Progressive damage in satin weave carbon/epoxy composites under quasi-static punch-shear loading

Damage evolution in composites during a high velocity impact is difficult to observe. In this work, quasi-static punch-shear (QS-PS) tests were conducted in an effort to determine damage that could develop during a penetrating impact event. Eight satin weave carbon/epoxy composite samples were fabricated and tested under different load levels. Load-displacement (P-delta) curves were obtained and type and extent of damage were identified in two/three dimensions using optical microscopy and X-ray computed tomography. Corresponding displacements at which the damage occurred were marked on the P-delta plots. A finite element analysis (FEA) was performed using the ABAQUS/Explicit commercial package with a progressive damage model to simulate experimental observations. It is found that the load pattern of the plate changes from local shearing to overall bending, which corresponds to the inflection stage of the P-delta curve. The final failure is caused by major delamination and fibre breakage due to shear and tensile stresses developed during the QS-PS tests. (C) 2014 Elsevier Ltd. All rights reserved.