Tentative research for chaotic fatigue

The bifurcation and chaos theory of dynamic system were introduced to study the sudden change of fatigue behavior. The micro-model to describe the fatigue damage was proposed on the basis of physical mechanics. The local saddle-node (Hopf bifurcation) and global bifurcations (chaos) mechanisms for fatigue damage were analyzed and discussed. The numerical ranges of the parameters, while Hopf bifurcations occur, are given by means of the normal form theory and Hopf theorem, and the threshold value of the chaotic fatigue is given by computation for Melinkov function of the perturbed system.