ELECTROCHEMICAL INVESTIGATION OF INTERDIFFUSION IN AL + LI ALLOYS

The interdiffusion coefficients in Al plus Li alloys are measured by the use of transient techniques such as chronopotentiometry and chronoamperometry. The imposed pulses are both anodic and cathodic under galvanostatic and potentiostatic conditions. Taking into account the charging of the double layer, the adsorption of the diffusing species, and the movement of the electrode/electrolyte interface, the diffusion coefficients of Li in the Al plus Li alloys ( alpha -phase and beta -phase) are determined at 422 degree C to be a function of the composition X mol Li percent. The surface composition of the alloys is estimated from a polynomial expression. The present results are in good agreement with those reported in the literature and obtained by other methods.