Microwave-absorbing characteristics for the composites of TP(3)

C.-H.Pengetal./MaterialsScienceandEngineeringB117(2005)27–36

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Fig.1.Flowchartofexperimentalprocedureinthisstudy.

2.3.Measurementofmicrowave-absorbingbehaviorforferrite-TPUcomposite

TheabsorbingcompositematerialswerepreparedbymoldingandcuringthemixtureofferritepowdersandaTPUelastomer.TPUwasusedasapolymermatrixduetoitsgood exibilityandhigh llercontent.Itbecomesobvi-ousthathigh llercontentwouldenhancethecomplexper-mittivityofferrite-polymercomposite[21].Themixingratioofferrite-to-TPUwas xedat80%byweight.Thetestingspecimenshaveatoroidalshapewithboththicknessbeing1mmandouterandinnerdiametersbeing7.0and3.0mm,respectively.Themeasurementsofε ,ε ,µ andµ ver-susfrequencyweremadebycoaxialre ection/transmissionmethodusingaHewlett-PackardNetworkAnalyzer(Model:HP/8510C)ina2–12GHzfrequencyrange.