Retrogression, reaging and residual stresses in 7010 forgings

Abstract

ABSTRACTOpen die forgings of the aluminium alloy 7010 (DTD5636) have been retrogressed at temperatures between 200 and 240 °C and then reaged (RRA). Tensile, fracture toughness and stress corrosion cracking values are reported. Retrogression at 200 °C offers the most promising combination of properties, and the long retrogression time of approx. 2500 s will enable thick sections to be treated. Residual stresses induced during quenching are also predicted, and initial experimental results suggest that some stress relief occurs during the retrogression heat treatment.