Journal de Physique IV

Sommaire

Journées d'Étude des Équilibres entre Phases

J. Phys. IV France 11 (2001) Pr10-127-Pr10-131
DOI: 10.1051/jp4:20011018

Diffusivité du joint de grain durant la précipitation discontinue de solutions solides sursaturées Mg-Al et Mg-Al-Cd

D. Bradai, B. Alili and M. Kadi-Hanifi

Faculté des Sciences (Physiques), USTHB, BP. 32, El-Alia, Dar-El-Beida, Alger, Algeria

Abstract
The grain boundary chemical diffusivity triple product SδD_b parameter ( s being the Gibbs segregation factor, δ the thickness and D_b the chemical diffusivity of the grain boundary) of Al in a binary MgAl and a ternary MgAlCd solid solutions during the discontinuous precipitation reaction have been determined using several analytical models. A comparison of the values obtained with the experimental data and the deduction of the activation energy confirm the reaction to be controlled by diffusion of Al atoms at the migrating grain boundary.