Three-dimensional woven structural electromagnetic composite metamaterial with lightweight, anti-delaminate and in-phase reflection properties

Electromagnetic metamaterials are capable of tuning or controlling the transmission of the electromagnetic waves to realize high-performance microwave devices. However, the poor mechanical properties caused by the multi-layer structure limited its wide applications, especially in aircraft, satellites or high-speed vehicles. In this study, an electromagnetic metamaterial with in-phase reflection property was integrated into the three-dimensional (3D) woven composite to achieve the combination of unique electromagnetic properties and excellent mechanical properties on multi-functional composites. The 3D electromagnetic composite metamaterial was capable of reflecting electromagnetic waves from the antenna back lobe to the main lobe at 0° phase, resulting in the bandwidth of the test antenna increased from 0.6 GHz to 1.2 GHz, and the gain increased from 2.8 dB to 4.8 dB, an increase of 71.4 %. Owing to the tight physical bonding of binder yarn, 3D electromagnetic composite metamaterial exhibited excellent anti-delaminate performance and stable electromagnetic properties in 28 J impact. The impact damage threshold energy of the 3D electromagnetic composite metamaterial was significantly increased from 10 J to 30 J.