English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The polyacrylonitrile (PAN) fibers go through a series of chemical reactions in various processing temperatures/stages and finally turn into the so-called carbon fibers. Oxidization is the first stage, and it takes the largest proportion of the entire processing time for the tremendous change from a chain texture to a ladder texture. The pre-carbonization of carbon fibers is then achieved using a furnace with a higher processing temperature (typically at 700–900 °C). During the reaction processes, the color of the fibers changes from white (PAN) to light black (oxidation), and eventually to black (pre-carbonization). Characterizing the complex permittivity helps us determine the carbonization status of the fibers. This work employed the enhanced-field method (EFM) and the contour mapping method to determine the fibers’ dielectric properties for the first time. Results show that both the real and imaginary parts of permittivity increase as the processing temperature rises. The dielectric constants change from 2.82 (PAN) to 6.50 (pre-carbonization), and the loss tangents increase from 0.007 (lossless) to 0.089 (lossy). This study provides a simple and effective method for characterizing carbon fibers’ processing status and can be applied to the measurement of other fibrous materials.

Characterizing the dielectric properties of carbon fiber at different processing stages