Zener Relaxation in Al-Li Binary Alloys
نویسنده
چکیده
Internal friction (I.F.) and modulus measurements have been carried out as a function of temperature in order to study the Li mobility in an A1 8.1 at% Li 0.03 at% Zr alloy. The results show that the sequence of 6' and 6 precipitation can be followed through the evolution of the internal friction spectra. Two peaks appear in the internal friction spectrum. The low temperature peak Pz (450 K), has associated a dynamic modulus defect, an activation energy of 1.2 eV and the width of a Debye peak. The analysis of the behaviour of this relaxation allows us to identify the Pz peak with the Zener relaxation process. The relaxation parameters lead us to determine the activation energy and the diffusion coefficient of Li in Aluminium.
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