Design of a composite metamaterial toward perfect microwave absorption and excellent load-bearing performance

In this paper, an ultrathin layer of arrayed electromagnetic resonators is introduced on the CFRP laminate to form a meta-CFRP composite. It is quite an exciting and promising design, as the composite metamaterial not only inherits the advantages of the CFRP composite in mechanical performance but can also obtain on-demand microwave absorption properties rather than purely reflective as neat CFRP laminates. Here, several meta-CFRP samples have been prepared by a co-curing process. Near-perfect microwave absorption (i.e., S11 ≤ -10 dB) has been achieved in a series of situations such as under normal incidence and a constant polarization angle, under oblique incidence and an arbitrary polarization angle, and for a relative broadband microwave absorption (11.28 GHz ∼ 12.52 GHz). Moreover, the mechanical properties of the fabricated meta-CFRP samples, including tension, compression, bending, and shear, have also been investigated, which showed an increase of more than 680% compared with previous microwave absorbers. The present work provides a new idea for designing electromagnetic and mechanical dual functional materials, based on which many new materials, for example, strong materials with tunable microwave absorption, can be further developed in the future.