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Comparative Study on Crack Tip Opening Displacment ${\delta}_5$ R-Curve and ${\delta}_{BS}$ R-Curve

균열선단 열림변위 {\delta}_5 R-곡선과 {\delta}_{BS} R-곡선의 비교연구

Kim, Eom-Gi;Nam, Seung-Hun;Jin, Uk;Go, Seong-Wi
김엄기;남승훈;진욱;고성위

  • Published : 2000.03.01

Abstract

Since the examination of CTOD problem revealed that the discrepancy among CTOD's was a matte., of definition, the relationships among parameters based on different definitions have been studied Particularly, the relationship between $\sigma$BS R-curve based on BS 7448 and R-curve based on the recently introduced $\sigma$5 parameter was investigated in this research. For the comparison, compact tension specimens of used 1Cr-0.5Mo steel, heat treated 1Cr-0.5Mo steel to mimic the new one, A12024-T6, and A12024-T351 were prepared and tested. Consequently, the relationship between $\sigma$5 and $\sigma$BS R-curves for tested materials were established by shifting the rotational center which could determined by rotation factor and ligament size.

Keywords

CTOD;R-Curve;BS 7448;J Integral;DC Potential Drop Method

References

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