Abstract:Studyanddevelopmentofpolyimideadhesivefilmsaresummarized.Thesyntheticmethods andtherelationshipsbetweenstructuresandpropertiesofthermosettingandthermoplasticpolyimideadhesivefilmsarediscussed. Thedevelopmenttrendsofpolyimideadhesivefilmsinthefuturearealsoanalyzed.

Abstract:

Inthethesis,themeasuringmethodsofelectromagneticparametersofmagneticthinfilmand thetechnicalfeaturesinthelast15yearsaresummedup,whichincludestrip-linemethod,micro-stripline method,waveguidemethod,coplanarwaveguidemethod,terminalimpedancemethod,terminalshort-circuit methodandresonantcavitymethod.

Abstract:

Progressinpolymermatrixcompositebondingtechniqueisreviewed.Theprocessforimprovingthe strengthofbondedcompositejoints,adhesivematerialsandtheeffectonbondingdurabilityaresummarized.Adherendsincludethermosetandthermoplasticmatrixcompositesbondedtothemselves,andalsocompositesbondedto metals.Therearesignificantdifferenceinpropertiesofcompositebondingduetocompositetypes,adhesivetypesand differentsurfacepretreatmenttechnique.Togainhighstrengthanddurabilityforbondedcompositeparts,alotof workshouldbecarriedoutinselectionofadhesiveandcompositesystems,surfacetreatmentofcomposite,testevaluationofbondedsystemsanddesignofbondedjoints

Abstract:Theheattransfermechanismofsilicaaerogelwasstudiedbyusingthekinetictheory.Basedonthefeaturesofthemicrostructureofsilicaaerogel,nanoporemodelwasbuilt.Theexpressionofthethermalconductivityofgas innanoporewasderivedwithtakingaccountoftheinteractionforceofmolecules.Thethermalconductivityofgasinsilica aerogelwasachievedwiththederivedexpression.Aheattransfermodelofsolidmatrixunitobtainedfromthestructure ofsilicaaerogelwasdeveloped.Accordingtothekinetictheory,theeffectivethermalconductivityofsilicaaerogelwas obtained.Theresultsshowthattheaveragegasmoleculefreepath,theinteractionforceofmoleculesandtheforcebetweenmoleculeandwallarethemajorfactorswhicheffectthethermalconductivityofgasinsilic aerogel,thediameters ofsolidmatrixunitandcontactinterfacearemainfactorsaffectingthethermalconductivityofsolidmatrixunit,thepore sizedistributionseriouslyaffectstheequivalentthermalconductivityofsilicaaerogel.

Abstract:Thereductionofradiationtransferisthekeytoimprovethermalinsulatingpropertiesofnano silicaporousthermalinsulating materialathightemperatures.Theeffectofzircononthermalinsulating propertieswasinvestigated.Theresultsshowthattheintroductionofmicro-zirconcangreatlyreduceIRradiationtransferandimprovethermalinsulatingpropertiessignificantlyathightemperatures. Whenzircon withmassratio35%isadded,thermalconductivitycandecreasefrom0.119W/(m·K)to0.053W/(m·K) at500℃.Inaddition,themechanismofIRopacificationofzirconisalsodiscussedandanalyzed

Abstract:RheologicalbehaviorofJF-45epoxy/cyanatecopolymerwasstudied.Arheologicalmodelbasedon Dual-Arrheniusequationwasestablishedwithexperimentaldataandusedtosimulateandforecasttherheologicalbehaviorofthiscopolymer.
TheresultsindicatethattheestablishedrheologicalmodelforrelativeviscosityisingoodagreementwithDual-Arrheniusequationattemperaturerangefrom80℃to160℃.Theinitialviscosityishigherbelow160℃ duetothelowreactiverateofthecopolymer.Theinitialviscosityofthecopolymerisdecreasedwiththeincreaseoftemperature.Theviscosityisincreasedrapidlyattemperaturemorethan170℃.Thecuringprocessisalsoestablishedbased onDSCcurvesandDual-Arrheniusequation.

Abstract:ThethermalshockbehaviorofZrB2-20%SiC-6.05%ZrCcompositesfabricatedwithin-situmethod andhot-pressingwasstudiedbymeansofquenchingintowaterfromhightemperatures.Theeffectsofthermalshock temperaturedifferences,cool(25℃ofbathtemperature)andboilingwaterascoolingmedium,singleandfivecyclic shocksandhightemperatureoxidationonthermalshockresistanceofsamplesfabricatedthroughin-situmethodwere investigated.Thethermalshockresistanceparametersofsamplesfabricatedthroughin-situmethodandhotpressing werecomparedandthenthemechanismofthermalshockresistancewasalsodiscussed.Theresultsshowthatthermalshockpropertyofin-situsamplewasbetterthanthatofhot-pressingsample

Abstract:Newglassfiberreinforcedsilicon-containingarylacetyleneresin(SCAR)compositeswerepreparedfromSCARandglassfibercloth. Theinfluenceoftheresincontent,moldingtemperatureandmolding pressureontheflexuralpropertiesofthecompositeswasinvestigated.Onthebasisofthedeterminedcuring process,theoptimum manufacturingconditionsfortheSCARcompositeswereobtainedasfollows:the moldingpressure1.0MPa,theresincontent31% wtandtemperatureprocedure170℃/2h+210℃/2h+250℃/4h.Theflexuralstrengthofthecompositereach278MPa.

Abstract:Anultra-widebandradomecoveringX-toKa-bandwasdevelopedbyusingAI-SI-AGanalysis methodforthedesignoftheelectricpropertyoftheradome,byselectingadvancedwave-transmissionmaterialsandbyoptimizingthemanufacturetechnology.Theresultsshowthatelectricpropertiesinwidebandare stable,alsoareinagreementwithgeneralspecificationsoftheradome

Abstract:Twoseriesofphenylethynylend-cappedpolyimideoligomersweresynthesizedandtheirthermaland rheologicalandmechanicalpropertieswerecharacterized.Theresultsshowthattwooligomersexhibitlowcomplexmelt viscosity(<1Pa·s)at280℃/2handarestableatthistemperature.Thesetwooligomerscanbeprocessedbyresin transfermoldingtechniques.TgandT5dofPI-1resinsare402℃and534℃respectively,PI-2resinsare356℃and 525℃respectively.TheretentionratesofpropertiesofPI-1resin/carbonfabriccompositearebeyond70%at300℃.

Abstract:Twokindsofself-catalystcyanoresinwithNH2-groupandimidestructureinthemainchain weresynthesized,whosestruturewerecharacterizedwith1H-NMR.DSCwasusedtoinvestigatethecuring behaviorofthecyanoresinandcomparisonwasmadewithotherself-catalystmonomer.Thestructureand thermalpropertiesofcuredresinwerestudiedwithFTIRandTGArespectively.TheresultsofDSCshow thatbothoftheself-catalystcyanoresinsgiveonexothermicpeakfrom250to300℃ aftermelting,dueto thecuringreaction.Furthermore,FTIRspectrademonstratedthattheexpectedstructuresofcuredresins areformed.Andtheresinshaveexcellentthermalproperty,Td5ofwhichisabove510℃notonlyinnitrogen
butalsoinair,thedecompositionresiduesofwhichisover60%innitrogenat900℃.

Abstract:Toexploretheeffectofcuringbystepsonpropertiesofradomemadeofmoderatetemperaturematerialsystem,themechanicalandelectromagneticpropertiesoflaminateandhoneycombsandwichspesimenaftermadeofmoderate temperaturematerialsystemincludingSW-280A/epoxyprepreg,FM73MfilmandNomexhoneycombmulti-curingwasdiscussedinthispaper.
Theresultsshowthattherearesmallchangesinmechanicalpropertiesandelectricpropertiesandno significantdownwardtrendafterfirst,second,third,fourthandfifthcuring.Thisimpliedthatcuringbystepsdoesn’thave affectthemechanicalandelectromagneticpropertiesofthemoderatetemperaturematerialsystem.Soradomesmadeofthe materialsystemcanbemanufacturedwithcuringbystepsandcuringbystepsdoesnotaffectthemechanicalandelectromagneticpropertiesofradome

Abstract:Aluminaaerogelswerepreparedthroughadditionofpropyleneoxidetoaqueousorethanolicsolutionsof hydratedaluminumsaltsAlCl3·6H2O,followedbydryingwithsupercriticalethanol.Microstructureofaluminaaerogels werecontrastedandanalyzedatdifferenttemperaturbymeansoftransmissionelectronmicroscopy,powderX-raydiffractionandnitrogenadsorption/desorptionanalysis.Theresultsshowthattheaerogelmicrostructurescontainhighly reticulatednetworksofboehmitefibers,nosignificantlossinmonolithicityoccurredduringheattreatmentofalumina aerogelsat500℃and1000℃,thesurfaceareais429m2/gand174m2/g.Thephaseconversionintherangefrom20 to1000℃areasfollows:boehmite→γ-Al2O3→δ-Al2O3.

Abstract:Porousyttria-stabilizedzirconia(8mol%Y2O3-ZrO2,8YSZ)ceramicswasfabricatedbytert-butylalcohol (TBA)-basedgel-castingprocess.Atafixedsolidloadingof10vol%oftheinitialslurry,theinfluenceofsinteringtemperatureontheporosity,openporosity,poresizedistributionandmicrostructurewasdiscussed.Therelationshipbetweencompressivestrength,roomtemperaturethermalconductivityandmicrostructurewasalsodiscussed.Porous8YSZceramicswith highporosityrangingfrom65%to74% wasfabricatedbyadjustingsinteringtemperature.Auniformporesizedistribution wasobserved,andthemeanporesizerangedfrom0.68to1.82μm.Thecompressivestrengthsofporous8YSZceramics
werebetween7.92and13.15MPa.Thethermalconductivityofporous8YSZceramicsatroomtemperature(aslowas0.053W/m·K)wasoneorderofmagnitudelowerthanthatofdense8YSZceramics(~2.2W/m·K),anddecreasedwithincreasingsinteringtemperature.

Abstract:Byusinggel-castingprocess,poroussiliconnitrideceramicsofdifferentratiosbetweenmonomerandcrosslinkerwerepreparedundertheconditionofafixedtotalamountbutdi ferentproportionofmonomerandcross-linkingagent.Theeffectsofdifferentproportionofmonomerandcross-linkingagentonthemicrostructureandmechanicalproperties ofporoussiliconnitridewerestudiedbymeansofthescanningelectronmicroscopy(SEM),archimedesmethodandthreepointbendingmethod.Theresultsshowedthatthedryingshrinkageofspecimensincreasedastheproportionofmonomer andcross-linkingagentincreased,thespecimenscrackedafterbindersburningwhentheproportionofmonomerandcrosslinkingagentwasaboveorequal15.However,thosesinteringspecimenswithproportionsofmonomerandcross-linkingagentbelow15displayedarisingtrendofstrengthastheproportionincreased.

Abstract:C/C-ZrCcompositeswerefabricatedbyinner-modificationmethodviaintroducingZrCintoC/Ccomposites.ThestructureandmorphologyofthecompositeswerecharacterizedbyXRD,SEMandEDSanalysis,andthemechanicalpropertiesofthematerialswereinvestigatedbythreepointbendingtests.TheeffectofZrCadditivesonfracturebehavior ofthecompositeswasstudied.TheresultsshowthattheZrCphaserevealsacontinuousdistributioninthecomposites.Comparedwithcarbon/carboncompositeswithoutZrCadditives,theflexuralstrengthofC/C-ZrCcompositeswasincreasedbyabout33.39%
thanthatofthenakedC/Ccomposites,andthefracturemodeofthecompositeswastransformed fromtoughnesstobrittlenessaftertheZrCaddition.Thechangeofthefracturemodewasmainlycausedbytothestronginterfacecombinationbetweenthecarbonfibersandthesubstrate.

Abstract:Basedontheobservationofthemeso-structureof2.5Dbraidedcomposites,athree-dimensionalmechanical modelispresented,whichismorestableandisabletoreflectthestructureofthiscomposites.Therelationshipbetweenthe fibervolumeandgeometricparametersisdeducedbyusingthismodel.Thestiffnessaveragemethod(SAM)andfiniteelementmethod(FEM)areadoptedtopredicttheeffectivemechanicalproperties.Theelasticconstantsvaryingwiththechange offibervolume,warpdensityandweftdensityareanalyzed.Bothofthepredictedresultsshowthecamberangledoesnot noticeablyaffecttheelasticproperties,buthasanotableimpactonthemeso-stressfield.ThetheoreticalpredictionisinaccordancewiththeFEMresults,whichverifiesthevalidityofthemodel

Abstract:ThesamplesofabsorbinghoneycombwerepreparedbyusingNomexhoneycomb,multicomponentabsorbentandphenolicresin.Effectsofheight,thicknessofsheetandcontentoftheabsorbentofthe honeycombonradarabsorbingpropertiesofthehoneycombsandwichwereinvestigated.Theresultsindicate thateffectivebandwidthinwhichreflectivityislessthan-10dBextendstolowfrequencyasheightofthe honeycombincreases,asthicknessofthesheetincreases,reflectivityoftheabsorbinghoneycombsandwich inlowfrequencybanddecreasesandthatinhighfrequencybandincreases,dipfrequencyofthereflectivity lowersastheweightoftheabsorbentadheringtothehoneycombwallincreases.

Abstract:Rigidthermalinsulatingmaterials(RTIM)werepreparedfromceramicfibersthroughsintering.Theeffectsof density,fiberorientation,testtemperatureandcompositionwithaerogelonthemechanicalpropertiesoftheRTIMwereinvestigated.TheresultsindicatethatthemechanicalpropertiesoftheRTIMincreasewiththeincreasingofthedensity.Tensile andcompressivepropertiesoftheRTIMinplanedirectionarefourtimeslargerthanthatinthicknessdirection.ThecompressivepropertiesoftheRTIMat800℃ and1000℃are90%and50%ofthoseatroomtemperaturerespectively.The compressivepropertiesofcompositesincreasedby35%aftercompositionwithaerogel,whilethetensilepropertiesofcompositeskeepunchanged.

Abstract:Therelationshipbetweenmechanicalpropertiesofceramicinsulatingtileanddensitywasinvestigated.Itisfoundoutthattheuniformityofdensityhasasignificantinfluenceonthemechanicalproperties.Ceramicinsulatingtilewithexcellentmechanicalpropertieswasfabricatedbyanoptimizedprocess,the mechanicalpropertieswereimprovedfrom0.250MPato0.786MPa.Theresultsshowthattheincreaseof thedensityuniformityisaneffectivewaytoimprovethemechanicalpropertiesoftheceramicinsulatingtile.

Abstract:UltrasonicvibrationgrindingforC/Ccompositesisintroduced.Superiorityofthistechniqueis demonstratedincomparisonwithtraditionalgrinding.Orthogonalexperimentwasusedtoanalyzethequality ofthecompositesurfaceandtherelationsbetweenthefactorsofultrasonicvibrationgrinding.Thusthemain factorsaffectingthevibrationgrindingarefoundout.

Abstract:SiO2aerogelsreinforcedbyceramicfiberswerepreparedbysol-gelmethod.BoththeSiO2aerogelsandthecompositeweretreatedunderdifferenttemperatures.SEM,N2adsorption-desorptionandthermalconductivitydevicewereadoptedtocharacterizethestructureandthermalconductivitypropertiesofthe preparedmaterials.Theresultsshowthatthemicrostructurechangeslittleafterheatingunder700℃andthe heatinsulationpropertiesmaintainsalmostunchanged.However,afterheattreatmentat1000℃,theheatinsulationpropertiesdecreased,nano-microstructuressinteredandtheamountofporesreduced.

Abstract:ThenanostructuredzirconiaTBCsweremanufacturedbyatmosphericplasmasprayingwith thenanostructuredzirconiaagglomeratedpowders,andtheCO2laserbeamwiththecontinuouswavewasappliedtothelaserglazingofnanostructuredTBCs. Themicrostructures,microhardnessandthermalshockresistanceofnanostructuredTBCsandas-glazedTBCsweresystematicallyinvestigatedcomparedwithconventionalTBCs.TheresultsshowthatthenanostructuredTBCsexhibitauniquecomplexmicrostructureconsistingofcolumnargrainsandnon-meltedorpartiallymeltednanosizedparticles,whilethemicrostructureof theas-glazedcoatingsisacombinationofthecolumnargrainsinthefractureandtheequiaxedgrainsonthe surface.Theexpeirimentalresultsofthemicrohardnessandthermalshockresistancepresentthatthenanostructuredcoatingsandtheas-glazedcoatingspossessbetterpropertiesthantheconventionalcoatings.Sothe hybridprocesswherethenanometertechnologyandlaserglazingarecombinedwithatmosphericplasma sprayingtoprepareTBCsisrevealingahighpotentialfortheimprovementofTBCsproperties.

Abstract:Hightemperatureflexuralstrengthofporoussiliconnitrideceramics(nolessthan50% porosity)undervacuumconditionswasstudied,andthephasesafterhightemperaturestrengthtestingwasanalysedalso.Theresultsshowthattheflexuralstrengthofporoussiliconnitrideceramicsisnegativelyrelatedwithtemperatureundervacuumcondition.Thesofteningofglassyphaseongrainboundaryunderhightemperatureisthemainfactorinfluencingthestrengthdecrease.

Abstract:Graphitizationdegree,latticeconstantandcrystallitesizesofthreekindsofC/Ccompositesweremeasured byrietveldrefinementmethod(wholespectrumfitting)ofX-raydiffraction.Theresultsshowthatstandarddeviationof crystaltheparameterofthethreeC/Ccompositesislessthan2.0×10-3,standarddeviationofgraphitizationdegree(g)is lessthan1.5,standarddeviationofcrystallitesizes(Lc002)islessthan0.5.RietveldrefinementmethodofX-raydiffractionis effectiveforinvestigationofthecrystalparametersofC/Ccomposite.

Abstract:MicrostructuresandsurfacechemicalandphysicalcharactersofM40JandT300carbonfiberswereinvestigatedbyscanningelectronmicroscopy,transmissionelectronmicroscope,X-rayphotoelectronspectroscopy,X-rayDiffraction,
Ramanspectroscopyandelementalanalysis.ResultsshowthatM40Jfiberhasahighercarboncontent,lessnitrogenand
lesssurfaceactivecomponentincomparisonwithT300fiber.ThesurfaceofM40JandT300carbonfibershasmanygrooves,
longerandshallowerforM40J,shorteranddeeperforT300.T300carbonfibershowsanobvioussheath-corestructure,while M40Jshowshomogeneousstructures.ThecrystallitestructureandorientationofM40Jcarbonfiberisbetterincomparison withT300carbonfibers.

Abstract:AstudyofimageprocessinganddataanalysisofSEM micrographsofthreekindsofcarbonfibersamples wasdescribedinthispaper.ImageprocessingsoftwareincludingImageProPlus,MatlabandPhotoshopwasemployedto studythesectionpatternsofcarbonfibersaswellasquantitativelyanalyzeandcontrasttheirroundness(α)anddiameter.TheroundnessesofGCF-1,GCF-2andT300are0.980,0.809and0.846respectively.Byusingthismethod,thephysical propertiesofcarbonfiber’ssurfacecanbequantitativelycharacterized.

Abstract:C/Ccompositeswithrefractorymetalcompoundswerepreparedbyliquidimpregnation,the distributionstateofrefractorymetalgrainwasobservedbyopticalmicroscopeandsurfacescan.Microstructuremorphologyofcarbonfibers,carbonmatrixandfiber/matrixinterfaceweremeasuredbyscanelectron microscope,transmissionelectronmicroscopeandopticalmicroscope.

Abstract:ByimprovingtestingprincipleandtestingtongsinQJ3074—1998,,thetestingaccuracyof fourprobemethodforelectricresistivityofwirematerialswasraisedandthetestingscopewaswidened.Throughtheexperimentsoftheeffectofsamplelengthandtestingconditionsonthetestingresults,theelectricresistivityofvariouscarbonfibersischaracterizedsystematicallyandthatlaidanimportanttechnical foundationforestablishingstandardofthetestingmethodofelectricresistivityforcarbonfibers.

Abstract:In this paper, the recent research progress in self-healing polymeric composites is introduced, as well
as the self-healing mechanisms of microcapsule, hollow fibers and vascular networks self-healing models are discussed. Finally the research trends of polymeric self-healing composites are proposed.