Mean Stress and Ratcheting Considerations in Uniaxial Fatigue under Stress Control
The fatigue life data obtained under stress control conditions with and without mean stress are interpreted with reference to mean stress and ratcheting effects. Tests are conducted on nickel-base super-alloy Inconel 718 at 649°C and copper alloy Elbrodur-NIB at room temperature. The ratcheting strains at failure are obtained, and mean stress models such as the modified Goodman equation, the Smith-Watson-Topper parameter, and the Walker parameter are evaluated. The results are discussed in comparison for the two materials.
Xiaozhi Hu, Brent Fillery, Tarek Qasim and Kai Duan
K.S. Kim et al., "Mean Stress and Ratcheting Considerations in Uniaxial Fatigue under Stress Control", Advanced Materials Research, Vols. 41-42, pp. 147-155, 2008