SBIR Phase I: Novel Three Dimensional Flocked Carbon Fiber Microwave Absorbers

This Small Business Innovation Research Phase I project will support the development, characterization, and commercialization of nonconductive, magnetically loaded, carbon fiber (CF) composite microwave absorbers. Manufacturers use absorbers to protect their products from unwanted Electromagnetic Interference (EMI) and to meet Federal Communications Commission (FCC) regulations and standards. EMI from external and internal sources can degrade the operation and performance of electronics. The demand for EMI absorbing materials that are cost effective, lightweight, thin, flexible and wide-spectrum continues to grow rapidly as microwave communications and mobile technologies become ubiquitous. The overall EMI shielding market exceeded $5.4 billion in 2015 and is expected to grow to $7.8 billion in the next 5 years. Absorber materials developed in this project can be applied to almost any type of antenna, circuit board, cable, gasket or enclosure. The project goal and broader impacts of this technology are development of lightweight, thin, high performance, microwave absorber materials that provide increased energy efficiency, design flexibility, reduced costs and improved connectivity for a wide range of markets, applications, products and devices. The product is suitable for many market sectors including automotive, consumer electronics, telecom and aerospace where thin, lightweight and wide-spectrum response is needed. The intellectual merit of the project will be the creation of new CF composites for microwave absorption. This project will measure and define the fundamental electromagnetic absorption parameters of these composites in the 1 - 12 GHz range. Characterization data such as dielectric constants, complex electric permittivity, magnetic permeability, loss tangents and layer thickness of the absorbers will be measured and derived. Such parameterization is essential for simulation modeling and design optimization of such absorbers for various markets and applications. Absorber attenuation and frequency response will be simulated and validated with laboratory transmission line and reflectivity testing. These composites use both magnetic and dielectric mechanisms to absorb microwave energy. Composite CF absorber materials are nonconductive and rely on insertion loss and impedance matching and/or cavity resonance effects. Processes, techniques and equipment needed for commercial production will be investigated. Graduate students and faculty will be supported in development of test, measurement and modeling techniques. The execution of the project will demonstrate the effectiveness and advantages of using CF composites as microwave absorbing materials and will provide a pathway to commercialization and product design. Successful completion of the project will create new high performance materials for the aerospace, automotive and consumer markets.