A quantitative evaluation of ΔK_(eff) estimation methods based on random loading crack growth data

摘要

Methods for estimation of the effective stress intensity factor range (ΔK_(eef) are evaluated for narrow and wide hand random loading crack growth test data of 2024-T352 aluminum alloy. Three methods of estimating ΔK_(eff), conventional, 2/PIO and 2/PI methods proposed by Donald and Paris, are compared in a quantitative manner by using the results of fatigue crack growth life prediction under random loading, for three methods of determining K_(op), visual measurement, ASTM offset compliance method, and the neural network method proposed by Kang and Song. The 2/PI0 and 2/PI methods of estimating ΔK_(eff) provide better results than the conventional method for narrow and wide band random loading data, for all K_(op) determination methods examined.