Size effect in gas forming a hot-bent AA5xxx V-shaped trough trimmed for an airplane strakelet skin panel

• Published in: International journal of advanced manufacturing technology 2016-10, Vol.86 (9-12), p.2747-2752
• Main Authors: Lee, Shyong, Tang, Jung-Sung, Chu, Chun-Lin
• Format: Article
• Language: English
• Subjects: CAE) and Design; Computer-Aided Engineering (CAD; Contours; Engineering; Industrial and Production Engineering; Mechanical Engineering; Media Management; Metal sheets; Original Article; Plastic buckling; Shape; Size effects; Superplastic forming; Superplasticity; Thickness; Wings (aircraft)
• ISSN: 0268-3768; 1433-3015
• DOI: 10.1007/s00170-016-8380-3

Superplastic forming or gas forming is favorable method for the manufacture of sheet metal for making airplane skin panels. However, a major challenge in applying this method is controlling the thickness distribution in the formed product. Here, we explore a hot-bending-assisted process for gas forming of a deep trough with a complex shape for use in airplane wings. We propose the deliberate arrangement of wrinkles to achieve uniform thickness distribution. Because full-scale experiments are costly, sub-scale specimens are preferred for collecting experimental data. In linking sub-scale data to full-scale manufacturing, the size effect on wrinkle formation sites is important. The cause of the pre-form contour and larger-size specimen could be the greater variations in contour modes due to plastic buckling during the pre-forming stage.