Analytical Computing Stresses and Strains in Single Point Incremental Forming

Abstract:

Nowadays, Single Point Incremental Forming (SPIF) has become popular for metal sheet forming technology in industry in many advanced countries. In the recent decade, many relative studies have concentrated on this new technology of forming sheet by Finite Element Method (FEM) as well as by empirical way. There were very rare studies by pure analytical computing and P.A.F. Martins et al. under a title “Theory of single point incremental forming” performed almost all these researches were based on the analytical framework of SPIF in 2008. After careful studying on this research, we found out its light illogical result: the stresses inside of a random point in the workpiece sheet are constant and not related to the coordinate of the formed point of the sheet. Therefore, it cannot explain the mechanism of rupture and tear of the sheet that is really a serious restriction of the SPIF technology nowadays. This paper dedicates to suggest a new version of pure analytical computing the normal stresses at a random formed point in the sheet that could explain the tear mechanism and a FEM simulation was also carried out also to prove the conviction of the recommended formula.

• Periodical: Key Engineering Materials (Volume 825)
• Pages: 129-139
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.825.129
• Online since: October 2019
• Authors: Le Khanh Dien*, Le Khanh Tan, Van Thanh Nguyen, Huy Bich Nguyen, Thanh Nam Nguyen
• Keywords: Analytical Computing Strains, Analytical Computing Stresses, Incremental Sheet Forming, SPIF

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