A study on the re-solution heat treatment of AA 2618 aluminum alloy

In the present study, the effects of re-solution treatment of AA2618 aluminum alloy has been investigated. Solution heat treatments of 520-640 °C for 14-24 h were applied followed by artificial aging. Characterization studies that were carried out by optical microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy techniques showed that recrystallisation was not observed by solution treatment at 530 °C whereas it did occur as the solution treatment and the duration time were increased above 530 °C. Increasing the solution treatment temperature further coarsened both the grains and the precipitates, resulting in significant reduction in hardness. Al9FeNi-type intermetallics are not completely dissolved by these solution treatments.