Al - 2.5wt% Li 합금의 시효특성에 미치는 Mg 첨가효과

Abstract

The effects of Mg addition on the aging characteristics of Al-2.5wt%Li alloys have been studied using transmission electron microscopy and differential scanning calorimetry. Results of lattice parameter measurement suggested that the Mg atoms tend to dissolve in the δ` particles. The coarsening of δ` particles generally obeys the LSW kinetics and its rate constant appears not to be much affected by the Mg addition. The kinetics of the precipitation of b phase could be best described by a kinetic law of Avrami type with n=1.5. The addition of 1wt% Mg results in a decrease of the activation energy for the formation of the 8 phase from 141KJ/mole to 137KJ/mole.