Stress Corrosion Testing of a Superplastically Deformed Aluminum-Lithium Alloy

An investigation was conducted to study the stress corrosion cracking (SCC) tendency of a superplastically deformed aluminum-lithium-based alloy (AA X2094 [UNS A92094]) that had been received in a thermomechanically processed form suitable for dynamic recrystallization. Tensile specimens made from sheets of this material were superplastically deformed at a constant true strain rate of 2 x 10⁻⁴ /s and a temperature of ~ 500°C. Specimens then were subjected to stress corrosion testing using the slow strain rate tensile testing (SSRT) technique at a constant initial strain rate of 2 x 10⁻⁶ /s. Effects of different superplastic deformation variables and stress corrosion testing conditions on the stress-strain relationship of the test specimens were studied.