Natural aging on Al-Cu-Mg structural hardening alloys - Investigation of two historical duralumins for aeronautics

Audrey Cochard (1) , Kailin Zhu (2, 3) , Sébastien Joulié (4) , Joël Douin (5) , Julitte Huez (3, 2) , Luc Robbiola (6) , Philippe Sciau (1) , Magali Brunet (1)

1 CEMES-M3 - Matériaux Multi-fonctionnels et Multi-échelles
2 ENSIACET - Ecole nationale supérieure des ingénieurs en arts chimiques et technologiques
3 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
4 CEMES - Centre d'élaboration de matériaux et d'études structurales
5 CEMES-PPM - Physique de la Plasticité et Métallurgie
6 TRACES - Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés

This article presents the metallurgic study of sixty years old structural hardening Al-Cu-Mg alloys recovered from a double-deck aircraft Breguet 765. This study aims to characterize and understand the evolution of alloys over very long periods thanks to an approach coupling materials characterization and archives researches. The focus is made on two ancient age hardening Al-Cu alloys: A-U4G and A-U4G1, whose compositions are close to the international designations 2017A and 2024 respectively. Multi-scale structural investigation was carry out and mechanical properties were extracted. It is shown that despite natural aging during long periods, these alloys exhibit mechanical properties (yield strength, ultimate tensile strength and rupture strain) close to the expected original specifications.

Mots clés: Electron microscopy; Mechanical characterization; Precipitation; Aging; Aluminum alloys

Domaines: Matériaux

Audrey Cochard, Kailin Zhu, Sébastien Joulié, Joël Douin, Julitte Huez, et al.. Natural aging on Al-Cu-Mg structural hardening alloys - Investigation of two historical duralumins for aeronautics. Materials Science and Engineering: A, 2017, 690, pp.259-269. ⟨10.1016/j.msea.2017.03.003⟩. ⟨hal-01485289⟩