Eleventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids
J. Phys. IV France 06 (1996) C8-325-C8-328
Ratio of Decrement to Modulus Change for Amplitude-Dependent Internal FrictionA.B. Lebedev1, 2
1 Department of Physics, University of Illinois, 1110 West Green St., Urbana, IL 61801, U.S.A.
2 Solid State Physics Division, A.F. Ioffe Physico-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg, Russia.
The ratio r of the amplitude-dependent decrement δh to the amplitude-dependent modulus defect ΔM/M has been analyzed within the framework of theories of dislocation hysteresis based on both the breakaway Granato-Lücke model and the symmetrical pointed loop frictional model. In the particular case of power laws with the same exponent n for both the decrement and modulus defect : δh=r(ΔM/M)α σon, analytical expressions for the relationship between r and n have been derived. The theoretical requirements have been compared with the available experimental data. The use of r for identifying the mechanism of dislocation hysteresis is demonstrated.
© EDP Sciences 1996