Measurement of Tensile Properties Dependent on the Small-Scaled Specimen Dimension for Evaluation of In-Service Materials Properties

사용재 물성 평가를 위한 미소 시험편 크기에 따른 인장 특성 평가

  • Huh, Yong-Hak (Division of Metrology for Quality Life, Korea Research Institute of Standards and Science) ;
  • Kim, Dong-Iei (Division of Metrology for Quality Life, Korea Research Institute of Standards and Science) ;
  • Kim, Dong-Jin (Division of Metrology for Quality Life, Korea Research Institute of Standards and Science) ;
  • Lee, Hae-Moo (Division of Metrology for Quality Life, Korea Research Institute of Standards and Science) ;
  • Park, Jong-Seo (Division of Metrology for Quality Life, Korea Research Institute of Standards and Science)
  • 허용학 (한국표준과학연구원 삶의질표준부 에너지인프라연구단) ;
  • 김동일 (한국표준과학연구원 삶의질표준부 에너지인프라연구단) ;
  • 김동진 (한국표준과학연구원 삶의질표준부 에너지인프라연구단) ;
  • 이해무 (한국표준과학연구원 삶의질표준부 에너지인프라연구단) ;
  • 박종서 (한국표준과학연구원 삶의질표준부 에너지인프라연구단)
  • Published : 2008.10.31

Abstract

To evaluate the mechanical properties of in-service materials, tensile properties measurement using small-scaled specimen has been carried out. Tensile testing specimens with various dimensions, including standard and sub-size specimen specified in ASTM and ISO and small-scaled specimen, were prepared. Tensile strain in small-scaled specimen was measured using micro-ESPI system set up in this study. This system was used in the specimen with the parallel length of 2 mm and in subsequently measuring the strain under tensile loading. From each type of tensile specimen, stress-strain curves were determined. The dimension effect of the tensile properties was investigated comparing the tensile results obtained from standard specimens and small-scaled specimens. It was shown that the tensile strength for the small-scaled specimen is lower by 15% than those for the standard specimen.

Keywords

References

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