A comprehensive fatigue failure criterion based on thermodynamic approach

In this work, stress curve and energy-based (linear elastic strain energy, and hysteresis loop energy) fatigue failure criteria are compared with a new, entropy-based model for the prediction of fatigue life in a woven glass/epoxy laminate. Extensive experimental results are reported that involve load-controlled tension–tension fatigue test with two different stress ratios as well as constant- and variable-loading of a woven glass/epoxy laminate with various load angles. The plot of fracture fatigue entropy vs. fatigue life is compared with the energy plotted vs. number of cycle and stress plotted vs. number of cycle (i.e., the so-called S–N curve) plots.