Nonhydrostatic compression of elastically anisotropic polycrystals. II. Direct compression and plastic deformation

Article

关键词: CALIBRATION;   

DOI  :  10.1103/PhysRevB.57.3264

来源: SCIE

【 摘 要 】

The effects of nonhydrostatic conditions on the compression behavior of elastically anisotropic polycrystals have been studied by energy-dispersive x-ray diffraction of a foil of Cu3Au compressed directly between diamond anvils. A volume expansion between 0.3 and 1 Cpa is explained to result from the introduction of dislocations. A volume incompressibility accompanied by saturation in stress, strain, and the stacking fault probability between 1 and 2 GPa is due to work hardening. A complete pressure cycle, including repressurization after pressure release, and the compression of Cu3Au previously deformed by filing demonstrate that mutual repulsion between lattice defects also contributes to the volume incompressibility. The pressure region of incompressibility terminates at a discontinuity which occurs when the yield strength of the plastically deformed material is exceeded. The compression above this point is elastic and isotropic. The yield strength is estimated from the offset of the measured compression curves from the hydrostat.

【 授权许可】

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