Fracture Forming Limits for Near Net Shape Forming of Sheet Metals

  • J. P. Magrinho
  • M. B. SilvaEmail author
  • P. A. F. Martins
Part of the Materials Forming, Machining and Tribology book series (MFMT)


The continuous innovations in sheet metallic materials lead to the need of the development of new and innovative forming methodologies. The emergence of the near net shape technologies, with the aim to create a product as close as possible to the final component, is an answer to these recent progresses. The knowledge of the formability limits of a material, that define the capacity of a material to deform permanently without failure (by necking or fracture) allows a better design of a near net shape manufacturing process. This chapter describes the methodology to determine experimentally the fracture limits by tension (fracture forming limit line—FFL) and in-plane shear (shear fracture forming limit line—SFFL). For this, commonly utilized laboratory test specimens for mechanical, fracture and formability characterization are used to determine gauge length strains at the post-testing cracked regions of the specimen and involves the determination of the gauge length strains at the cracked regions of the specimens.


Forming limit diagram Fracture Plasticity Engineering materials 



The authors acknowledge the provided support by Fundação para a Ciência e a Tecnologia of Portugal and IDMEC under LAETA-UID/EMS/50022/2013, PDTC/EMS-TEC/0626/2014 and the support by the project MODSEAT.: Modular Light-Rail Seat, P2020 LISBOA-01-0247-FEDER-017247.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • J. P. Magrinho
    • 1
  • M. B. Silva
    • 1
    Email author
  • P. A. F. Martins
    • 1
  1. 1.IDMEC, Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

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