Affiliation:
1. South China University of Technology
Abstract
Almost all load bearing components usually experience variable amplitude loading (VAL) rather than constant amplitude loading (CAL) during their service lives. The present study aims at evaluating residual fatigue life under VAL by adopting a dynamical coefficient mechanics (DCM) model which we have reported. New formulas connecting the crack length with number of cycles and expressions for the FCG rate under VAL have been derived and were used to predict crack propagation. The ratios of predicted-to-experimental lives range from 1.00 to 1.04, which indicates that the results obtained from this DCM model are in good agreement with experimental data from published literatures and cover all stages of fatigue crack growth curve.
Publisher
Trans Tech Publications, Ltd.
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