Effect of aging time and temperature on intergranular corrosion of aluminium alloys

Purpose Two types of aluminium alloys, 2024‐T3 and 7075‐T6, having been selected, this study aims to investigate the effect of metallurgical aspects on intergranular corrosion. Design/methodology/approach To determine and evaluate the metallurgical effects of heat treatments on corrosion behaviour of these alloys, G67 ASTM test was selected. Findings The results showed that with increasing the aging time in aluminium alloy type 2024‐T3 the susceptibility to intergranular corrosion increases, while in type 7075‐T6 with increasing aging time the intergranular corrosion rate remains nearly unchanged. Practical implications As these results refer to precipitate the intermetallic compound phases, the amount of these phases increases with the increase of the aging time in both alloys. Originality/value The investigations showed that the phases that initiate in 2024‐T3 act as anode sites, while in 7075‐T6 they act as cathode sites.