Abstract: Ceramic matrix composites (CMCs) combine high-temperature stability with tunable dielectric properties, making them ideal candidates for integrating load-bearing capacity and microwave absorption at elevated temperatures. This paper summarizes recent advances in microwave-absorbing CMCs from a multiscale design perspective. Four types of design strategies are addressed: fiber/matrix/interphase microstructures, fiber layup structures, whole woven structures, and topological structures. The corresponding microwave absorption mechanisms and regulation principles are elaborated as follows: microstructural design mainly optimizes impedance matching and dielectric loss by tailoring the electromagnetic parameters of fibers and matrices, as well as the composition and thickness of interphases. In fiber layup structure design, continuous-fiber layups construct thickness-direction impedance gradients through sequential stacking of fabrics with different dielectric properties, while discontinuous periodic-pattern layups further introduce resonant absorption mechanisms. Whole woven structure design replaces two-dimensional fabric stacking with three-dimensional fiber networks, increasing interfaces and scattering paths to enhance attenuation efficiency. Topological structure design, utilizing unit cells such as honeycombs, stepped configurations, and Triply Periodic Minimal Surfaces, overcomes the limitations of intrinsic material parameters through structural resonance, achieving broadband absorption. Finally, key challenges including unclear cross-scale coupling mechanisms and insufficient engineering validation are discussed, along with future directions such as multiscale synergistic design, temperature-adaptive absorption, and integrated forming of complex structures. This work provides a reference for the architectural design and engineering application of microwave-absorbing CMCs.

Key words: microwave absorption performance, ceramic matrix composites, multiscale design, review