Abstract
Incremental sheet forming (ISF) is a new promising manufacturing technology with high potential to shape complex three-dimensional parts by using a relative small tool. However, ISF is presently limited due to non-uniform thickness distribution of formed parts, especially excessive thinning on severely sloped regions. This typically leads to fracture and hence limits process formability. This paper aims to tackle this issue by developing appropriate tool path strategies for multi-pass deformation design in ISF. More specifically, two more complex shapes are designed to validate the proposed multi-pass deformation design methodology by finite element simulations and experiments. The interactions of different tool path strategies on material thinning of the final part are evaluated in terms of process formability and thickness strain distribution given the same multi-pass design. Furthermore, the movement of material points is traced to explain the material flow mechanism in multi-pass forming compared to single-pass forming. It is concluded that both deformation passes (intermediate shapes) and tool path generation strategies would influence the thickness strain distribution as well as process formability. Appropriate tool paths should be devised to further reduce material thinning and improve the process formability by taking the geometrical features of the designed part into account. Additionally, the proposed multi-pass deformation design enables sufficient material to flow into the deformed region from the outside region so as to allow a compressive deformation state to develop and steeper shapes to be formed.
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References
Jeswiet J, Micari F, Hirt G, Bramley A, Duflou JR, Allwood JM (2005) Asymmetric single point incremental forming of sheet metal. CIRP Ann Manuf Technol 54(2):623–650
Emmens WC, Sebastiani G, van den Boogaard AH (2010) The technology of incremental sheet forming—a brief review of the history. J Mater Process Technol 210(8):981–997
Kim TJ, Yang DY (2000) Improvement of formability for the incremental sheet metal forming process. Int J Mech Sci 42(7):1271–1286
Young D, Jeswiet J (2004) Wall thickness variations in single-point incremental forming. Proc IMechE Part B: J Eng Manuf 218(11):1453–1459
Duflou JR, Verbert J, Belkassem B, Gu J, Sol H, Henrard C, Habraken AM (2008) Process window enhancement for single point incremental forming through multi-step toolpaths. CIRP Ann Manuf Technol 57(1):253–256
Skjoedt M, Silva MB, Martins PAF, Bay N (2010) Strategies and limits in multi-stage single-point incremental forming. J Strain Anal Eng 45(1):33–44
Cui Z, Gao L (2010) Studies on hole-flanging process using multistage incremental forming. CIRP J Manufact Sci Tech 2(2):124–128
Manco L, Filice L, Ambrogio G (2011) Analysis of the thickness distribution varying tool trajectory in single-point incremental forming. Proc IMechE Part B: J Eng Manuf 225(3):348–356
Malhotra R, Bhattacharya A, Kumar A, Reddy NV, Cao J (2011) A new methodology for multi-pass single point incremental forming with mixed toolpaths. CIRP Ann Manuf Technol 60(1):323–326
Xu DK, Malhotra R, Reddy NV, Chen J, Cao J (2012) Analytical prediction of stepped feature generation in multi-pass single point incremental forming. J Manuf Process 14(4):487–494
Li JC, Hu JB, Pan JJ, Geng P (2012) Thickness distribution and design of a multi-stage process for sheet metal incremental forming. Int J Adv Manuf Technol 62(9–12):981–988
Li JC, Shen JJ, Wang B (2013) A multipass incremental sheet forming strategy of a car taillight bracket. Int J Adv Manuf Technol 69(9–12):2229–2236
Liu ZB, Li YL, Meehan PA (2013) Vertical wall formation and material flow control for incremental sheet forming by revisiting multistage deformation path strategies. Mater Manuf Processes 28(5):562–571
Liu ZB, Daniel WJT, Li YL, Liu S, Meehan PA (2014) Multi-pass deformation design for incremental sheet forming: analytical modeling, finite element analysis and experimental validation. J Mater Process Technol 214(3):620–634
Rauch M, Hascoet JY, Hamann JC, Plenel Y (2009) Tool path programming optimization for incremental sheet forming applications. Compu Aided Design 41(12):877–885
Liu ZB, Li YL, Meehan PA (2013) Experimental investigation of mechanical properties, formability and force measurement for AA7075-O aluminum alloy sheets formed by incremental forming. Int J Precis Eng Manuf 14(11):1891–1899
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Appendix (drawings for asymmetric free-form shape)
Appendix (drawings for asymmetric free-form shape)
It is noted that the asymmetric free-form shape is obtained by shifting the center point 1 of the hemispherical shape in a symmetric part to the center point 2 of the hemispherical shape in the asymmetric free-form shape (for detailed dimensions, refer to Fig. 15 below).
Drawings for asymmetric free-form shape (unit: mm). a Front view. b Left view
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Liu, Z., Li, Y. & Meehan, P.A. Tool path strategies and deformation analysis in multi-pass incremental sheet forming process. Int J Adv Manuf Technol 75, 395–409 (2014). https://doi.org/10.1007/s00170-014-6143-6
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DOI: https://doi.org/10.1007/s00170-014-6143-6