A new hybrid stretch forming and double-layer two-point incremental sheet forming process

Zhao, Xuelei; Ou, Hengan

Abstract

This research presents a new hybrid stretch forming and double-layer two-point incremental sheet forming
(hybrid stretch forming and DL-TPIF). The novelty of the proposed hybrid process is first to employ double-layer
blank sheets in the conventional two-point incremental sheet forming (TPIF) process, which allows the material
in the flange region to flow into the deformation region for achieving more uniform thickness distribution and
less thinning. The use of an upper dummy sheet prevents the forming tool from direct contact the target blank
sheet to improve the surface quality. Secondly, the combination of the stretch forming and the DL-TPIF processes
enables seamless integration of the two forming processes to take advantages of both processes. The proposed
new hybrid process was evaluated by two case studies through experimental testing and finite element (FE)
simulation. Three pre-stretching conditions were examined to evaluate the effect of the prior stretching operation. The results showed that the maximum thickness reduction of the dome shape produced by the new stretch
forming and DL-TPIF process was less than one third of that obtained from the conventional TPIF process. The
geometrical accuracy and surface quality were also improved by using this new hybrid forming process.

Citation

Zhao, X., & Ou, H. (2024). A new hybrid stretch forming and double-layer two-point incremental sheet forming process. Journal of Materials Research and Technology, 30, 3485-3509. https://doi.org/10.1016/j.jmrt.2024.04.093

• Journal Article Type: Article
• Acceptance Date: Apr 11, 2024
• Online Publication Date: Apr 12, 2024
• Publication Date: May 1, 2024
• Deposit Date: Apr 24, 2024
• Publicly Available Date: May 9, 2024
• Journal: Journal of Materials Research and Technology
• Print ISSN: 2238-7854
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 30
• Pages: 3485-3509
• DOI: https://doi.org/10.1016/j.jmrt.2024.04.093
• Keywords: Incremental sheet forming, Stretch forming, Hybrid forming, Sheet thinning, Geometrical accuracy
• Public URL: https://nottingham-repository.worktribe.com/output/34103695
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S2238785424008676?via%3Dihub