It has been widely accepted that the ratio of fatigue limit to tensile strength (for a given test stress ratio) is relatively constant. Recently, however, a correlation was shown between the rotating bending fatigue limit and the true stress-true strain parameters of steels. This paper extends the correlation to axial load fatigue tests of low- and medium-strength steels. Error analysis shows that fatigue limits may be estimated with acceptable precision for strain-hardening exponents greater than 0.1.

"Correlation of Fatigue Limit with True Stress - True Strain Behavior,"
*Materials Research and Standards*, v. 7, no. 9, September 1967, pp
390-392.