The suggestion (attachment) from Manohar Sehgal is covering low to high cycle fatigue data on smooth and notch samples in bending fatigue (as far as I can read from his attachment). Please be aware that fatigue S-N curves data for low-medium carbon steels are dependent on:
- test method (bending, axial..). The data given by Manohar is only valid for bending with given notch factors/smooth specimen data. Axial S-N curves will be different.
- Severity of the notch (e.g. notch sensitivity/stress concentration).
- Load frequency (usually lower level of the S-N curves at lower
frequencies due to the influence of corrosion fatigue).
- Ambient air humidity. High humidity combined with lower frequencies give lower S-N curves. If the notch is relatively sharp, the negative effects of low load frequency and high humidity can give un-normal data because the S-N curves are dominated by Stage II crack growth and adjoining crack closure..
- load ratio (R- ratio)!!!
- Processing condition of the actual steel, e,g. what temper condition, what microstructure and grain sizes, what inclusion size distribution level, etc.