[en] The conception of the Jules Horowitz Reactor (JHR) requires to qualify at high neutron fluences the alloys which will be used for the tank, the core components and the experimental devices. To validate the choice of an aluminum alloy for the JHR tank, we started an extensive characterization program of Al-alloys irradiated in research reactors during at least 15 years. For this program, we investigated some highly irradiated materials: the AG3-NET in annealed condition (5754-NET-O) and the 6061-T6. The 5754-NET-O is coming from components replaced during the refurbishment of the OSIRIS and ORPHEE reactors operated by CEA at Saclay (France). The components are the lattice structure of OSIRIS, the cold source shell of ORPHEE and the irradiation tube I1 of ORPHEE, which were respectively irradiated for 30 years (from 1966 to 1996), 15 years (from 1980 to 1995) and 21 years (from 1980 to 2001). The 6061-T6 alloy is extracted from rods used as beryllium plug during 32 years in the BR2 reactor located at Mol (Belgium). This paper describes the mechanical tests (tension, fracture toughness) already performed on these materials. The effect of neutron fluence on the mechanical properties of the AG3-NET-O (5754-NET-O) and 6061-T6 alloys is investigated. Finally, an outline of the further program for the qualification of the JHR tank and experimental devices is provided for both alloys. (author)