Joule Heating of Carbon Fibers and their Composites in Radio Frequency Fields
Abstract
Carbon fibers (CFs) show the ability to generate heat when exposed to radio frequency (RF) fields, but little is known about the relationship between material properties and the heating behavior. Our group has previously shown that this heating response can be used for the manufacturing of CF-reinforced composites. Here we analyze the effect of electrical conductivity on the RF-induced Joule heating patterns of CFs. Unidirectional CF tows and their composites show different heating rates when their orientations relative to the RF field lines are changed due to their anisotropic conductivities. We observed that the CFs and their composites showed higher heating responses when they were placed perpendicular to the RF field lines. We observed an increase in the heating response with increasing conductivity; however, beyond a certain conductivity value, the heating response decreases because the samples with very high conductivities reflect the RF field. We also simulated the RF-induced heating of unidirectional CF tows in different orientations, with qualitative agreement between experimental results and simulations. The findings of this work explain the effect of electrical conductivity on field-induced Joule heating of carbon fibers; these results pave the way for energy efficient, out-of-oven processing of thermoset composites at an industrial scale.
Citation
Dasari, Smita Shivraj (2023). Joule Heating of Carbon Fibers and their Composites in Radio Frequency Fields. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /199170.