Measurement of Tensile Properties of Copper Foil using Micro-ESPI Technique

마이크로 ESPI기법을 이용한 동 박막의 인장 특성 측정

  • 김동일 (전남대학교 기계공학과 대학원) ;
  • 허용학 (한국표준과학연구원 강도평가그) ;
  • 기창두 (전남대학교 기계시스템공학부)
  • Published : 2004.08.01

Abstract

Micro-tensile testing system, consisting of a micro tensile loading system and micro-ESPI(Electronic Speckle Pattern Interferometry) system, has been developed for measurement of micro-tensile properties of thin micro-materials. Micro-tensile loading system had a load cell with the maximum capacity of 50N and micro actuator with resolution of 4.5nm in stroke. The system was used to apply a tensile load to the micro-sized specimen. During tensile loading, the micro-ESPI system acquired interferornetric speckle patterns in the deformed specimen and measured the in-plane tensile strain. The ESPI system consisted of a CCD-camera with a lens and the window-based program developed for this experiment. Using this system, stress-strain curves for 4 kinds of electrolytic copper foil 18$\square$m thick were obtained. From these curves, tensile properties, including the elastic modulus. yielding strength and tensile strength, were determined and also values of the plastic exponent and coefficient based on Ramberg-Osgood relationship were evaluated.

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