Skip to main content
SpringerLink
Log in

Influence of microstructure on the mechanical properties and the forming behaviour of very thin metal foils

  • SPECIAL ISSUE - ORIGINAL ARTICLE
  • Published:
The International Journal of Advanced Manufacturing Technology Aims and scope Submit manuscript

Abstract

The demand for accurate process design of microforming processes is increasing steadily due to ongoing miniaturisation. Occurring size effects, however, prevent the transfer of existing know-how of standard sheet forming processes with conventional dimensions like blanking, bending and deep drawing on microforming processes. These size effects are either generally valid for all microforming processes, as the influence of the share of surface grains are process-specific, like the influence of large strain gradients as they appear, e.g. in bending processes. A decisive parameter for the occurrence of size effects is the ratio of material mean grain size to foil thickness. For a simulation-based description of microforming processes, the implementation of size-dependent material behaviour in finite element (FE) simulation is essential. Hence, a reliable determination of size-dependent mechanical properties as input data for FE simulation is needed to provide a broad fundamental database for a future theoretical description of microforming processes. In the present paper, the influence of the material microstructure on the mechanical properties of metal foils with thicknesses ranging from 25 to 500 μm is discussed based on tensile tests, bulge tests and fundamental bending experiments. Challenges resulting from the small thickness of the metal foils are pointed out, and future demands regarding determination of material characteristics of thin metal foils are presented.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Kals TA, Eckstein R (2000) Miniaturization in sheet metal working. J Mater Process Technol 103:95–101. doi:10.1016/S0924-0136(00)00391-5

    Article  Google Scholar 

  2. Raulea LV, Goijaerts AM, Govaert LE, Baaijens FPT (2001) Size effects in the processing of thin metal sheets. J Mater Process Technol 115:44–48. doi:10.1016/S0924-0136(01)00770-1

    Article  Google Scholar 

  3. Banks D, Wilcox A (2000) Microsystems technology—new opportunities in metal forming. In: Shirvani B et al (eds) Sheet metal 2000, April 17–19, University of C. England, pp 281–290

  4. Engel U (2004) Tribology in microforming. Proceedings of the 2nd International Conference on Tribology in Manufacturing Processes ICTMP. Nyborg, Dänemark, 15.06.–18.06.2004, vol. 2, pp 549–560

  5. Tiesler N, Engel U, Geiger M (1999) Forming of microparts—effects of miniaturization on friction. In: Geiger M (ed) Advanced technology of plasticity. Proceedings of the 6th ICTP, 19–24 Sep 1999, vol II. Nuremberg, Germany. Springer, Berlin, pp 889–894

  6. Kals RTA (1999) Fundamentals on the miniaturization of sheet metal working processes. Meisenbach, Bamberg

    Google Scholar 

  7. Cavaliere P, Gabrielli F, Fratini L (2000) Bending of very thin sheets: the influence of thickness on material characterisation. In: Pietrzyk (ed) Metal forming 2000. A.A. Balkema, Rotterdam, The Netherlands, pp 405–410

    Google Scholar 

  8. Kocańda A, Prejs T (2000) The effect of miniaturisation on the final geometry of the bent products. In: Pietrzyk (ed) Metal forming 2000. A.A. Balkema, Rotterdam, The Netherlands, pp 375–378

    Google Scholar 

  9. Fleck NA, Hutchinson JW (1997) Strain gradient plasticity. Adv Appl Mech 33:295–361

    Article  Google Scholar 

  10. Ashby MF (1970) The deformation of plastically non-homogeneous materials. Philos Mag 21:399–424. doi:10.1080/14786437008238426

    Article  Google Scholar 

  11. Nye JF (1953) Some geometrical relations in dislocated crystals. Acta Metall 1:153–162. doi:10.1016/0001-6160(53)90054-6

    Article  Google Scholar 

  12. Geißdörfer S, Engel U, Geiger M (2006) FE-simulation of microforming processes applying a mesoscopic model. Int J Mach Tools Manuf 46:1222–1226

    Google Scholar 

  13. Picart P, Michel JF (1999) Effects of size and texture on the constitutive behaviour for very small components in sheet metal forming. In: Geiger M (ed) Advanced technology of plasticity. Proceedings of the 6th ICTP, 19–24 Sep 1999, vol II, Nuremberg, Germany. Springer, Berlin, pp 895–900

  14. Mahabunphachai S, Koç M (2007) Investigation of size effects on material behaviour of thin sheet metals in hydraulic bulge testing and micro-channel hydroforming. Proceedings of the 2nd International Conference on Micromanufacturing. Clemson University Greenville, USA, pp 145–149

  15. Hoffmann H, Hong S (2006) Tensile test of very thin sheet metal and determination of flow stress considering the scaling effect. Ann CIRP 55(1):263–266

    Article  Google Scholar 

  16. Hašek VV (1978) Untersuchung und theoretische Beschreibung wichtiger Einflußgrößen auf das Grenzformänderungsschaubild. Teil 1–3. Blech Rohre Profile 25:213–220 285–292, 493–499

    Google Scholar 

  17. Gologranc F (1975) Beitrag zur Ermittlung von Fließkurven im kontinuierlichen hydraulischen Tiefungsversuch. Dissertation (PhD thesis), Institute for Metal Forming Technology, University of Stuttgart, Germany

Download references

Author information

Authors and Affiliations

  1. Chair of Manufacturing Technology, University of Erlangen-Nuremberg, Egerlandstr. 13, 91058, Erlangen, Germany

    A. Diehl, U. Engel & M. Geiger

Authors
  1. A. Diehl
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. U. Engel
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. M. Geiger
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to A. Diehl.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Diehl, A., Engel, U. & Geiger, M. Influence of microstructure on the mechanical properties and the forming behaviour of very thin metal foils. Int J Adv Manuf Technol 47, 53–61 (2010). https://doi.org/10.1007/s00170-008-1851-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00170-008-1851-4

Keywords

Search

Navigation