《吸波材料英文版》課件

PPTcoursewareforEnglishversionofabsorbingmacontents目錄IntroductiontoAbsorbingMaterialsTheprincipleofabsorbingmaterialsPreparationmethodofabsorbingmaterialscontents目錄TheDevelopmentTrendsandProspectsofAbsorbingMaterialsResearchprogressofabsorbingmaterialsCHAPTERIntroductiontoAbsorbingMaterials01AbsorbingmaterialsaresubstantialthathastheabilitytoabsorbenergyorotherformsofradiationTheycanabsorbelectricalwaves,soundwaves,orotherformsofenergy,convertingitintoheatoranotherformofenergyDefinitionofabsorbingmaterialsAccordingtothetypeofenergyabsorbed,absorbingmaterialscanbedividedintoelectricalabsorbingmaterials,soundwaveabsorbingmaterials,andothertypesElectricalabsorbingmaterialscanfurtherbeclassifiedintoelectricalabsorption,magneticabsorption,andconductiveabsorptionmaterialsClassificationofabsorbingmaterialsInstainlesstechnology,absorbingmaterialsareusedtocoveraircraft,shipsandothervehicles,reducingtheirradarcrosssectionandmakingthemhardtodetectbyradarAbsorbingmaterialshaveawiderangeofapplications,includingradarabsorption,stainlesstechnology,electricalinterferencesuppression,heatpreservationandinsulation,soundabsorptionandnoisereduction,etcInthefieldofradarabsorption,absorbingmaterialscaneffectivelyabsorbincomingradarwaves,reducingtheradarcrosssectionoftargetsandmakingthemdifficulttodetectApplicationfieldsofabsorbingmaterialsInthefieldofelectricalinterferencesuppression,absorbingmaterialscanabsorbelectricalwavesgeneratedbyelectronicdevices,reducingelectricalinterferenceandimprovingsignalqualityInthefieldofheatpreservationandinsulation,absorbingmaterialscaneffectivelyabsorbandconvertheatenergy,improvingtheheatpreservationandinsulationperformanceofbuildingsandvehiclesInthefieldofsoundabsorptionandnoisereduction,absorbingmaterialscanabsorbsoundwaves,reducingnoiselevelsandimprovingacousticcomfortApplicationfieldsofabsorbingmaterialsCHAPTERTheprincipleofabsorbingmaterials02ElectricalwaveabsorptionoccurswhentheelectricalwaveaccountantsmaterialshavetheabilitytoconvertitsenergyintoheatorotherformsofenergyTheabsorptionprocessdependsonthefrequency,polarization,andpromotiondirectionoftheincidentelectricalwaveTheabsorptionefficiencyofamaterialistypicallycharacterizedbyitscomplexpermissionandcapabilityPrincipleofElectricalWaveAbsorptionTheabsorptionmechanismofabsorbingmaterialsElectricalwaveabsorptioninmaterialscanoccurthroughdifferentmechanisms,suchaselectricalrelaxation,magneticresonance,andinternationalpoliticalresonanceDielectricrelaxationoccurswhenthepolesinthematerialalignwiththeelectricfieldoftheincidentwave,leadingtoenergydissipationthroughinternalfrictionMagneticresonanceoccurswhenthemagneticmomentsinthematerialalignwiththemagneticfieldoftheincidentwave,leadingtoenergydissipationthroughheterosislossesInternationalpolarityresponseoccurrencesattheinterfacebetweenapolarmaterialandadielectricmaterial,wheretheincidentelectromagneticwaveexistssurfacepolaritiesthatleadtoenergyabsorptionThemicrostructureofthematerial,suchasitsporosityandgrainsize,cansignificantlyaffectitsabsorptionperformanceTheabsorptionperformanceofamaterialdependenceonmultiplefactors,includingitschemicalcomposition,microstructure,thickness,andsurfaceroughnessThechemicalcompositionofthematerialterminalsitselectricalrelaxation,magneticresonance,andotherabsorptionmechanismsFactorsaffectingabsorptionperformanceThethicknessofthematerialeffectsthenumberofabsorptionlayersrequiredtoachieveadesiredabsorptionlevelThesurfaceroughnessofthematerialcanaffectitsinteractionwiththeincidentelectromagneticwave,whichaffectsitsabsorptionperformanceFactorsaffectingabsorptionperformanceCHAPTERPreparationmethodofabsorbingmaterials03SolgelmethodisaversatileprocessforthepreparationofceramicandglassmaterialsItinvolvestheconversionofasolution(sol)toagelthroughaseriesofchemicalreactionsandphysicalprocessesInthismethod,precursorsolutionsarepreparedbydissolvingmetaloxidesormetaloxidesinappropriatesolutionsThesesolutionsarethenhydrogenized,polymeric,andcondensedtoformathreedimensionalnetworkofsolidparticlesTheresultinggelisdrivenandsinteredathightemperaturestoproducethefinalceramicmaterialThesol-gelmethodallowsforthepreparationofuniform,finegrainedmaterialswithcontrolledmicrostructuresandcompositions010203SolgelmethodThechemicalcoprecisionmethodisawidelyusedtechniqueforthepreparationofceramicpowderItinvolvesthecontrolledprecisionofsolutionsfromsolutiontoformapowdermaterialInthismethod,precursorsolutionscontainingthedesiredsolutionsaremixedwithaprecisionagentundercontrolledconditionsTheprecisionagentcausesthesolutionionstocomeoutofsolutionandformaprecisionTheprecisionisthencollected,washed,anddriventoretainthefinalceramicpowderThechemicalcopredictionmethodallowsforthepreparationofuniform,finegrainedpowderswithcontrolledcompositionsandparticlesizesChemicalcoprecisionmethodThemicroemulsionmethodallowsforthepreparationofuniform,welldistributednanostructuredpowderswithcontrolledparticlesizesandshapesThemicroemulsionmethodisaversatiletechniqueforthepreparationofnanostructuredmaterialsItinvolvestheuseofsurfactantsandcofactorstocreatethermodynamicallystable,nanoscaledropsofoilorwaterdisturbedinacontinuousphaseInthismethod,precursorsolutionsaremixedwithsurfactantsandcofactorstoformamicroemulationThemicroemulsionisthenfreefriedorotherwiseprocessedtoobtainthefinalnanostructuredmaterialMicrofusionmethodPyrolysisisaprocessinwhichorganicmaterialsarecomposedathightemperaturesinthepresenceofoxygenItiscommonlyusedtoconvertbiomassorwastematerialsintousableproductssuchascharcoal,gas,andoilInthismethod,theorganicmaterialisheatedquicklytohightemperaturesinacontrolledenvironmentTheheatinginvolvesthematerial,releasingvolatilegasesandliquidsaswellassolidcharcoalThevolatileproductscanbecollectedandrefinedtoobtainusefulfuelsorchemicalsPyrolysisisasustainableprocessforconvertingwastematerialsintovaluableproductswhilereducingenvironmentalimpactsPyrolysisCHAPTERTheDevelopmentTrendsandProspectsofAbsorbingMaterials041.HighperformanceabsorbingmaterialsrefertothosematerialsthathaveexcellentabsorptionpropertiesandcanmeettheneedsofspecificapplicationsWiththecontinuousdevelopmentofscienceandtechnology,moreandmorehighperformanceabsorbingmaterialshavebeendeveloped,suchasmetamaterials,carbonnanotubes,etc2.Theresearchanddevelopmentofhighperformanceabsorbingmaterialsaremainlyfocusedontheimprovementofabsorptionefficiency,thereductionofabsorptionloss,andtheimprovementofabsorptionstabilityInordertoachievethesegoals,variousnewtechnologiesandmethodshavebeendeveloped,suchasgeneticalgorithmoptimization,numericalsimulation,etcResearchanddevelopmentofhighperformanceabsorbingmaterialsLightweightandThinningofAbsorbingMaterialsInordertomeettheneedsofmodernwarfareandreducetheburdenoncarriervehicles,absorbingmaterialsareconsistentlybeingdevelopedinthedirectionoflightweightandthinningThiskindofmaterialhasgoodabsorptionperformanceunderthepromiseofreducingweightandthickness,whichcangreatlyimprovethesurvivalofcarriervehiclesinbattlefieldTheweightandthinningofabsorbingmaterialsrequiretheuseofnewmaterialsandtechnologiesForexample,itcanusethefoamingtechnologytoreducethedensityofabsorbingmaterials,orthemicronanoprocessingtechnologytoreducethethicknessofabsorbingmaterialsAtthesametime,italsoneedstoconsidertheimpactoflightweightandthinningontheabsorptionperformanceofabsorbingmaterialsTheapplicationprospectsofabsorbingmaterialsinstainlesstechnologyStealthtechnologyisakeytechnologyinmodernwarfare,whichcaneffectivelyreducetheradarcrosssectionandinfraredsignatureofaircraft,missesandotherweapons,improvingtheirsurvivalinbattlefieldTheabsorbingmaterialsareoneoftheimportantcomponentsofstainlesstechnologyInthefuture,withthecontinuousdevelopmentofstainlesstechnology,absorbingmaterialswillplayanincreasinglyimportantroleinmilitaryapplicationsInadditiontoaircraftandmisses,absorbingmaterialswillalsobewidelyusedinnavalships,groundvehiclesandotherfieldsAtthesametime,withtheconti