Damage Accumulation under Variable Loading of Cyclically Hardening Material at the Stages of Formation and Development of Cracks

Abstract

The results of experimental studies of the kinetics of damage accumulation at the stages of formation and rates of development of cracks in cyclic loading of the cyclically hardening AD-33 aluminum alloy are presented, and an assessment is made of the levels accumulated in the process of loading of damage on the basis of the deformation and kinetic criteria. It is shown that the limiting state (final fracture) during cyclic loading of an aluminum alloy is described well when using deformation characteristics (cyclically reversible deformations and one-sided accumulated ones at the stage of formation, and reversible and one-sided accumulated displacement of crack edges at the stage of crack development) used in the deformation and kinetic criteria. It has been established that a cyclically hardening aluminum alloy at the stage of crack development under tension-compression conditions does not obey the first model of fracture mechanics.