Design against fatigue. Basic design calculations.
Abstract:ESDU 75022 gives a calculation procedure to estimate the fatigue strength of a component (not subjected to fretting) having a stress concentration and under constant amplitude fatigue loading with a mean loading. The use of a fatigue strength reduction factor in place of the stress concentration factor is explained and curves give values for various materials and stress raisers. The effect of adjacent stress concentrations is also considered. The use is discussed of an equivalent stress where a combined loading or shear is applied. The method of taking into account the mean stress is explained and appropriate graphs to give fatigue strength in that case when it is known under zero mean stress provided. A comprehensive practical worked example illustrates the use of the method.
- Allowable Stresses
- Endurance (Fatigue Life)
- Fatigue Limit
- Fatigue Loading
- Fatigue Strength
- Fatigue Strength Reduction Factor
- Gerber Parabola
- Goodman Line
- Mean Stress
- Semi-Range/mean Stress Diagram
- Stress Concentration
- Surface Treatments
|Data Item ESDU 75022|
The graphs listed below are available only to subscribers.
|Figure 1a||m = 1.0, effect of mean stress|
|Figure 1b||m = 1.5, effect of mean stress|
|Figure 1c||m = 2.0, effect of mean stress|
|Figure 2||Fatigue strength reduction factor for notches of small radius|