It is quite unknown that Paris law constants are not real material constants. This can be clearly seen from the generalized Kitagawa diagram which represents the size effect (the effect of initial sizes of cracks) as function of fatigue life. This note gives a very short but precise introduction to the problem, and some references.
Conference Paper A largely unknown problem in fatigue crack propagation data
Anyone has experience on this problem? Is interested to discuss? Has Paris law constants for cracks of very different sizes? Please get in touch!
regards, MC
Hi Michele,
Short fatigue cracks was a favourite topic of Professor Keith Miller who was based in Sheffield University (UK).
You might find that the following eulogy is interesting.
https://www.esis.site/docs/council/Council2006/Kfouri.pdf
Regards,
Simon
Hi Michele,
One of your figures shows an axis with cracks as short as 10^-6m. That seems short to me.
Regards,
Simon