Precipitation and Dissolution Kinetics of GP Zones and Metastable Phase in Al-3wt.%Cu Alloy

B. Khamela, b, F. Sahnouneb, c, N. Brihia, M. Fatmi1mm aDepartment of Physics, University Mohamed Seddik Ben Yahia of Jijel, Jijel 18000, Algeria bResearch Unit on Emerging Materials (RUEM), Ferhat Abbas of Setif 01, Setif 19000, Algeria cPhysics Department, Faculty of Science, University Mohamed Boudiaf of M'sila, 28000 M'sila, Algeria

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The kinetic parameters such as activation energy E and the growth morphology parameters n and m were determined by a non-isothermal method. The microstructure variations of the precipitation and dissolution of GP zone and metastable phase θ' in Al-3wt.% Cu were analyzed by optical microscopy and X-ray diffraction. The kinetics of GP zone and metastable phase θ' in Al-3wt.% Cu was investigated using differential thermal analysis between room temperature and 430° at heating rates of 20, 25 and 30°Cmin-1. The activation energies of GP zone precipitation, formation of θ'/θ and dissolution of θ' were 26, 105 and 77 kJmol-1, respectively. The growth morphology parameters n (Avrami parameter which indicates the crystallization mode) and m (a numerical factor which depends on the dimensionality of crystal growth) are both about 1.5.

DOI:10.12693/APhysPolA.134.45 topics: differential thermal analysis (DTA), precipitation, activation energies