The analysis of features of slow growth of fatigue cracks in metals

In paper the theoretical analysis of features of development the slow growth fatigue cracks in zones of dangerous section of the details saving a carrying capacity in machines safe resource is presented. Fatigue breaks with various critical depths of slow growth fatigue cracks as result of complex influence of inter-dependent factors at curving and torsion on symmetric cycle of identical samples are reduced. It is estab-lished that at normal temperature and frequency of 19,5 Hz critical depth of fatigue crack depends on type and scheme of loading, structure and viscosity, class of materials, degree of strength concentrations, the size of dangerous section, loading amplitude.