Gas forming of shallow rounded rectangular pan using aluminum alloy sheets

Hydroforming involves the use of a pressurized fluid to form complex and/or intricate component shapes and includes three currently available manufacturing techniques—superplastic forming (SPF), quick plastic forming (QPF), and gas forming, which however, is seldom used. This gas-forming technique involving the use of gas pressure along with four different die-entrance geometries to form a shallow rounded rectangular pan—having a width-to-depth ratio of approximately 10—from aluminum alloy sheets has been explored and reported. The relevant experimental process is appropriately described and analyzed along with associated failure patterns observed in specimens. Adoption of a two-stage forming process involving preform production is proposed to address the problem associated with die-entrance contours. Lastly, the procedure concerning selection of an optimum Al alloy conducive for use in the gas-forming process has been explained. The gas-forming technique discussed herein is well-suited for use in mass production of metallic cases for smartphones. In addition to achieving the desired contour, other crucial criteria, such as production rate, product surface quality, and dimensional precision, need to be addressed through further research. © 2018, Springer-Verlag London Ltd., part of Springer Nature.