Ag precipitation and dissolution reactions in the Cu–3 wt.% Al–4 wt.% Ag alloy

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2006-12, Vol.441 (1), p.259-265
• Main Authors: Adorno, A.T., Silva, R.A.G., Neves, T.B.
• Format: Article
• Language: English
• Subjects: Cross-disciplinary physics: materials science; rheology; Dissolution reaction; Exact sciences and technology; Hardness; Materials science; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Precipitation; Precipitation reaction; Thermal analysis
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.08.055

The Ag precipitation and dissolution reactions in the Cu–3 wt.% Al–4 wt.% Ag alloy were studied using isothermal and non-isothermal analyses. The activation energy values, obtained for the Ag precipitation reaction indicated that, when the Kissinger, Ozawa and Johnson–Mehl–Avrami methods are compared, the Kissinger method is the most appropriate. Although the Johnson–Mehl–Avrami equation often does not fit precipitation data, the n values obtained for Ag precipitation kinetics are in agreement with what was experimentally observed. For the dissolution reaction of Ag precipitates the activation energy values obtained from the Kissinger and Ozawa methods are higher than that found in the literature for the Ag dissolution in Cu. This discrepancy seems to be related to the fact that the activation energy is influenced by the heating rate.