Creep crack growth characterization of SS316LN

ABSTRACT

In creep conditions, conventionally, C* and C(t) line integrals are used for characterising the crack tip. However, the true crack driving force or its rate cannot be described by any of the conventional parameters. The theoretical validity of conventional crack tip-characterising parameters like J or Ct is also restricted, making it hard to anticipate the driving forces underlying cracks. To investigate the creep crack growth behaviour of this material an experimental analysis of SS316LN at 650 °C is performed. The crack extension is modelled through the node-release technique, and a configurational force-based rate of change of J integral is calculated by post-processing of the finite element results. The results show that the Ct and dJepc/dt calculated from FE analyses are similar and the trend is also similar to the experimentally measured C*-values.

KEYWORDS:

• Creep crack growth (CCG)
• configurational forces (CF)
• node release technique
• crack driving forces

Acknowledgments

The authors acknowledge the Science and Research Board (SERB) for funding for the work under project SRG/2021/000523 titled “Application of configurational force based concept of material inhomogeneity to enhance crack resistance of materials”, Indian Institute of Technology Ropar for the infrastructural support and Metallurgy and Material Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu 603 102, India for experimental support.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Indian Institute of Technology Ropar Science and Engineering Research Board [SRG/2021/000523].