Difference between generalized and localized cracking

[victorzv]

The question may be stupid, but I cannot find any clear definition of both generalized and localized cracking.

Does anybody know the difference, preferably in aircraft structures?
Thank you.

 

[rb1957]

localised cracking is an isolated crack, say a crack at a hole. typically initiated by a specific (individual) flaw.

generalised cracking is several cracks reasonably close together, or multi-site damage. typically initiated by fatiguing many small (minor) flaws that are replicated at many sites (ie typical manufacturing quality).

 

[victorzv]

Thank you rb1957!

May I say that cracks found in a joint or fitting (where we have significant load transfer from fastener to fastener) are localized, while cracks found at a wing skin panel spanwise splice (load transfer is almost zero) are generalized in terms of the wing fatigue life?

Or you think my interpretation is irrelevant?

 

[rb1957]

i wouldn't connect the terms with load transfer. splices with load transfer are just as likely to develop generalised fatigue cracking as those without load transfer.