The Composites Group at the National Institute of Standards and Technology has found optical coherence tomography (OCT) to be a powerful tool for non-destructive characterization of polymer matrix composites. Composites can be made more cost competitive by improved composite design, process optimization, and quality control. OCT can help address all three of the aforementioned challenges. OCT is a very versatile technique that can be applied to a variety of problems in polymer composites, for example, defect detection and damage evaluation.In this work, volumetric images of an epoxy/unidirectional E-glass reinforced composite are presented showing tow architecture and highly reflecting regions indicative of voids. Slicing of the volume at a particular depth reveals that point voids are actually channel-like voids that run in the direction of the fibers, as expected. The composite was then subjected to impact damage and a selected region of damage was analyzed. The damage was characteristic of a resin with some ductility indicating that the fiber-matrix interface was the weak component. The OCT images and laser scanning confocal microscopy results from the same sample are compared.
Proceedings Title: Proceedings of PLAST, Advancing with Composites 2000
Conference Dates: May 9-11, 2000
Conference Location: Milan, IT
Conference Title: PLAST 2000
Pub Type: Conferences
composites, damage, defects, imaging, microstructure, optical coherence tomography