The electric and absorbing wave properties of fibers in structural radar absorbing materials

The electric and absorbing wave properties of fibers in structural radar-absorbing material are reviewed. Glass fibers and Kevlar fibers are transparent to radar wave. Carbon fiber graphited at high temperatures strongly reflects the radar wave. Ungraphited carbon fiber reflects radar wave when it is parallel to the electric filed and absorbs radar wave when it is perpendicular or oblique to the electric filed. The radar wave absorption of SiC fiber is related to the fiber's composition and processing temperatures. During fabrication of SiCf/glass-ceramic composites, reaction takes place between fiber and matrix. As a result, a carbon-rich layer interface is formed. It facilitates the radar wave absorption of the composites.