Electromagnetic absorber composite made of carbon fibers loaded epoxy foam for anechoic chamber application

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Vol. 220; pp. 59 - 65
• Main Authors: Méjean, Chloé, Pometcu, Laura, Benzerga, Ratiba, Sharaiha, Ala, Le Paven-Thivet, Claire, Badard, Mathieu, Pouliguen, Philippe
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.06.2017; Elsevier BV; Elsevier
• Subjects: Absorption; Anechoic chamber; Carbon fiber reinforced plastics; Carbon fibers; Carbon-epoxy composites; Complex permittivity; Composite materials; Computer Science; Dielectric properties; Electronics; Engineering Sciences; Epoxy foam composites; Microwave absorber; Networking and Internet Architecture; Particulate composites; Polymer matrix composites; Polyurethane; Polyurethane foam; Carbon fibers; Anechoic chamber; Composite materials; Dielectric properties; Epoxy foam composites; Microwave absorber
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2017.03.009

[Display omitted] •Carbon fibers loaded epoxy foam composites are proposed as microwave absorbers.•Dielectric properties (ε′, tanδ) of composites increase with carbon fibers content and length.•S11 coefficient of a pyramidal prototype was characterized in anechoic chamber.•Epoxy prototype shows better absorption performance than commercial absorber.•S11 of the prototype is lower than −30dB (4–18GHz) at normal and oblique incidences. This paper presents a new electromagnetic absorbing material developed from carbon fibers loaded epoxy foam for an application in anechoic chamber. The composite was developed in order to replace the currently used pyramidal absorbers made of carbon particles loaded polyurethane foam. Epoxy-composites filled with different weight percentages (from 0wt.% to 4wt.%) and length (1 and 3mm) of carbon fibers were achieved. After an optimization of the dispersion of carbon fibers in composite materials, the dielectric properties of the composites were measured using a coaxial-probe in the frequency range 4–18GHz. Results have shown that the complex permittivity of the composites increases with the amount of charge and also with the length of the carbon fibers. Absorption performance of a prototype prepared with a low concentration (0.5wt.%) of carbon fibers was measured in an anechoic chamber: it shows a mean gain of 10dB compared to a commercial absorber.