IHS ESDU Fatigue limit of unnotched steels (related to tensile strength). 88008

ESDU 88008 gives data for fatigue limit, or fatigue strength at high endurance for corrosion resistant steels which do not show a limit, for 240 different alloys. For axial, bending or torsional loading the relationship between the limit and the tensile strength is shown graphically and a statistical analysis defines a mean curve and curves for 10 and 90 per cent probability of survival with 95 per cent confidence. An example calculation illustrates how alternative values of probability and confidence can be used to define the limit. For axial loading the effect of the mean stress is shown. For the data under torsion a comparison is made with the prediction obtained by applying the von Mises criterion to the fatigue limit under bending. The material specifications, heat treatments and tensile strengths are tabulated together with the appropriate values of the fatigue limits obtained from the graphical presentation.