简介：Oxidationprocessoflanthanumhexaboride(LaB6)ceramicpowderwasinvestigated.TheLaB6powdersampleswereheatedcontinuallyfromroomtemperatureto1473Kataheatingrateof10K/minbydifferentialscanningcalorimetry.Theoxidationtestswereconductedatdifferentexposuretemperatures.ThephasesandmorphologiesofthesamplesbeforeandafterexposurewereanalyzedbyXRDandSEM.Itwaspointedoutthatbefore1273K,LaB6hashighoxidationresistantability,whichwasduetothattheoxidelayerhinderstheoxygendiffusionfromoutertothesurfaceofLaB6grains.Theoxidelayerwascomposedofthetransitionphases,whichwerecomposedofLa2O3andB2O3formedfromtheinitialoxidation;whentheoxidationtemperatureexceeded1273K,protectivelayerwasdestroyedduetothevaporizationofliquidB2O3.BasedontheresultsofX-raydiffractionanalysis,oxidationprocessofLaB6ceramicpowdercanbedescribedasfollows:Before1273K,lanthanumborate，La(BO2)3wasformedonthesurfaceofsamples,thenlanthanumoxide(La2O3)andboronoxide(B2O3)werepresentonthesurfaceofsamplesoxidizedwhenthetemperaturereachedto1473K.

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简介：Compressedthinlayersofceramicfiberinsulationareusedashightemperatureinsulatinglayersaswellasmechanicalsupportforcatalystcoatedceramicmonolithsinautomotiveemissioncontroldevices.Minimizationofenergylosses,choiceofmaterialandthicknessofcompressedinsulatinglayerarebasedonknowledgeoftheirthermalphysicalproperties.Currently,consistentmeasurementsofmaterialsinacompressedstate,astheywouldbeinemissioncontrolapplications,areabsentduetotheabsenceofsuitablemethodsforsuchtests.Atestmethodwasdevelopedformeasurementofthethermalconductivityofcompressedthinfiberlayers.Thispapersummarizestheresultsofthermalconductivityanddiffusivitymeasurementsof27compressedfiberalumina-silica-vermiculitematerialsintherangeof200-950℃.Thermalphysicalpropertiesasafunctionoftemperature,density/mechanicalpressure,thicknessandcompositionofinsulatinglayersarepresented.Thewholesetofexperimentaldataisgeneralizedon3Dsurfaceplotsanddescribedbypolynomialfunctions.Thepossibleheattransfermechanismsgoverningapparentthermalconductivityofpressedinsulationlayersarediscussed.

简介：TransparentYAG(yttriumaluminumgarnet)ceramicswerefabricatedbysolid-statereactionmethod.Effectofadditive(tetraethylorthosilicate,TEOS)onmicrostructureofYAGceramicswasinvestigated.IftheadditionofTEOSismorethan3%(massfraction),largeamountofliquidphasecanbeyieldedatgrainboundaries,resultingintheformationofsecondphaseparticlesatgrainboundaries.Iftheadditionislessthan0.05%(massfraction),poresareentrappedinthegrains.Thesuitableamountis0.5%(massfraction).AfullytransparentYAGceramicwasfabricatedbyvacuumsinteringat1700℃for5h.OpticaltransmittanceoftheYAGceramicis63%inthevisiblelightwavelengthsand70%intheinfraredwavelengths.

简介：Mechanicalandelectricaldamagesareintroducedtostudythefracturemechanicsofpiezoelectricceramicsinthispaper.Twokindsofpiezoelectricfracturecriteriaareestablishedusingthemethodofleastsquarescombinedwithadamageanalysisofthewell-knownpiezoelectricfractureexperimentsofParkandSun's.Oneisbasedonalinearcombinationofthemechanicalandelectricaldamagesandtheotherontheirnonlinearcombination.WhenthecombineddamageDisuptoitscriticalvalueDc,piezoelectricfractureoccurs.Itisfoundfromthequalitativecomparisonofthenumericalresultswiththeexperimentaldatathatthenonlinearlycombineddamagefracturecriterioncangiveabetterpredictionofpiezoelectricfracture.Anditisconcludedfromthenonlinearlycombineddamagefracturecriterionthatanegativeelectricfieldimpedesfracturewhereastheeffectofapositiveelectricfieldonfracturedependsonitsmagnitude.

简介：ThefracturetoughnessofMgOpartiallystabilizedzirconia(MgO-PSZ)hasbeenmea-suredbythehardnessindentationmethod.TheinfluencesofheattreatmentonthefracturetoughnessK1cofMgO-PSZwerestudied,ItwasfoundthatthefracturetoughnessofMgO-PSZcanbegreatlychangedbydifferentheattreatmentprofile.Thefracturetoughnesswasimprovedbytheheattreatmentat1100℃afteragingat1400℃,TherewasthegreatestK1cvalue(11.30MPa.m^1/2)ofthesamplesagedat1400℃for2hfollowedbyasubse-quentannealat1100℃for10h.ThechangesinthemicrostructureofMgO-PSZceramicsagedwithdifferentthermaltreatmentwerestudieddbyuseoftransmissionelectronmicroscopy.

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简介：Ceramics,Pottery.Stoneware.Earthenware这是一组有关"陶瓷"的词。几乎所有英汉词典和英汉美术词典都把这四个词解释为:ceramics(总称)陶器;pottery(集合词)陶器类、陶器(总称):stoneware缸器粗陶(器):earthenware(集合词)陶器。1.按照上述解释,除stoneware外,其余三个词皆为陶器,这三个词之间有什么联系?有什么不同呢?它们所指的是否是同种东西?

简介：Basedonshearlagmodelofinterfacebetweenfiberandmatrix,anewformulathatre-latesthecrackopeningdisplacementandbridgingforceinfibrousmonolithicceramicswasconstructedundertheframeworkofsmallscalebridging.Thisformulawasappliedtopredictthefractureresis-tanceorR-curveresponseofathree-pointbendingspecimenmadeoffibrousmonolithicceramics.Aparametricinvestigationontheinfluencesoffibervolumefraction,fiberradius,characteristicsofconstituents,BN’sfracturetoughnessandspecimen’sgeometryonthebridgingforcesandfracturere-sistanceinSi3N4/BNcompositewascarriedout.TheupperandlowerlimitsoftheR-curveofSi3N4/BNinsmallscalebridgingwerederived,Thisresearchrevealedtheroleplayedbytheaboveparame-tersinthefracturetoughnessoffibrousmonolithicceramics.

简介：Recentprogressonrare-earthdopedpolycrystallineYAGtransparentceramicshasmadethemanalternativenovelsolid-statelasergainmaterial.Inthispaper,wepresentresultsofourresearchonpolycrystallineRE:YAGtransparentceramics.HighopticalqualityYAGceramicsdopedwithvariousrare-earth(RE)ionssuchasNd3+,Yb3+,Er3+,Tm3+,andHo3+havebeensuccessfullyfabricatedusingthesolid-statereactivesinteringmethod.Highlyefficientlaseroscillationsofthefabricatedceramicsaredemonstrated.

简介：以便讨论修改La的铅锆酸盐titanate锡酸盐antiferroelectric陶艺PbLaZr的非线性的机电的性质，Sn，TiO3PLZST，近似线性化的电致伸缩的方程古典线性压电的方程从秒顺序被导出的一模一样的形式概括压电的方程称为。解决非线性的antiferroelectric阶段转变陶艺变换器的电声的transduction问题的一条分析途径被介绍。PLZST的非线性的性质能基于为分析变换器的电声的transduction问题的近似线性化的电致伸缩的方程与维持的偏爱是线性地相等的。创新antiferroelectric陶艺有回声频率1.1kHz的低频率班IVflextensional变换器基于途径被开发它作为活跃元素利用PLZST。湖认证显示为变换器的PLZST的使用一会儿在它的PZT-4对应物上在在SL的TVR和9dB增加产出3dB增加，并且途径是有效的。

简介：Yttriumaluminumgarnet(YAG)transparentceramicswerefabricatedbysinteringatoxygenatmosphere.Tetraethylorthosilicate(TEOS)wasaddedasthesinteringadditivetocontrolthegraingrowthanddensification.Poreswereeliminatedclearlyattemperaturelowerthan1700oC,whilegrainsizewasaround3μm.Thein-linetransmittancewas80%at1064nmwhensamplesweresinteredat1710oC.TheeffectofTEOSwasstudiedinoxygenatmospheresinteringforNd:YAGtransparentceramics.Athighertemperaturelike1710oC,thegraingrowthmechanismwassolutedrag,whileat1630and1550oCthegraingrowthwascontrolledbyliquidphasesinteringmechanism.And0.5wt.%TEOSwasthebestaddingcontentforNd:YAGsinteredinoxygenatmosphere.

简介：Itisexpectedthatinthenewcentury,tocopewithdevelopmentsofnewhightemperaturetechnologies,anewgenerationofhighperformancerefractoryceramicswillemergeandflourishwhichshouldincludethefollowing(1)oxideandnonoxidecompositescharacterizedbyauniquecombinationofhighhotstrength,highthermalshockresistanceandhighcorrosionresistance;(2)freeCaObearingbasicrefractoriescapableofpurifyingmoltenmetalforimprovingcleanlinessandofabsorbingcontaminantsfromwastegasesforreducingenvironmentalpollution;(3)freeflowingzerocementcastableswithimprovedthermomechanicalproperties,thermalshockresistanceandcorrosionresistanceandgradientcastableswithvaryingmatrixcompositionandvaryingtexture.

简介：堇青石蜂房陶艺与1.5MHNO_3被对待，在93degC与1.5MNaOH列在后面有碱处理的酸处理的联合显著地减少了热扩大(CTE)的系数反弹由热处理引起了，在完全与酸对待的样品观察的现象。诱导地联合的血浆(ICP)分析结果表明碱处理优先地溶解了在acid-treatedsamples离开的“免费”的SiO_2，它为反弹的CTE被认为是一个关键因素负责。

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简介：ZhengzhouUniversityniversitiesinChinaandisoneofthenationalkeyuisjointlysupportedbytheMinistryofEducationandHenanProvincialGovernment.ItislocatedinZhengzhoucity,capitalofHenanprovinceincentralChinawhichisthecradleofChineseculture.Theuniversitycampuscoversanareaof4.3millionm2.Thereare40thousandundergraduateand3600post-graduatestudents.Itsceramicsdepartmentenrollsabout350students.

简介：Macroporoussiliconnitride(Si3N4)ceramicswithhighstrength,uniformstructureandrelativelyhighporositywereobtainedbygelcastingandcarbonthermalreactioninatwo-stepsinteringtechnique.Microstructureandcompositionwereinvestigatedbyscanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),X-raydiffraction(XRD).Openporosity,poresizedistributionandbasicmechanicalperformanceweremeasuredbyArchimedesmethod,mercuryintrusionporosimetryandthree-pointbendingmethods,respectively.SEMandTEMresultsrevealedthatporeswereformedbyelongatedβ-Si3N4.SADPmeasurementprovedtheformationofSiCparticles.TheSiCgranuleswerebeneficialfortheformationofhighratioelongatedβ-Si3N4,andatproperamount,theyalsoactedasreinforcementphase.Thermodynamicanalysisindicatedthatthemechanismsofthereactionsweremainlyassociatedwithliquid-solidreactionandgas-liquidreaction.

简介：Magnificent&GorgeousTheShanghaiCommunication&FinanceMansiondesignedbyWangShiwei,GeneralDesigner,wontheSpecialAwardinthe“2004DongpengInteriorDesigningCompetition”organizedbytheChinaConstruction&DecorationAssociation.

简介：DopedSrTiO3capacitor-varistormultifunctionalceramicswerefabricatedbyasinglesinteringprocess.ACcompleximpedanceanalysiswasperformedtoinvestigateelectricalfeaturesofgrainsandgrainboundariesforbothas-reducedceramicandreoxidizedceramics.Theresultsshowedthattheas-reducedceramicexhibitedinductiveresponseathighfrequenciesabove2MHz,whichisattributedtothecontributionofelectronbehaviorinsemiconductinggrains.Thehighfrequencyinductiveresponsedisappearedinimpedanceplotsofreoxidizedceramics.

简介：以便在oxyfluoride眼镜和玻璃陶艺的形成上调查不同重金属离子的影响，有不同PbF2/CdF2比率的样品被融化熄灭和热处理方法准备了。玻璃网络结构上的Pb2+和Cd2+的不同效果被FTIR和拉曼系列调查。在玻璃网络结构的形成期间，Pb2+喜欢打破Si–O–Si契约并且随后为起诉赔偿结合到F−，并且Cd2+喜欢打破Si–O–Al契约并且被O2−包围。Pb2+和F−一起聚在一起并且形成氟化物nanocrystals，当Cd2+在热处理以后留在氧化物矩阵时。合适的CdF2的介绍是重要的在透明玻璃陶艺的制造调整并且控制玻璃网络结构和结晶化过程。