LAUSR

Abstract Failure of materials subjected to torsional and axial cyclic loading is studied by applying the principles of thermodynamics of dissipative processes. Extensive experimental tests are conducted using stainless steel (SS) 304 and SS316 materials to gain insight into both torsional and tension–compression fatigue life. It is shown that the higher magnitude of dissipated energy in torsional loading, as reported in many studies, is due to the anelastic deformation in the material and its associated internal friction. It is further shown that proper assessment of the damaging dissipation energy requires one to exclude the non-damaging internal friction from the total amount of energy dissipation. Accumulation of thermodynamic entropy generation as an index parameter using the modified dissipated energy is estimated to predict the fatigue life. The experimental results are found to be in good agreement with the proposed fatigue life prediction.