Master Curve for the Fatigue Strength at Zero Stress Ratio

5 Master Curve for the Fatigue Strength at Zero Stress Ratio 

To describe the master curve for (Tj.q, we need the reduced frequency/ in addition to the reduced time r/, each defined by 

We introduce two alternative expressions for the master curve for zero stress ratio Of o(/f /, T and (Tf oitf, Nf, T. In the latter expression, the explicit reference to frequency is suppressed in favor of Nf. Equation (4) enables one to construct the master curve from the tests at a single frequency and various temperatures. 

---