An experimental criterion to detect onset of delamination in real time

Abstract

This study about the detection of delamination initiation is integrated into a wider project on the definition of a criterion of delamination on composite materials. It must therefore provide experimental data on the behavior of material to allow the formulation of a criterion of edge delamination as accurate as possible. Reliable experimental methods were used to identify the intrinsic parameters of the studied material. One of the most important procedures of this study consists in determining the onset of delamination in real time in order to determine stress level of delamination. Acoustic emission was used for detection of real-time damage initiation, using a location algorithm and specific pattern recognition. After correlation between experimental results and data processing, an acoustic emission signature of a delamination initiation was defined. Almost all experiments can be stopped before failure, in order to characterize damage. Extensive experimental work enabled us to verify the validity, the accuracy and the reliability of real-time delamination acoustic emission criterion.