Free Space Microwave Sensing of Carbon Fiber Composites With Ferromagnetic Microwire Inclusions

We provide new experimental results on studies of composites with glass-coated ferromagnetic microwires aligned with the requirements of carbon composites. This work focuses on the free space microwave measurements of composites made from carbon fibers and ferromagnetic microwires inclusion focusing on the electromagnetic properties. We prepared several glass-coated microwires and selected Co-based microwires with optimum soft magnetic properties and high magnetoimpedance effect for composite fabrication. We observed that by using a low-frequency modulating ac magnetic field parallelly oriented to the ferromagnetic microwires allows us to distinguish the microwave signals originated from the ferromagnetic microwires inclusions from the response generated by the carbon fibers. The location of carbon fibers near magnetic microwires has a critical effect on the response signals (parameters S amplitude) obtained from such composites.