Experimental Mechanics

, Volume 41, Issue 1, pp 58–62 | Cite as

Electronic speckle pattern interferometry analysis of tensile tests of semihard copper sheets

  • C. Vial-Edwards
  • I. Lira
  • A. Martinez
  • M. Münzenmayer
Article

Abstract

Uniaxial tension tests of semihard copper sheets were studied by means of electronic spekle pattern interferometry (ESPI). The setup allowed the authors to analyze in detail the transitions from elastic to plastic behavior and from homogeneous to inhomogeneous plastic deformation. In agreement with the conventional definition of the yield point for copper fully plastic behavior starded at permanent strains close to 0.005. The strain-hardening coefficient was very low at the early stage of plastic flow (“easy glide”), increasing progressively until values on the order of 0.13 to 0.14 were reached at maximum load. A this point, the appearance of unequally spaced fringes signaled the beginning of inhomogeneous deformation. With ESPI, this occurrence may thus serve as a criterion to establish the forming limit of the material.

Key Words

Electronic speckle pattern interferometry (ESPI) tensile tests semihard copper sheets 

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Copyright information

© Society for Experimental Mechanics, Inc. 2001

Authors and Affiliations

  • C. Vial-Edwards
    • 1
  • I. Lira
    • 1
  • A. Martinez
    • 1
  • M. Münzenmayer
    • 1
  1. 1.Escuela de IngenieriaPontificia Universidad Católica de ChileSantiagoChile

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