NASA Bulletin Recommends Homogenization for Aluminum 2219 to Prevent Corrosion and Strength Loss

NASA’s latest Technical Bulletin (TB 26‑07) warns that improper casting and forging of aluminum alloy 2219 can create microstructural defects—disparate grain sizes, copper‑rich intermetallics, and macrosegregation—that reduce ductility, strength and increase corrosion susceptibility. The bulletin recommends a homogenization step after conventional direct‑chill casting, citing studies that use 535 °C for 10 hours to redistribute copper atoms and dissolve residual phases. Following homogenization, multi‑directional deformation (upset forging at 510 °C and warm rolling at 240 °C) further refines grain size and Al₂Cu particle distribution, yielding superior mechanical properties. Verification of the homogenization process is advised through micrographs, DSC or XRD measurements. These measures are critical for aerospace components such as launch vehicle tanks and ISS modules, where material integrity is paramount.