Corrosion Properties of Spacelab Structural Alloy Aluminum 2219-T851

摘要

The corrosion protection systems and wrought alloy selected for Spacelab 2219 applications were subjected to surface corrosion and stress corrosion salt spray tests or immersion in 3.5% sodium chloride solution. Results demonstrate that all chemically oxidized surfaces must be finished with space approved paints to avoid corrosion. Anodized finishes are expected to survive the Spacelab 10 year life requirement. Forged ring, rolled plate and welded plate (TIG, electron beam and repaired) 2219-T851 passes standard stress corrosion tests. Samples were stressed in the short transverse direction, at 75% of the 0.2% proof stress, for at least 30 days. The alloy BS L 93 (equivalent to AA 2024) was simultaneously tested and failed the ESA stress corrosion requirements.