Prediction of fatigue strength under cyclic loading

Abstract

Main part of elements of constructions and machine parts operate under cyclic loading. Their working life cannot be determined on the basis of traditional criteria of strength, which generally do not take into account the process of the defectiveness, which is one of the characteristic and priority processes that occur under cyclic loading. The article proposes an approach to the assessment of long-term strength under the cyclic uniaxial loading on the basis of the heredity theory of defectiveness. The advantages of this approach are discussed. The analysis with the effect of the healing of defects was carried out. An approximate formula for the critical number of cycles of loading to damage in the absence of the effect of the healing of defects was found. This formula gives an estimate of long-term strength for the inhomogeneous one-dimensional stress state, determining the fatigue strength