ICIFUAS 11
Eleventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids

J. Phys. IV France 06 (1996) C8-85-C8-88
DOI: 10.1051/jp4:1996816

Anomalous Behaviour of the Zener Relaxation in Cu-Au

F. Povolo^{1, 2, 3} and E.B. Hermida<sup>1, 2, 3

1</sup>  Departamento de Física, Fac. de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón I, Ciudad Universitaria, 1428 Buenos Aires, Argentina
²  Unidad de Actividad Materiales, Comisión Nacional de Energía Atómica, Av. del Libertador 8250, 1429 Buenos Aires, Argentina
³  Consejo Nacional de investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina

Abstract
Measurements of the Zener relaxation in single crystals of Cu-18at.%Au and Cu₃Au are presented. In the 18at.% alloy only one internal friction peak is observed at low frequencies (of the order of 1 Hz). This peak is only slightly wider than a Debye's peak. An additional hump appears at intermediate frequencies (of the order of 60 Hz). The Zener peak in the Cu₃Au alloy is accompanied by an additional maximum produced by the order-disorder transition. A measurement of the derivative of the damping with respect to the frequency through the use of a pendulum with variable moment of inertia shows that non-linear effects are present in the Zener relaxation in both alloys.

© EDP Sciences 1996