Numéro
J. Phys. Colloques
Volume 48, Numéro C8, Décembre 1987
Fifth European Conference on Internal Friction and Ultrasonic Attenuation in Solids
Page(s) C8-547 - C8-552
DOI https://doi.org/10.1051/jphyscol:1987886
Fifth European Conference on Internal Friction and Ultrasonic Attenuation in Solids

J. Phys. Colloques 48 (1987) C8-547-C8-552

DOI: 10.1051/jphyscol:1987886

PREMARTENSITIC INTERNAL FRICTION IN INDIUM-THALLIUM ALLOY

I.C. HWANG1, C.Y. LEI1, T. SUZUKI2 et M. WUTTIG3

1  Metallurgy Department, University of Missouri-Rolla, Rolla, MO 65401, U.S.A.
2  Institute of Applied Physics, University of Tsukuba, Sakura, Ibaraki, 305, Japan
3  Engineering Materials Group, Department of Chemical and Nuclear Engineering, University of Maryland, College Park, MD 20742, U.S.A.


Abstract
The internal friction in In-24at%Tl alloy prior to the martensitic transformation has been measured by use of the vibrating reed method in the frequency range up to 500 Hz. The internal friction is found to be described by the Debye relaxation process Q-1=Δτω/ (1+τ2ω2), where the relaxation time τ is controlled by a thermally activated process with an activation energy of 0.78 ev and the relaxation strength Δ behaves according to the Curie-Weiss law 1/(T-TC). A relaxed shift of the X-ray Bragg diffraction peak under the influence of uniaxial stress with the same activation energy has been found in the same alloy system. These experimental data indicates that the relaxation process responsible for the internal friction as well as the diffraction shift is to be associated with extended lattice defects-premartensitic solitons.