Local damage in a 5-harness satin weave composite under static tension: Part I – Experimental analysis

This paper presents an experimental damage analysis of a 5-harness satin weave carbon–PPS (polyphenylene sulphide) composite under uni-axial static tensile load. In order to understand the local damage behaviour, tensile tests were performed and accompanied by acoustic emission (AE) and microscopic analysis of the composite specimen. These tests enable us to detect the damage initiation stress as well as the damage initiation location in the composite. Microscopic observation of the tested composite laminates allowed the characterization of the sequence of intra-yarn transverse damage (perpendicular to the load direction) occurrence at different locations in the laminate, starting from crack initiation to the final failure of the composite.The earliest crack events occurred inside the laminate middle layers, followed by the damage on the traction free surface. It is observed that the initiation of the transverse crack, the location of the crack in the weft yarn cross-section (centre/near the edges) is affected by the relative position of the ply in the laminate (local nesting configuration). The first part of this paper deals with the experimental characterization of sequential damage in a 5-harness satin weave composite. Part II deals with the meso-FE modeling of damage using a satin weave unit cell, and the correlation between experimental and numerical results.