In this paper, we present the design of multilayer microwave absorbers comprised of Co Fe alloy nano-particles and nano-flakes as fillers. The thickness of the unite layer is optimized by using the Genetic Algorithm. ...In this paper, we present the design of multilayer microwave absorbers comprised of Co Fe alloy nano-particles and nano-flakes as fillers. The thickness of the unite layer is optimized by using the Genetic Algorithm. Efficient microwave absorptions over a wide frequency band and a range of incident angles are achieved by using multilayer absorbers. We show that the absorbers are effective not only for a planar surface but also for arbitrarily shaped objects as well.展开更多
Composites were prepared with polysulfone through ex-situ toughening technique. The dynamic parameters of cyanate/epoxy resin were studied by differential scanning calorimetric(DSC) analysis and dynamic mechanical a...Composites were prepared with polysulfone through ex-situ toughening technique. The dynamic parameters of cyanate/epoxy resin were studied by differential scanning calorimetric(DSC) analysis and dynamic mechanical analysis(DMA). Microstructual toughening mechanism was studied through scanning electron microscopy(SEM). The particle microstructure in interlaminar region of composites toughened through ex-situ toughening technique revealed that a reaction induced phase decomposition and phase inversion happened in the interlaminar region. The thermosetting particles were surrounded by the PS phase, which could signifi cantly improve the delamination resistance of composites. The compression after impact(CAI) can be signifi cantly improved from 180 MPa to 260 MPa by using ex-situ toughening while the mechanical properties are not affected.展开更多
文摘In this paper, we present the design of multilayer microwave absorbers comprised of Co Fe alloy nano-particles and nano-flakes as fillers. The thickness of the unite layer is optimized by using the Genetic Algorithm. Efficient microwave absorptions over a wide frequency band and a range of incident angles are achieved by using multilayer absorbers. We show that the absorbers are effective not only for a planar surface but also for arbitrarily shaped objects as well.
基金Funded by the National Natural Science Foundation of China(51373137)
文摘Composites were prepared with polysulfone through ex-situ toughening technique. The dynamic parameters of cyanate/epoxy resin were studied by differential scanning calorimetric(DSC) analysis and dynamic mechanical analysis(DMA). Microstructual toughening mechanism was studied through scanning electron microscopy(SEM). The particle microstructure in interlaminar region of composites toughened through ex-situ toughening technique revealed that a reaction induced phase decomposition and phase inversion happened in the interlaminar region. The thermosetting particles were surrounded by the PS phase, which could signifi cantly improve the delamination resistance of composites. The compression after impact(CAI) can be signifi cantly improved from 180 MPa to 260 MPa by using ex-situ toughening while the mechanical properties are not affected.