High-Strain-Rate Superplastic Forging of Aluminum Alloys--Materials Modification, Inc., 2929 P-1 Eskridge Road, Fairfax, VA 22031-2213; 703-560-1371
Dr. R. Radhakrishnan, Principal Investigator
Dr. T.S. Sudarshan, Business Official
DOE Grant No. DE-FG02-99ER82825
Amount: $750,000

Currently, superplastic forging is limited to low strain rates (10^-5-10^-3s^-1) and to the forming of aerospace components. It is limited by the high cost associated with thermomechanical and recrystallization processes, and the long time ($ 30 minutes) required to form near-net shapes. This project will demonstrate an economical synthesis and processing technique for Al-Cr-Fe alloys and superplastically form them to near-net shape. The superplastic behavior of these alloys will be studied and used to design and fabricate near-net shape parts in a short cycle time (<10 min). The Phase I project synthesized nano-crystalline aluminum, chromium, and iron nanopowders. These nanopowders were alloyed using high-energy ball milling and super-plastically forged in less than 10 minutes. In Phase II, nanocrystalline Al-Cr-Fe alloys will be synthesized directly. Fundamental understanding of the effect of powder particle characteristics (particle size, size distribution and morphology) on the consolidation and superplastic forming of these alloys will be evaluated. These data will be used to fabricate fuselage fairings, pulley sprockets and rocker arms.

Commercial Applications and Other Benefits as described by the awardee: High-strain-rate superplastic forging is expected to result in economically-viable, rapid near-net-shape forming technique for the automobile, aerospace, and semiconductor industries.