Unraveling the effects of preform structures on the microstructure, electromagnetic shielding properties, and thermal conductivity of 3D orthogonal C/C composites

To expand the application of C/C composites in the field of 5G satellite, this paper explores the influence of different preform structures on the mechanical properties, EMI shielding properties, and thermal conductivity of C/C composites. Three common 3D fabric preform structures with different weaving parameters are designed. The pore evolution process of different samples was analyzed by image recognition processing method and pore partition method. The findings indicate that the 3D Fine weave pierced structure leads to higher graphitization degree. 3D orthogonal woven structure results in a higher compression strength of up to 240 MPa. Furthermore, the molding method of 3D orthogonal woven structure exhibits superior EMI SE and thermal conductivity. The EMI shielding mode of C/C composites is the coexistence of absorption and reflection. And excellent texture and a high fiber volume fraction are beneficial to improve thermal conductivity. In conclusion, 3D orthogonal woven structure is more suitable for producing C/C composites with high strength, superior EMI shielding, and enhanced thermal conductivity compared to 3D Fine weave pierced structure. This study reveals a new control method of high-performance materials for 5G satellites.