Time-Dependent Internal Friction in Deformed Alkali Halide Crystals

抄録

Time-dependent properties of the strain amplitude dependent internal friction in alkali halide crystals were systematically investigated. The measurement technique more reliable than the conventional one was established, and repeatable enhancement and recovery of the internal friction due to external excitation was discovered.
A new procedure for the Granato-Lücke plot was derived from recovery of the internal friction. At the same time, this procedure itself shows validity of the Granato-Lücke theory. The enhancement and recovery was interpreted in terms of the diffusion process of pinning elements during breakaway and the counter-diffusion process of pinning elements during resting of the dislocation-motion. The nature of hysteresis phenomena in internal friction measurements in NaCl crystals was also interpreted by the same mechanism.