Prediction of the strength of aged Al-Cu alloys with non-hybrid and hybrid {100}Al plates

• Published in: Computational materials science Vol. 207; p. 111331
• Main Authors: Krasnikov, V.S., Gazizov, M.R., Mayer, A.E., Bezborodova, P.A., Pogorelko, V.V., Kaibyshev, R.O.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-05-2022
• Subjects: Aluminum alloy; Dislocation; Molecular dynamics; Precipitate; Scanning/transmission electron microscopy (STEM); Molecular dynamics; Scanning/transmission electron microscopy (STEM); Precipitate; Dislocation; Aluminum alloy
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2022.111331

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The effect of precipitate hybridization on macroscopic strengthening in aluminum alloys is investigated on the example of Al-Cu alloy using multiscale approach combining molecular dynamics (MD), continuum modeling and discrete dislocation dynamics (DDD). Non-hybrid and hybrid {100}Al plates are considered to involve θ′-phase and θ′-phase in the core and Guinier-Preston zone (GP-like) structure along the broad interfaces, respectively. MD simulations evidence a complex dislocation-precipitate interaction mechanism involving bypassing of both hybrid and non-hybrid {100}Al plates by dislocations at early deformation stages and their shearing by the following dislocations. MD results are used to calibrate a continuum model of dislocation-precipitate interactions in 2D DDD. The shear strength of alloy with hybrid precipitates is found to be 20% higher than that for non-hybrid plates at the same Cu content exceeding 2 wt%.