金属の弾性異方性と回折ヤング率比の関係

抄録

Elastic anisotropy of polycrystalline metals can be evaluated by the difference in diffraction Young's modulus of each crystal plane {hkl} and the values of Young's modulus are theoretically calculated applying the stiffness; C₁₁, C₁₂ and C₄₄ to the Reuss and Voigt model. In this paper, the values of diffraction Young's modulus E^*_hkl are calculated by the Reuss-Voigt average model for pure iron (bcc), austenitic steels (fcc), nickel (fcc), copper (fcc) and aluminum (fcc) and then the Young's modulus ratio ω_hkl=(E^*_hkl/E₀) is proposed to evaluate the relative elastic anisotropy. Here, E₀ denotes the value obtained by the Voigt model. The value of E₀ can be estimated from the experimentally obtained Young's modulus E_m for polycrystalline metals by the equation; E₀≒1.13E_m. It was also found that there is good correlation between the anisotropy parameter A_i (=2C₄₄/(C₁₁-C₁₂)) and ω_h00=(E^*_h00/E₀).