Constraint Effect on the Ductile Fracture Behavior of High-Strength Pipeline Steels

Abstract:

This work presents an investigation of the ductile tearing properties for a pipe with internal and external circumferential cracks using 2D plane strain and axisymmetric models. Crack growth resistance curves were computed using the complete Gurson model. The pipes with various crack depths and internal pressures were analyzed. The results were compared with those of corresponding SENT and SENB specimens. It clearly indicated a significant effect of constraint on the resistance curves for internal and external cracked pipes. A minor effect of hoop stress induced by internal pressure on the CTOD-resistance curves is expected for deep-cracked pipes. The SENT specimen is a better representation of circumferentially flawed pipes and an alternative to the conventional standard SENB specimen for the fracture mechanics testing in engineering critical assessment of high-strength pipeline steels.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 899-904
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.899
• Online since: March 2016
• Authors: Jie Xu*, Xiao Min Zhuo, Peng Peng Li, Yu Fan, Zhi Sun
• Keywords: Crack Growth Resistance Curve, Crack Tip Constraint, Finite Element Analysis, High Strength Pipeline Steels, Large Scale Yielding

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