Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Measurement of Micro-Tensile Properties using ESPI technique

ESPI 기법을 이용한 미소 인장 특성 추정

  • Published : 2001.05.01
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Abstract

An electronic speckle pattern interferometry (ESPI) system for measuring tensile properties under micro-tensile testing has been developed. The system consists of an optical system and an image processing system. In the optical system, optical components for measurement of in-plane deformation are arranged on the path of He-Ne laser. In the image processing system, the window-based program for acquiring speckle pattern interferometric image was developed and deformation in a small specimen is continuously evaluated during the test. Using this system, tensile strain of copper foil was measured during tensile testing. Tensile specimen had the thickness and width of 22 and 500 ${\mu}{\textrm}{m}$, respectively. Tensile properties, including the elastic modulus, yielding strength and tensile strength, of the copper were evaluated and also plastic exponent and coefficient in the Ramberg-Osgood relationship were evaluated from the stress-strain curve.

Keywords

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