Three-dimensional multi-material electromagnetic band-gap structure: design, fabrication and property studies

摘要

Purpose - The purpose of this paper is to bring up the concept of multi-material electromagnetic band-gap structure (EBGs) and develop a method for its fabrication. Meanwhile, its microwave properties were studied and compared with the traditional EBGs consisting of two kinds of material. Design/methodology/approach - Stereolithography (SL) and gel casting were used to fabricate 3D multi-material EBGs. Resin mold was designed and fabricated based on SL process, slurries loaded with 55vol per cent Al_2O_3 and 55vol per cent TiO_2, respectively, were prepared, and using gel casting, multilayer EBGs with diamond structure were fabricated. T/R method was used to obtain the characteristic parameter S_(21) of the EBGs; meanwhile, characters of their band structure were studied based on plane wave expansion method. Findings - The fabricated EBGs with a TiO_2-resin-air structure showed a band gap from 11.7 GHz to 16.0 GHz along, 1, 1, 0. direction; the EBGs with a TiO_2-resin-Al_2O_3 structure showed a band gap from 11.4 GHz to 11.9 GHz along, 1, 1, 0. direction. Both of them agreed well with the simulation result. Also, through the study of multi-material EBGs' microwave properties, it could be seen that this structure was a good approach to adjust the band gap. Originality/value - With the concept of multi-material EBG structure brought up, multilayer 3D EBGs were designed and fabricated based on SL combined with gel casting. It could be seen that multi-material EBGs was a good approach to adjust the band gap. Also, the fact that the testing result matched the simulation validates the feasibility of the process.