Научный вестник МГТУ ГА (Nov 2016)
The linear model using in crack growth simulation under variable-amplitude loading
Abstract
The paper shows the possibility of using Paris-Erdogan equation for simulation fatigue crack growth under random loading. The considered equation has introduced the effective stress intensity factor range. The introduced methodology for crack growth simulation is based on the concept of a “basic” random loading. The discussed methodology included consideration of overloads influence on the fatigue crack growth. The theoretical model is based on the experimental researches of fatigue crack growth under random loading that have been realized during specimens fatigue tests of two Al-based alloys (D16chАТ - the same as 2024-T3, and В95АТВ - 7075-T6). In the tests the specimens of a center cracked panel were used. In all cases the random loading has been considered as Gaussian processes of cyclic loading with introduced and discussed parameters of investigated processes. As a result of investigations the model for estimation crack growth period in the different random of irregular cyclic loads was introduced.
