Double-Layered Cement Composites with Superior Electromagnetic Wave Absorbing Properties Containing Carbon Black and Expanded Polystyrene

Abstract

This paper reported that, using the method of double layer composite successfully prepared high performance of electromagnetic wave absorption materials. Such a composite is composed of a cement matching layer filled with expanded polystyrene (EPS) beads and an absorbing cement layer made of EPS beads and carbon black. The samples were tested by arching method in the frequency range of 8~18GHz. The reflectivities were revealed to be excellent, the lowest being-17dB. The new material can be used for building indoor electromagnetic radiation protection.

Preparation of a novel foamed concrete modified with carbon fiber and graphite: Mechanical, electro-magnetic and microstructural characteristics based on X-CT

“…Traditional cement-based materials with dense structures often have poor impedance matching, making it difficult for electromagnetic waves to enter [ 10 ]. With low density and low dielectric constant, porous materials like expanded polystyrene [ 11 , 12 ], hollow glass beads [ 13 ], and expanded perlite [ 14 , 15 ] are often incorporated into cement-based materials to improve impedance matching with free space [ 16 , 17 ]. However, foam concrete itself can extend the transmission length of incident waves and simplify the preparation process.…”

Preparation of a novel foamed concrete modified with carbon fiber and graphite:

“…Traditional cement-based materials have a dense structure and poor impedance matching, making it difficult for electromagnetic waves to enter [10]. With low density and low dielectric constant, porous materials such as expanded polystyrene [11,12], hollow glass beads [13], and expanded perlite [14,15] are often incorporated into cement-based materials to improve impedance matching with free space [16,17]. However, foam concrete itself can extend the transmission length of incident waves and simplify the preparation process.…”