Full-field Strain Measurements for Microstructurally Small Fatigue Crack Propagation Using Digital Image Correlation Method

Evgenii Malitckii*, Heikki Remes, Pauli Lehto, Sven Bossuyt

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

2 Citations (Scopus)
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A novel measurement approach is used to reveal the cumulative deformation field at a sub-grain level and to study the influence of microstructure on the growth of microstructurally small fatigue cracks. The proposed strain field analysis methodology is based on the use of a unique pattering technique with a characteristic speckle size of approximately 10 µm. The developed methodology is applied to study the small fatigue crack behavior in body centered cubic (bcc) Fe-Cr ferritic stainless steel with a relatively large grain size allowing a high spatial measurement accuracy at the sub-grain level. This methodology allows the measurement of small fatigue crack growth retardation events and associated intermittent shear strain localization zones ahead of the crack tip. In addition, this can be correlated with the grain orientation and size. Thus, the developed methodology can provide a deeper fundamental understanding of the small fatigue crack growth behavior, required for the development of robust theoretical models for the small fatigue crack propagation in polycrystalline materials.

Original languageEnglish
Article number59134
Number of pages9
JournalJournal of Visualized Experiments
Issue number143
Publication statusPublished - 16 Jan 2019
MoE publication typeA1 Journal article-refereed


  • Engineering
  • Issue 143
  • Digital image correlation
  • small fatigue crack
  • crack growth rate retardation
  • sub grain level
  • shear strain localization
  • strain inhomogeneity
  • Strain inhomogeneity
  • Shear strain localization
  • Small fatigue crack
  • Crack growth rate retardation
  • Sub grain level


Microstructure-based Continuum Damage Modelling of Fatigue in High-performance Welds

Sarikka, T., Malitckii, E., Lehto, P., Åman, M., Remes, H., Gallo, P. & Liinalampi, S.


Project: Academy of Finland: Other research funding

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