Control and relief of residual stresses in high-strength aluminum alloy parts for aerospace industry

Residual stresses of a very significant level were introduced when aluminum alloy parts were quenched in cold water from the temperature of solution treatment Residual stresses cause not only distortion and cracking, but also enhance susceptibility to stress corrosion cracking (SCC) and lead to premature failure The aim of this research is how to control and relieve residual stresses in high-strength aluminum alloy parts First, various quenching processes have been evaluated in an attempt to combine low residual stresses with the required levels of mechanical properties during solid solution, involving quenching into boiling water, spray quenching and polymer glycol quenchants The second part of this paper is focused on the comparison of different stress-relieving techniques, highlighting their key attributes, specific advantages and limitations Moreover, the paper concludes that all stress-relieving techniques should be carried out immediately after being quenched in the solution treatment.