Development of a Stretch Forming Process for 2055 Al Li Fuselage Frames

The use of formed and machined extrusions for integral aircraft fuselage frames allows for reduced part count, improved assembly, and weight savings when compared to legacy sheet metal designs. To determine the viability of using new aluminum alloys for fuselage frames, Gulfstream Aerospace has researched several high strength extrusion alloys, including aluminum lithium alloys. Early efforts with aluminum lithium alloys led to inconsistent properties, severe recrystallization, and extensive orange peel. Gulfstream and Arconic were able to overcome these obstacles using a newly developed temper for 2055 aluminum extrusions. This presentation will step through the different trials performed and discuss the results throughout each stage of the trials.