Prediction model for initiation in cracked component under very low cycle fatigue

In this paper, a model is proposed to predict the initiation cycle of a cracked component under very low cycle fatigue. The prediction model is based on the simple assumption that mechanism of crack initiation in a cracked component under very low cycle fatigue loading is the same as that under monotonic loading, and is given in terms of the plastic component of monotonic J and cyclic Delta J. For validation, predicted cycles are compared with displacement-controlled cyclic C(T) test data with two load ratios and load-controlled C(T) test data with two amplitudes. The predicted cycles based on 0.2 mm crack growth are similar in all cases.

Automated summary

This paper proposes a model to predict the initiation cycle of a cracked component under very low cycle fatigue, based on the assumption that the mechanism of crack initiation remains the same under monotonic loading. The predicted cycles are validated against different test data and show similar results in all cases.