3903 Measurements of Crack Opening Displacement Distribution using Digital Image Correlation Method and Evaluation of Fatigue Crack Propagation Rate

Abstract

A digital image correlation method was used for measurement of COD distribution along the crack using slip pattern around fatigue cracks. In this measurement, selecting a subset in high contrast region was important for correct search. In addition, location of subsets near the crack and distance between subsets crossing the crack were found to have less effect on the COD distributions. Based on the COD distributions, stress intensity factor range ΔK_<est> was evaluated and used for estimating fatigue crack propagation rate.