Optimization towards Walker’s equation using intrinsic damage dissipation energy

Abstract

In this work, a fatigue stress equation associated with equivalent life is proposed based on the intrinsic damage dissipation energy. This method can be treated as an optimization towards Walker’s equation owing to the similarity between them. Compared to Walker’s equation, a modification of SWT function, the proposed equation is attached to a material parameter directly correlating with the fatigue strength exponent, which eliminates the need to conduct additional HCF experiments. The analysis of experimental results from the existing literature allowed for the comparative validation of the suggested equation with two existing equations that have wide acceptance and simplicity, namely the Goodman relationship and SWT function, which revealed a better performance of the suggested model. The proposal provides great potential for its simplicity in the evaluation of HCF lifetime under tensional fatigue loading with mean stress, further optimizing towards Walker’s equation.