Stress Corrosion Characteristics of AlCuLi AA 2090 Alloy

Abstract

The stress corrosion (SC) characteristics of Al-2.7%Cu-2.2%Li AA(1) 2090 alloy are reviewed with specific reference to results on smooth and precracked specimens exposed to laboratory (3 1/2% NaCl) and marine atmosphere environments, in the underaged condition, the alloy is susceptible to SC cracking in both the “easy path, ” short-transverse direction and the more tortuous long-transverse orientation. Resistance improves significantly upon aging to near peak-strength conditions, with the long-transverse orientation being virtually immune. Underaged material is also susceptible to intergranular and intersubgranular corrosion; attack in the near peak-aged condition is of a pit fissuring nature. Attempts are made to reconcile smooth and precracked specimen results and to explain SC response to aging on the basis of microstructural features.