Xuanmin Zhu, Junqin Zhang, Xiao-fei Jia, Ronghui Yao
    Abstract:

    The systematic investigations of the mechanical, Elastic, and electronic properties, and stability of the newly synthesized monoclinic C2/m-Ca2C3 are performed, based on the first-principles calculations. Ca2C3 is found to be mechanically and dynamically stable only from 0 GPa to 24 GPa. The Elastic Anisotropy studies show that Ca2C3 exhibits the Elastic Anisotropy increasing with the augment of pressure. Furthermore, using the HSE06 hybrid functional, the electronic properties of Ca2C3 under pressure are calculated. The structure can be regarded as a quasi-direct band gap semiconductor, and the pressure-induced direct-indirect band gap transition is studied in detail.

  • Elastic Anisotropy and thermodynamic properties of superhard c-C3N under pressure
    Diamond and Related Materials, 2017
    Co-Authors: Quan Zhang, Qun Wei, Haiyan Yan, Xuanmin Zhu, Xiaofeng Shi, Junqin Zhang
    Abstract:

    Abstract An investigation of the Elastic Anisotropy and the thermodynamic property of a recently reported novel superhard material c-C3N was made in this work. The calculated shear modulus, Poisson's ratio and Young's modulus increase with pressure and exhibit Elastic Anisotropy. Furthermore, the moduli at different pressures have the similar Anisotropy. The pressure and temperature dependences of the Debye temperature, Gruneisen parameter, thermal expansion, and heat capacity were studied systematically by using the quasi-harmonic Debye model. The pressure and temperature in the calculation were varied in the range of 0–100 GPa and 0–2000 K, respectively. The Debye temperature varies from 1563 K to 2495 K under the given conditions. The Gruneisen parameter varies from 1.383 to 2.213, and almost keeps constant at low temperatures (T

H.r. Gong - One of the best experts on this subject based on the ideXlab platform.

  • Structural stability, mechanical property and Elastic Anisotropy of TiAl-H system
    International Journal of Hydrogen Energy, 2012
    Co-Authors: S. Chen, Chaoping Liang, H.r. Gong
    Abstract:

    First-principles calculation reveals that the Ti100−xAlx-H phases with hydrogen at octahedral(O) interstitial sites are energetically more favorable than corresponding tetrahedral(T) interstitial sites, and that the O and T sites become thermodynamically stable with negative heats of formation when x is less than about 57 and 38, respectively. Calculation also shows that H has an important effect on mechanical properties of TiAl-H phases, and that the TiAl-H phases with H at O sites are more brittle with bigger Elastic moduli than corresponding T sites. In addition, three anisotropic indexes are used to express the Elastic Anisotropy of various TiAl and TiAl-H phases, and the changes of Elastic Anisotropy are discussed in terms of electronic structures. The calculated results are compared with available experimental results in the literature and the agreements between them are fairly good.