Fabrication and Thermos–Mechanical Coupling Characterization of Needle‐Punched Z ‐Directionally Reinforced Carbon–Glass Hybrid Composites

A carbon–glass hybrid needle‐punched composite material was developed to fulfill the requirements of integrating heat insulation and load bearing in aircraft cable sheaths. A systematic investigation was conducted on the tensile, compressive, and interlaminar shear properties, as well as the thermal conductivity and coefficient of thermal expansion of the material at temperatures of 25°C and 300°C. The effects of the carbon–glass ratio and carbon fiber type on the material properties were examined, and it was determined that the optimal proportion is 20% T300 carbon fiber combined with 80% glass fiber. Compared with the existing 2.5D carbon–glass woven/BMI composites, the optimized hybrid composites exhibited a 4%–21% increase in tensile strength, a 19%–247% increase in compressive strength, a 36%–79% increase in inter‐laminar shear strength, and a two‐thirds reduction in manufacturing cost—with only a 20% decrease in thermal insulation performance. This study presents a novel design approach and theoretical guidance for aircraft cable sheath.