Retrogression and reaging response of 7475 aluminium alloy

Abstract

AbstractAbstractThe age-hardening response of 7475 aluminium alloy has been investigated at 110°, 120°, 1400 , and 160°C, using yield-strength and electrical-conductivity measurements. Heat-treatment parameters were established to give a T6-type starting condition for specimens which were further processed by retrogression and reaging (RRA). The RRA-processed materials were further characterized by yield-strength, electrical-conductivity, and stress-corrosion-crack growth-rate measurements. The results indicate that stress-corrosion-crack growth rates can be varied independently of yield strength, and T6 strength levels can be achieved in materials having stress-corrosion resistance comparable to that of the T73 condition for alloy 7475.