A method for determination of parameters in total strain life equation

In order to improve the prediction precision of total strain life equation in a wide range of fatigue life with the equation parameters having definite physical significance, the relationship among parameters of total strain life equation, monotonic ultimate tensile stress and percentage reduction of area was established based on the physical significance of the fatigue strength coefficient and the fatigue ductility coefficient of total strain life equation. Parameters in the total strain life equation for TC4, GH4169 and GH901 alloy were fitted and fatigue life predictions were carried out combining with monotonic tensile and fatigue test data. The results show that fatigue life predictions using the total strain life equation with the parameters fitted by the developed approach give better estimation within a scatter band of about two for TC4, GH4169 and GH901 alloy.