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Indexed by:期刊论文

Date of Publication:2011-05-01

Journal:MATERIALS & DESIGN

Included Journals:SCIE、EI

Volume:32

Issue:5

Page Number:3017-3020

ISSN No.:0261-3069

Abstract:To solve more and more serious electromagnetic radiations, cement-based composites were prepared by introducing porous materials into cement. The reflection losses were studied using arched testing method in the frequency range of 1.7-18 GHz. The results showed that the absorption properties were improved obviously. The mechanisms of wave attenuation of the composites were discussed, which indicated that the scattering and multi-scattering in porous beads played an important role. The filling ratio of porous beads, the bead geometries as well as the conformation of cement all had noticeably influence on the absorption properties. The lowest reflection loss of -22 dB was obtained at 5.6 GHz when the specimen was filled with 50 vol.% expanded polystyrene, and the effective absorption bandwidth (less than -10 dB) reached 10.6 GHz when the specimen was filled with 50 vol.% expanded polystyrene and 2 vol.% carbon black. (C) 2010 Elsevier Ltd. All rights reserved.