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Formulation of Failure Strain according to Average Stress Triaxiality of Low Temperature High Strength Steel (EH36)

저온용 고장력강(EH36)의 평균 응력 삼축비에 따른 파단 변형률 정식화

  • Received : 2013.01.18
  • Accepted : 2013.04.19
  • Published : 2013.04.30

Abstract

Stress triaxiality is recognized as one of the most important factors for predicting the failure strain of ductile metals. This study dealt with the effect of the average stress triaxiality on the failure strain of a typical low-temperature high-strength marine structural steel, EH36. Tensile tests were carried out on flat specimens with different notches, from relatively smooth to very sharp levels. Numerical simulations of each specimen were performed by using ABAQUS. The failure initiation points in numerical simulations were identified from a comparison of the engineering stress vs. strain curves obtained from experiments with simulated ones. The failure strain curves for various dimensionless critical energy levels were established in the average stress triaxiality domain and compared with the identified failure strain points. It was observed that most of the failure initiation points were approximated with a 100% dimensionless critical energy curve. It was concluded that the failure strains were well expressed as a function of the average stress triaxiality.

Keywords

Average stress triaxiality;Equivalent plastic strain;Failure strain;Average true stress

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Cited by

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  2. Development of Three Dimensional Fracture Strain Surface in Average Stress Triaxiaility and Average Normalized Lode Parameter Domain for Arctic High Tensile Steel: Part I Theoretical Background and Experimental Studies vol.29, pp.6, 2015, https://doi.org/10.5574/KSOE.2015.29.6.445
  3. Development of Three-Dimensional Fracture Strain Surface in Average Stress Triaxiaility and Average Normalized Lode Parameter Domain for Arctic High Tensile Steel: Part II Formulation of Fracture Strain Surface vol.29, pp.6, 2015, https://doi.org/10.5574/KSOE.2015.29.6.454
  4. Punching Fracture Simulations of Circular Unstiffened Steel Plates using Three-dimensional Fracture Surface vol.30, pp.6, 2016, https://doi.org/10.5574/KSOE.2016.30.6.474
  5. Ductile Fracture Predictions of High Strength Steel (EH36) using Linear and Non-Linear Damage Evolution Models vol.31, pp.4, 2017, https://doi.org/10.26748/KSOE.2017.08.31.4.288

Acknowledgement

Supported by : 한국연구재단