Tunable electro-thermal system based on orientation and layup of highly-aligned carbon nanotube webs

Directly drawn carbon nanotube (CNT) webs were previously studied, by the authors, as a promising heating element for an electro-thermal anti-icing/de-icing system. Further tailoring of these electro-thermal properties may be achieved by the novel approach of exploiting the effect of the orientation and layup of these highly-aligned CNT webs, which exhibit anisotropic conductivity. Test coupons with different aspect ratios (L/W in 0.25, 0.73, 1.0, 4.0, 8.9) and web orientations (θ = 0°, 10°, 22.5°, 45°, 67.5°, 90°) were prepared and their conductivity compared to analytical predictions based on the conductivity theory of anisotropic solids with infinite and finite dimensions. Depending on the aspect ratio of the specimens, the conductivity as a function of web orientation is bound by two theoretical curves: L/W→0 and L/W→∞. Furthermore, heating elements with different CNT web layup were prepared, where it is shown that their electrical properties may be predicted by the analytical model. This study demonstrates that CNT web orientation and layup can be used to tune and pattern the electrical conductivity, as well as the heat distribution of an electro-thermal system. © CCM 2020 - 18th European Conference on Composite Materials. All rights reserved.