Evaluation of Protruding Head, Overaged Rivets

Abstract

Overaged 7075-T6 aluminum alloy rivets were sdught as replacement for 2024-T31 aluminum rivets which presented production,,difficulties. Heat treatment of 7075-0 aluminum alloy rivets by means of a 30-minute 870°F solution heat treatment, followed by water quenching and aging for 4-1/2 hours at 3250F provided 7075-T6 rivets which were 10 per dent stronger than 2024-T31 rivets, and were comparable with the 2024-T31 rivets with respect to driving characteristicS. Salt spray tests of 500 hours duration with rivets stressed to 4o,'50, 6d and 68 per cent of their ultimate tensile strength did not indicate incidence of stress corroston cracking. The solution potential of the 7075-T6 was not changed by the revised heat treatment.