Atom probe microscopy investigation of Mg site occupancy within delta ' precipitates in an Al-Mg-Li alloy.

B. Gault (1) , X.Y. Cui , M.P. Moody , F. de Geuser (2, 3) , C. Sigli (2) , S.P. Ringer , A. Deschamps (2)

1 GPM - Groupe de physique des matériaux
2 SIMaP - Science et Ingénierie des Matériaux et Procédés
3 Dept. of Mat. Engn, ARC Ctr Excellence Design Light Met,

The composition and site occupancy of Mg within ordered delta ' precipitates in a model Al-Mg-Li alloy have been characterized by atom probe microscopy and first-principles simulations. The concentration in the precipitates is found to be almost the same as that of the matrix; however, we show evidence that Mg partitions to the sites normally occupied by Li in the Ll(2) structure. Density functional calculations demonstrate that this partitioning is energetically favorable, in agreement with experimental results.

Domaines: Matériaux

B. Gault, X.Y. Cui, M.P. Moody, F. de Geuser, C. Sigli, et al.. Atom probe microscopy investigation of Mg site occupancy within delta ' precipitates in an Al-Mg-Li alloy.. Scripta Materialia, 2012, 66 (11), pp.903-906. ⟨10.1016/j.scriptamat.2012.02.021⟩. ⟨hal-00728142⟩