Application of the fracture mechanics and reliability methods to the fatigue problem

The fatigue problem of high strength materials and complex mechanical systems subjected to cyclic loadings and corrosion environment is studied. It is assumed that the element of a system contains the initial cracks with the sizes expressed in the form of Weibull distribution. The kinetic equation of corrosion fatigue cracks growth, describing the cracks growth under Paris's law in the absence of the corrosion environment and purely corrosion growth of cracks in the absence of external stresses is developed. Taking into account that the reliability of the system as a whole depends on the reliability of individual elements and the type of their connection, the different types of connection, in particularly, in series, parallel and with reservation are considered. For each system the reliability function and the corresponding fatigue strength criterion are formulated. (C) 2014 Published by Elsevier Ltd.