Stability of β″ nano-phases in Al-Mg-Si(-Cu) alloy under high dose ion irradiation. (15th April 2017)

• Record Type: Journal Article
• Authors: Flament, Camille; Ribis, Joël; Garnier, Jérôme; Serruys, Y.; Leprêtre, F.; Gentils, A.; Baumier, C.; Descoins, M.; Mangelinck, D.; Lopez, A.; Colas, K.; Buchanan, K.; Donnadieu, P.; Deschamps, Alexis
• Is Part Of: Acta materialia. Volume 128(2017)
• Page Start: 64
• Page End: 76
• Publication Date: 2017-04-15
• Subjects: Aluminium alloys -- β″ Nano-phases -- Irradiation effect -- Transmission electron microscopy -- Atom-probe tomography; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2017.01.044
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: The microstructure of a 6061-T6 Al alloy subjected to ion irradiation at 95 and 165 displacements per atom (dpa) has been evaluated by transmission electron microscopy and atom-probe tomography. The initial microstructure of the alloy is dominated by needle-shaped β″ precipitates. After 95 dpa irradiation, the β″ precipitates display a slight lattice distortion and are partially dissolved, together with the formation of a new phase. After 165 dpa irradiation, the β″ precipitates are completely dissolved, the new phase has grown and a high density of clusters rich in Mg, Si, Cu and Cr is observed. The determination of ballistic versus radiation enhanced diffusion coefficients shows that enhanced diffusion is predominant for β" dissolution. The formation and growth of the new particles may be caused by radiation induced segregation. Solute drag by vacancies or mixed dumbbell interstitials migration could explain the diffusion of some elements as Si or Cr towards the new particles. Graphical abstract: Image