A NOVEL TECHNIQUE FOR DETERMINING THE 3D SPATIAL-DISTRIBUTION OF GLASS-FIBERS IN POLYMER COMPOSITES

Over the past ten years, conventional 2D optical reflection microscopy has become a standard tool for inferring the fibre orientation distributions of both short- and continuous-fibre-reinforced composites. Recently, there has been a growing interest in determining the correlation of 3D fibre waviness and ply misalignment with compressive strength and failure mechanisms in unidirectional composites. Conventional optical reflection microscopy could still be used to investigate these phenomena by the analysis of multiple, polished and prepared sample sections and correlating fibre images between sections. However, we believe that the non-destructive, optical sectioning inherent in the confocal laser scanning microscope (CLSM) will make the CLSM a new standard research tool. 3D spatial distributions are reported for two totally different composites: (i) continuous, unidirectional glass fibres in a multiple ply, T800 epoxy and (ii) short glass fibres in polyoxymethylene which has been hydrostatically extruded.