The Representation Of Reinforcing Fibres In Composites As 3d Space Curves

The automation of the Noran 'Odyssey' confocal laser scanning microscope (CLSM) for the scanning of unidirectional, glass-fibre-reinforced polymer composites is discussed. The CLSM enables the reconstruction of the 3D spatial distributions of fibres over significant sample volumes (1 mm x 1 mm x 50 mu m in XYZ) within reasonable timescales. Initial results are presented and the significance of intrinsic measurement errors is discussed. By representing each fibre within the measurement volume as a 3D space curve, it becomes possible to deduce the inherent 3D fibre waviness, localised fibre curvature, kappa and fibre torsion, tau. Also, fibre misalignment angles may be obtained to sub-degree precision and hence, in multi-ply composites, fibre and ply misalignment effects may be differentiated by inspection of these fibre angular distributions. (C) 1999 Elsevier Science Ltd. All rights reserved.