Ar$χ$i-Textile Composites: Drapable Hybrid Woven Composites for Lightning Strike Protection

TL;DR

This work addresses the vulnerability of CFRP to lightning by introducing drapable, intralaminar hybrid weaving of stainless steel yarns with carbon fiber fabrics to form efficient LSP layers. The authors design three laminate systems (C/C, C/SS, C/C-SS) and fabricate single- and double-layer hybrid architectures, evaluating electrical resistance, arc-induced damage, and post-impact mechanical performance through quasi-static arcs and simulated lightning, micro-CT, and 4-point bending. Results show substantial reductions in surface temperature, through-thickness damage, and mass loss with hybrid layers, while residual flexural properties are better preserved than in reference CFRP, with two-layer hybrids offering the strongest protection due to dual-direction conductivity. The hybrid approach provides a scalable, drapable, fabric-form LSP compatible with prepregs and existing manufacturing, enabling safer, more durable woven composites for complex AAM and aerospace geometries.

Abstract

Carbon fiber-reinforced polymers (CFRPs) have been extensively used in the aerospace and wind energy industries due to their superior specific mechanical properties and corrosion resistance. However, their higher electrical resistivity makes them susceptible to lightning strike damage, which necessitates the addition of a surface lightning strike protection (LSP) layer. Traditional LSP systems, such as copper mesh or expanded foil, reduce lightning strike damage, but are not easily drapable around complex geometries and may introduce delamination-prone regions within the composite. Here, we propose a novel manufacturing strategy for architected hybrid composites as drapable LSP by weaving stainless steel yarns within the woven carbon fiber composites. We varied the metal-to-carbon yarn ratio and stacking configuration to assess damage evolution under quasi-static arc exposures and simulated lightning strikes. Our results elucidate that incorporating hybrid layers into composites significantly reduced surface temperatures, through-thickness damage, and mass loss under both electric arc impacts. The composites with the proposed LSP layers also exhibited higher retention of flexural modulus and strength compared to the reference CFRP. Advanced air mobility (AAM) vehicles, which operate at lower altitudes, face significant safety challenges due to their high susceptibility to lightning strikes. Therefore, the proposed hybridized composites can be used as an efficient and drapable LSP around complex shapes in AAM vehicles, offering enhanced safety and protection.

Figures (21)

• Figure 1: A 3D-printed airfoil core wrapped with bi-directional carbon fabric composite, featuring a hybrid weave with stainless steel yarns, applied to the leading edge for enhanced lightning strike protection.
• Figure 2: (a) Loom setup with 3K carbon fibers in the warp direction (out-of-plane) with a density of 13 ends per inch (out-of-plane); and (b) 3K carbon fiber, 24K carbon fiber, and stainless steel fiber yarns (from left to right) used in the current study.
• Figure 3: Hybrid weaves with 3K carbon fiber in the warp directions and (a) all stainless steel fiber yarn in the weft (C/SS); and (b) a combination of 24K carbon fiber and stainless steel fiber yarns in a 2:1 ratio in the weft (C/C-SS).
• Figure 4: Test setups for evaluating (a) the draping angle ($\phi$) of a fabric and (b) the electrical resistivity of a composite using the 4-probe method.
• Figure 5: Experimental setups for (a) quasi-static arc tests using a TIG welder; and (b) simulated lightning strikes conducted at Mississippi State University