The unique hybrid precipitate in a peak-aged Al-Cu-Mg-Ag alloy. (15th March 2021)

• Record Type: Journal Article
• Authors: Gazizov, M.R.; Boev, A.O.; Marioara, C.D.; Andersen, S.J.; Holmestad, R.; Kaibyshev, R.O.; Aksyonov, D.A.; Krasnikov, V.S.
• Is Part Of: Scripta materialia. Number 194(2021)
• Publication Date: 2021-03-15
• Subjects: Aging -- Scanning/transmission electron microscopy (STEM) -- Aluminum alloys -- Precipitation -- Density functional theory (DFT); Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2020.113669
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: The prevalent hardening phase forming in an Al-Cu-Mg-Ag alloy after peak-aging at 150 and 190 °C has been investigated using transmission electron microscopy methods. The precipitate atomic structure was determined. It is a hybrid precipitate (HP) with plate morphology on {111}Al planes, consisting of orthorhombic and hexagonal structural fragments. Density functional theory calculations suggest that the hybridization reduces structural incompatibility of the HP plates with the Al matrix at the broad interfacial boundaries. Incorporation of Cu, Mg and Ag in the bulk HP structure reduces its formation enthalpy.