Progressive damage analysis for cross-ply graded PE/PE composites based on cluster analysis of acoustic emission signals

The aim of this work is to identify the best strategy for cluster analysis of acoustic emission (AE) events for cross-ply PE/PE graded composites under tensile loading. Six cluster algorithms are made comparison. Peak amplitude and frequency centroid represent adequately AE events clustering to five groups for PE/PE graded composites. A link between five representative damage modes with corresponding five groups of AE event is established. The results can be used to distinguish damage mechanisms and to investigate damage evaluation of PE/PE graded composites, and damage initiation and propagation of a PE/PE graded sample under tensile loading are discussed. This study provides guides for the establishment of AE interpretation and identification of damage modes for ultra-high molecular polyethylene–reinforced composites in future studies.