Title: Nondestructive, Noncontact Quantification of Carbon Fiber Alignment and Orientation By High-speed Microwave Ellipsometry

Authors: Nina P. Basta, Shridhar Yarlagadda, Dirk Heider, Edward J. Garboczi, Christian J. Long, and Nathan D. Orloff

DOI: 10.33599/nasampe/s.19.1371

Abstract: Novel short-fiber composites facilitate the manufacture of tailorable feedstock for small formed parts. In these composites, the alignment and orientation of the short fibers must be controlled to achieve the desired composite properties. While there are several processing variables that can be correlated to fiber alignment and orientation, there is a need for a fast, nondestructive, noncontact measurement technique to quantify local alignment and orientation in real time. Such a technique would enable real-time control of processing variables, resulting in higher quality composites. Here, we propose high-speed microwave ellipsometry as such a technique. To evaluate our approach, we measured five short-fiber composites samples made from a four-layer stack of carbon-fiber mats. These samples included one known control sample and four blind samples that were unknown at the time of testing. The four blind samples were known to be either a control, a sample with all layers rotated by 5°, a sample with a single unknown layer rotated by 5°, or a sample with a single unknown layer rotated by 15°. In this paper, we present our results demonstrating the effectiveness of this technique and discuss a path for real-time, large-scale imaging of fiber alignment and orientation.

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Conference: SAMPE 2019 - Charlotte, NC

Publication Date: 2019/05/20

SKU: TP19--1371

Pages: 11

Price: FREE