Compound effect

Averageeffect

Itisthemosttypicalcompositeeffectdisplayedbycompositematerials.Itcanbeexpressedas:

Intheformula,Pisthematerialperformance,Visthematerialvolumecontent,andthesubscriptsc,m,andfrepresentcompositematerials,matrixandreinforcement(orfunctionalbodies),respectively.Somefunctionalpropertiesofcompositematerials,suchaselectricalconductivity,thermalconductivity,densityandelasticmodulus,obeythelawofaverageeffect.Forexample,iftheelasticmodulusofacompositematerialisexpressedbythemixingratio,itisacompositematerialwhoseparalleleffectshowsthiseffect.EachcomponentmaterialofthecompositematerialretainsitsownThereisneitherrestrictionnorcompensation.Forcompositematerialswherethereinforcement(suchasfiber)andthematrixinterfaceareweaklybonded,thecompositeeffectdisplayedcanberegardedasaparalleleffect.

ComplementaryeffectThematrixandreinforcementthatmakeupthecompositematerialcomplementeachotherinperformance,therebyimprovingtheoverallperformance,andshowacomplementaryeffect.

CompetitiveeffectWhenthematrixandreinforcementformacompositematerial,ifthepropertiesofthecomponentsrestricteachotherandlimittheimprovementoftheoverallperformance,thecompositeshowsacounteracteffect.

Inglassfiberreinforcedplastics,whenthesurfaceoftheglassfiberistreatedwithasuitablesilanecouplingagent,thecompositematerialcomposedoftheresinmatrixstrengthensthebondingoftheinterface,resultinginthetensilestrengthofthematerialComparedwiththecompositematerialcomposedofuntreatedfibers,itcanbe30-40%higher,andthewetstrengthretentionrateisalsosignificantlyimproved.However,thisstronglybondedinterfacealsoleadstoareductionintheimpactperformanceofthecompositematerial.

Therefore,inmetal-basedandceramic-basedreinforcedcomposites,excessiveinterfacialbondingmaynotbethemostappropriate.Complementaryeffectsandoffseteffectsoftencoexist.

Obviously,thecomplementaryeffectisdesired,andtheoffseteffectshouldbeavoidedasmuchaspossible.

Allthesecanbeachievedthroughthedesignofcorrespondingcompositematerials.

Thepressuresensitivityofcarbonfibercement-basedcompositesisaffectedbymanyfactors,anditspressuresensitivitymechanismisverycomplicated.Theinterfaceofcarbonfibercement-basedcompositematerialisabridgebetweencarbonfiberandcementmatrixtotransferstressandotherinformation.Theperformanceoftheinterfacedirectlyaffectsthecomprehensiveperformanceofthecompositematerialandplaysanimportantroleinthepressuresensitivityofthematerial.FundedbytheNationalNaturalScienceFoundationofChina,basedonexistingresearch,startingfromtheinterfacialpropertiesofcarbonfibercement-basedcomposites,theeffectofcarbonfibersurfacetreatmentonthepressuresensitivityofthematerialisstudied,andtheinterfacialpropertiesofcarbonfibercement-basedcompositesarestudied.Theeffectonthepressuresensitivityofmaterialsandthemechanismofaction.Thespecificworkandresearchresultsareasfollows:(1)Theeffectandmechanismofdifferentcarbonfibersurfacetreatmentsonthepressuresensitivityofcarbonfibercement-basedcompositesarestudied.Thecarbonfiber-cementmatrixwithoutsurfacetreatmenthaslowbondingstrengthandiseasytodebond.Theincreaseofvariousoxygen-containingpolargroupsonthesurfaceofthesurface-treatedfiberisconducivetotheformationofchemicalbonds,andimprovesthebondingstrengthandtoughnessoftheinterface,therebyimprovingthereliabilityandrepeatabilityofthematerial'spressuresensitivity.[Ⅰ]

Non-lineareffectsincludeproducteffects,systemeffects,inductioneffectsandresonanceeffects,someofwhichhavebeenrecognizedandused,andprovideagreatdegreeoffreedomforthedesignoffunctionalcompositematerials;andSomeeffectshavenotyetbeenfullyunderstoodandutilized.

MultiplyingeffectWhentwomaterialswithconversioneffectsarecombinedtogether,themultiplyingeffectcanoccur.

Forexample,whenmaterialswithelectromagneticeffectsarecombinedwithmaterialswithmagneto-opticaleffects,compositematerialswithelectro-opticaleffectsmaybeproduced.

Therefore,itisusuallypossibletocombineafunctionalmaterialX/YwithtwokindsofperformancemutualconversionandanotherkindofenergyconversionmaterialY/Z,whichcanbeexpressedbythefollowinggeneralformula,namely:

Intheformula,X,Y,andZrespectivelyrepresentvariousphysicalproperties.Theaboveformulaconformstotheproductexpression,soitiscalledthemultiplicationeffect.

AphasepropertyX/Y

B-phasepropertyY/Z

Productpropertyaftercompounding

(X/Y)(Y/Z)=X/Z

piezomagneticeffect

piezomagneticeffect

piezoelectricEffect

Magnetostrictiveeffect

Photoguideeffect

Scintillationeffect

Thermaldeformationeffect

Magneticresistanceeffect

Magnetoelectriceffect

Electroluminescenceeffect

Piezoresistiveeffect

Electro-inducedeffect

Photoconductiveeffect

Varistoreffect

Vistoreffect

Piezoelectriceffect

Pressureluminescenceeffect

Magnetoresistanceeffect

Photostriction

Radiation-inducedconductivity

Thermistoreffect

Themagnetoelectriccouplingeffectiswhenthematerialisinanexternalmagneticfield,itcanproduceelectricpolarization,orappearundertheconditionofanelectricfieldThephenomenonofmagnetization.Earlyresearchmainlyfocusedonsingle-phasecompoundswithmagnetoelectriceffect.However,themagnetoelectriceffectofsingle-phasematerialsisverysmallandcanonlyberealizedatlowtemperatures,soitcannotbeappliedinpractice.NanCewenetal.Thecompositematerialformedbythecombinationofthetwomaterialsoftheeffectandthemagnetostrictionhasalargemagnetoelectriceffect.Theprincipleis:themagnetic-forceconversiongeneratedbythemagnetostrictivematerialandtheforce-electricconversiongeneratedbythepiezoelectricmaterialpassthroughtheinterfaceThestresstransferandcouplingeffectofthenewmagnetoelectriccouplingeffectisrealized.[Ⅱ]

Theleadzirconatetitanatepyroelectricceramicmaterialcanbedirectlyappliedtothermoelectricenergyconversionandinfrareddetection.FRL)2Thenon-linearpyroelectriceffectproducedintheferroelectrichightemperature(FRH)phasetransitionprocesscanreach10timesthatofthelinearpyroelectriceffect.Theuseofthenon-lineareffectcangreatlyimprovethethermoelectricconversionefficiencyanddetectionrate.Thesituationofiondiffusionunderthemethodisdifferent,andthenonlinearpyroelectriceffectalsohasitsowncharacteristics:materialspreparedinparallelhaveawidephasetransitiontemperaturerange,andthereisanonlinearpyroelectriceffectinthisrange;Thenon-linearpyroelectriceffectofthematerialpreparedinalaminatedmannerisgreatlyaffectedbythearrangementorderofthechemicalcomponents;whilethepyroelectricoutputofthesamplepreparedinamixedmannerduringthephasechangeprocessisrelativelybalanced,butthetemperaturewidthisrelativelylarge.narrow.【Ⅲ】

InductioneffectUndercertainconditions,onecomponentmaterialinthecompositematerialcanchangethestructureofanothercomponentmaterialthroughinduction,therebychangingtheoverallperformanceorproducingneweffects.

Thisinducedbehaviorhasbeenfoundinmanyexperimentsandalsofoundonbothsidesofthecompositeinterface.

Forexample,crystallinefiberreinforcementhasaneffectontheinducingcrystallizationoftheamorphousmatrixorthecrystalorientationofthecrystallinematrix.Incarbonfiber-reinforcednylonorpolypropylene,duetotheinducingeffectofthecarbonfibersurfaceonthematrix,thecrystalstateandquantityontheinterfacehavechanged,suchastransversetranscrystallization.Thiseffecthasaspecialeffectonnylonorpolypropylene..

ResonanceeffectTwoadjacentmaterialsundercertainconditionswillproducemechanicalorelectricalormagneticresonance.

Thenaturalfrequencyofcompositematerialscomposedofdifferentmaterialsisdifferentfromthenaturalfrequencyoftheoriginalcomponents.Whenthestructureofacertainpartofthecompositematerialchanges,thenaturalfrequencyofthecompositematerialwillalsochange.

Usingtheresonanceeffect,thenaturalfrequencyofthecompositematerialcanbechangedaccordingtotheexternalworkingfrequencytoavoidthedamagecausedbythematerialduringwork.Forabsorbingmaterials,thecompositefrequencycanalsobeadjustedaccordingtothefrequencycharacteristicsoftheexternalwavelengthtoachievethepurposeofabsorbingexternalwaves.

Systemeffectisacomplexeffectofmaterials.Themechanismofthiseffectisnotveryclear,buttheexistenceofthiseffecthasbeenfoundinactualphenomena.

Forexample,alternateThehardnessofthelaminatedcoatingisgreaterthanthehardnessoftheoriginalsinglecoatingandtheestimatedvalueaccordingtothelinearmixingratio,indicatingaphenomenonthatcanonlyoccurwhenacompositesystemisformed.

Averageeffect,multipliereffect,paralleleffect,inducedeffect,complementaryeffect,resonanceeffect,offseteffect,systemeffectandothercompositeeffectsarealltheobjectsandimportantcontentsofcompositematerialsscienceresearchThisisalsoabasictheoreticalissueforthedevelopmentofnewcompositematerials,especiallyfunctionalcompositematerials.

Thebiggestfeatureofcompositematerialsliesinitsdesignability.

Therefore,underthepremiseofgivenperformancerequirements,useenvironmentandeconomicconditions,designfromthewayofmaterialselectionandprocessstructure.

Forexample,usingthehybridlawoflineareffects,acomponentwithacoefficientofexpansionofzeroorclosetozeroinacertaintemperaturerangecanbedesignedthroughreasonablelaying.

AnotherexampleistheXYplaneispiezoelectric,andtheXZplaneshowselectroluminescence.TheYZplanepiezoluminescencecompositematerialcanbeobtainedthroughthelayerdesign.