Experimental Mechanics

, Volume 31, Issue 4, pp 348–352 | Cite as

Determination of the plastic zone by laser-speckle correlation

  • Y. Z. Dai
  • C. J. Tay
  • F. P. Chiang
Article

Abstract

Laser-speckle-pattern correlation is used for the determination of elastic-plastic boundary on the surface of well polished metal specimens. The method employs a converging laser beam to illuminate the test object. Diffracted verging laser beam to illuminate the test object. Diffracted images are recorded and processed on a computer-based vision system. Subsequent image-correlation analysis yields information on the surface deformation of the test objects. The technique is applied to a flat tensile specimen with two circular notches at the central portion. Measured plastic zone is compared with results obtained by the finite-element method.

Keywords

Mechanical Engineer Laser Beam Fluid Dynamics Vision System Plastic Zone 

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Copyright information

© Society for Experimental Mechanics, Inc. 1991

Authors and Affiliations

  • Y. Z. Dai
    • 1
  • C. J. Tay
    • 2
  • F. P. Chiang
    • 3
  1. 1.Department of Mechanical EngineeringState University of New York at Stony Brook
  2. 2.Department of Mechanical and Production EngineeringNational University of SingaporeSingapore
  3. 3.Mechanical EngineeringState University of New York at Stony Brook

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