Effect of load ratio on the deformation behaviour of fatigue crack tips

M. Shimojo, M. Chujo, Y. Higo, S. Nunomura

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


To investigate the change in the manner of plastic deformation at a fatigue crack tip under different loading conditions, the fresh surface area which is produced in one fatigue cycle at the crack tip was measured by an electrochemical method under various load ratios. The fresh surface area produced in each fatigue cycle is in proportion to the crack propagation rate in the Paris regime. This indicates that the crack tip geometry at Kmax maintains a similar profile through the Paris regime. Furthermore, the fresh surface area is independent of load ratio at a given da/dN in the Paris regime. This suggests that the shape of the fatigue crack tip at Kmax should be independent of load ratio at a given da/dN, and that the shape at Kmin is also independent of load ratio, whereas the size of the deformed region at the crack tip is in proportion to da/dN.

Original languageEnglish
Pages (from-to)455-459
Number of pages5
JournalInternational Journal of Fatigue
Issue number6
Publication statusPublished - 1993 Nov
Externally publishedYes


  • fresh surface
  • load ratio
  • polarization current
  • propagation model

ASJC Scopus subject areas

  • Modelling and Simulation
  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering
  • Industrial and Manufacturing Engineering


Dive into the research topics of 'Effect of load ratio on the deformation behaviour of fatigue crack tips'. Together they form a unique fingerprint.

Cite this