简介：Theplasticload-bearingcapacityofductilecompositessuchasmetalmatrixcompositesisstudiedwithaninsightintothemicrostructures.Themacroscopicstrengthofacompositeisobtainedbycombiningthehomogenizationtheorywithstaticlimitanalysis,wherethetemperatureparametermethodisusedtoconstructtheself-equilibriumstressfield.Aninterfacefailuremodelisproposedtoaccountfortheeffectsoftheinterfaceonthefailureofcomposites.Thestaticlimitanalysiswiththefinite-elementmethodisthenformulatedasaconstrainednonlinearprogrammingproblem,whichissolvedbytheSequentialQuadraticProgramming(SQP)method.Finally,themacroscopictransversestrengthofperforatedmaterials,themacroscopictransverseandoff-axisstrengthoffiber-reinforcedcompositesareobtainedthroughnumericalcalculation.Thecomputationalresultsareingoodagreementwiththeexperimentaldata.

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简介：Poly(methylmethacrylate)(PMMA),usedasdenturebasematerialsinden-tistry,hassomeinherentdefects,suchaslowertoughnessorhigherbrittlenesswhichisoneofthemainreasonsofthefractureofdenturebaseinclinical.Therefore,manyscientistshavefocusedonhighimpactstrengthdenturebasematerials.Inthispa-per,usingMethylmethacrylate-butadiene-styrene(MBS)asareinforcementagent,

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简介：Athermodynamicequationofstate(EOS)isderivedtobeappropriateforinvestigatingthethermodynamicvariationsalongisobaricpathstopredictthecompressionbehaviourofporousmaterials.ThisEOSmodelistestedonporousiron,copper,leadandtungstenwithdifferentinitialdensities.ThecalculatedtemperatureandHugoniotareingoodagreementwiththecorrespondingexperimentalandtheoreticaldatapublishedpreviously.Itisinterestingthatthismodelcansatisfactorilypredicttheshockbehaviourofporousmaterialsoverawiderangeofporosityandpressure.

简介：Constitutiverelationsfornonlinear,isotropic,electroelasticsolidsquadraticinthefinitestraintensorandthereferentialelectricfieldarederivedfromthefullnonlinearitytheoryofelectroelasticitybytensorinvariants,whichcandescribethebehaviorofelectrostrictivematerials.Theequationsarelinearizedforsmall,dynamicfieldssuperposedonfinite,staticbiasedfields.Theselinearequationsareusedtostudyplanewavespropagatinginanelectroelasticbodyundervariousmechanicaland/orelectricbiasedfields.Itisshownthatthespeedoftheacousticwavesexhibitsastrongdependenceuponthosematerialparametersinthenonlinearconstitutiverelations.Experimentaldeterminationofthesematerialparametersusingthisdependenceisdiscussed.

简介：称片的方法被用来调查不同水泥(灰)浆的不饱和的水运输。锋利的弄湿前面存在在期间的试验性的结果表演浇运输，运输能被一个非线性的散开方程描述，；搬运有水的各种各样的规则材料满足的不同材料展览的系数。所有各种各样的水里的水泥(灰)浆的苍蝇灰减少运输系数的增加满足，甚至变化运输机制。

简介：Theliquidcrystalcompositematerialsconsistofmicrodroplersofliquidcrystalswhicharespontaneouslyformedinamatrixofapolymeratthetimeofitspolymerization.Thedirectorconfigurationinliquidcrystaldroplets.themodeloforientationofdroplets,andthecontrastratiosofacellareinvestigated.Dropletsize,spacinganddistributionarereadilycontrolledinthesematerialstoallowoptimizationofdisplaysbaseduponelectricallycontrolledlightscatteringfromtheliquidcrystaldroplets.Preliminaryexperimentalandtheoreticalstudiesofthelightscatteringandelectro-opticresponseofnewmaterialshowthatthesematerialscanoffernewfeaturessuitableforlargeareadisplaysandlightvalves.

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简介：Permanentmagneticmaterialscapableofoperatingathightemperatureupto500°Chavewidepotentialapplicationsinfieldssuchasaeronautics,space,andelectroniccars.SmCoalloysarecandidatesforhightemperatureapplications,sincetheyhavelargemagnetocrystallineanisotropyfield(6–30T),highCurietemperature(720–920°C),andlargeenergyproduct([200kJám-3)atroomtemperature.However,thehighestservicetemperatureofcommercial2:17typeSmComagnetsisonly300°C,andmanyeffortshavebeendevotedtodevelopnovelhightemperaturepermanentmagnets.ThisreviewfocusesonthedevelopmentofthreekindsofSmCobasedmagnets:2:17typeSmComagnets,nanocrystallineSmComagnets,andnanocompositeSmComagnets.Theoxidationprotection,includingalloyingandsurfacemodification,ofhightemperaturepermanentmagnetsisdiscussedaswell.

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简介：ForewordItiswellknownthatallelectricalmachinesandequipmentsaremademainlyofconductingmaterials,magneticmaterials,struc-turalmaterialsandinsulatingmaterials.Insulationmaterialsaresub-jectedtomechanical,thermalandelectricalstressesandexposedtomoisture,dirt,chemicalcorrosionandradiation.Thecombinedac-tion,intensityanddurationofsuchstressesandeffectssetalimitto

简介：Manybiologicalmaterials,suchaswoodandbone,possesshelicoidmicrostructuresatmicroscale,whichcanserveasreinforcingelementstotransferstressbetweencracksurfacesandimprovethefracturetoughnessoftheircomposites.Failureprocesses,suchasfiber/matrixinterfacedebondingandslidingassociatedwithpull-outofhelicalfibers,areresponsiblemainlyforthehighenergydissipationneededforthefracturetoughnessenhancement.Herewepresentsystemicanalysesofthepull-outbehaviorofahelicalfiberfromanelasticmatrixviathefiniteelementmethod(FEM)simulation,withimplicationsregardingtheunderlyingtougheningmechanismofhelicoidmicrostructures.Wefindthat,throughtheiruniformcurvatureandtorsion,helicalfiberscanprovidehighpull-outforceandlargeinterfaceareas,resultinginhighenergydissipationthataccounts,toalargeextent,forthehightoughnessofbiologicalmaterials.Thehelicityoffibershapeintermsofthehelicalanglehassignificanteffectsontheforce-displacementrelationshipsaswellasthecorrespondingenergydissipationduringfiberpull-out.

简介：Inordertoestimatetheerosionratesofsomeplasmafacingcomponentmaterials,thesputteringyieldsofMo,WandLibombardedbychargedparticlesH^+,D^+,T^+andHe^+arecalculatedbyapplicationofsputteringtheorybasedonbipartitionmodelofiontransport.ThecomparisonswithMonte-Carlocalculationresultsaremade.Thesedatamightbeusefultoestimatethelifetimeofplasmafacingcomponentsandtoanalyzetheimpuritylevelincoreplasmaoffusionreactors.

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简介：Theheatedprocessofrawmaterialsforelectrontrappingmaterials(ETM)isinvestigatedbythermo-analysismethod.Thetemperaturerangesofrawmaterialsexperiencedsomephysicalandchemicalchangeprocesses,suchasdehydration,organicsolventremoval,crystalsulphurburning,oxidationofalkalineearthsulfidesandsolidphasereaction(rareearthdoped)andsoon,areobtained.TheexperimentalresultsalsoshowthatthepresenceoftraceoxygeninshieldedgasisveryharmfultopreparetheETM.Therawmaterialthermo-analysisresultsprovideveryimportantexperimentalreferenceforoptimizingtheETMpreparationtechniques.

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简介：Thegrowthandcoalescenceoftwomicroholesincopperfoilwerestudiedexperimentallybyinsitutensiletestsundera,scanningelectronicmicroscope.Twomicroholesof15-35μmindi-ameterwerearrangedindifferentdistancesandorientations.Itwasfoundthatthemechanismsofmicroholeevolutionwererepresentedbyslippingbandcreation,andthencrackinitiationandpropagationalongtheslippingbands,inligament.Theprocessofmicroholegrowthandcoalescencewasinfluencedbytheinter-centerdistanceandorientationofmicroholes.Thecriticalsurfaceofmicroholesatcoales-cenceisabout2—2.5timesthatoftheinitialone.Thevariationofboththeintercenterdistanceandorientationdependsontheinitialangle.

简介：　　Thebonecompositewasproducedbybiomimeticsynthesis.Itshowssomefeaturesofnaturalboneinbothcompositionandmicrostructure.Andthecollagenmolecularsandthenano-crystalhydroxyapatiteassembleintoultrastructuresimilartonaturalbone.Itpossessesporousstructurewithporosityfrom100μmto500μmaftermixedwithPLA(polylacticacid).　　……