Learning Forum

[mehmetyaylaciinfo]

Hi,

I have done high cycle fatigue analysis (S-N Time Series) and obtained 4392 cycles. Should I do low cycle fatigue analysis (E-N Time Series) again?

[danielshaw]

Probably.  SN is only valid for high-cycle fatigue (HF) using elastic stresses.  A predicted fatigue life for a ductile metal of only 4392 cycles is probably indicating low-cycle fatigue (LCF) produced by plastic strains.  The predicted life of 4392 cycles is probably conservative, but if you want a more accurate life prediction, you should use EN.

[mehmetyaylaciinfo]

Yes, this analysis for Al7075-T6 and conservative. Certainty of survival is 95% 

Thank you so much for answer