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79 个结果
  • 简介:ThisworkstudiedthecharacteristicsofSiO2distributionandstructureofsilicatephasesinMgO-ZrO2compositessynthesizedbyrawmaterialsoflightfiredmagnesitendzircon,Theresultsindicatethat30wt%-40wt%SiO2contentinthesystemisexistedintheformofcrystallineofforsterite(M2S),theremainderingofSiOcontent(60wt%0-70wt%)isexistedintheglassphase,Thechemicalcompositionofglassphaseiswellagreedwiththechemicalcompositionofmonticellite(CMS).

  • 标签: 二氧化硅 氧化镁 氧化锆 复合耐火材料 硅酸盐
  • 简介:AnO'-Sialon-Al2O3compositerefractorywaspreparedbyinsitureactionofSi3N4-ZrSiO4-Al2O3mixturewithfusedaluminaaggregates.Densification,insitureactionprocedureandmicrostructureofthematerialwereinvestigatedbymeansofX-raydiffraction,opticalandscanningelectronicmicroscopesandEDAX.

  • 标签: O′-硅铝氧氮聚合材料 氧化锆 三氧化二铝 AL2O3 SIO2 ZRO2
  • 简介:β-sialon/alumina/silicamixturesweresinteredinflowingnitrogenat1500℃and1600℃respectively.ThesinteringpropertiesandmorphologyofsampleswereinvestigatedbySEM,EDSandXRD.Resultsshowthatsinteredpropertiesofthesamplesareinfluencedbysoakingtemperaturesandcompositions.Bulkdensitiesofsamplesareincreasedwiththeincreaseofthesoakingtemperature,whereastheapparentporositiesaredecreased.Masslossofthesinteredsamplesat1500℃islowerthanthatat1600℃,butallthemasslossremainsapproximatelyconstantwiththeincreaseofsialoncontent.Fromthepointofthermodynamicanalysis,ComplexchemicalreactionstakeplaceinsamplesduringsinteringprocessandthevolatileofSiO(g)isresponsibleforthemasslossofsamples.Comparedtocrosssectionmicrostructureofβ-sialon/Al2O3/SiO2mixturessinteredincokepowderbedconsistingofthedensecenterwithwell-developedcolumnofsialonphase,thetransitionalpartwithneedlelikegrainnitrogen-containingphaseandtheloosepartwithshortgranularAl2O3phase,thoseofmixturessinteredinflowingnitrogenisofwell-developedsialonindensecenterandslightlyloosepartwithsialondebris.

  • 标签: 硅铝氧氮聚合材料 氧化铝 硅石 高温条件 耐火材料
  • 简介:MicrostructureandgrainboundarycharacterofhotpressedbinaryAl2O3(mullite,ZrO2)-SiCompositesandquaternaryAl2O3-mullite-ZrO2-SiCcompositewerestudiedbyelectronmicroscopyandmicroanalysis,ResultssuggestthatthereexistgrainboundarysolidsolutionsduetoelementaldiffusionnearSiCandmatrixoxidesgrainboundaries.

  • 标签: 微观结构 氧化铝 AL2O3 ZRO2 碳化硅 氧化锆
  • 简介:LowcementAl2O3-SiO2castableswaspreparedusingsupergradebauxite(w(Al2O3)>85%)asaggregate,brownfusedcorundum,siliconcarbide,Secar71CAcement,α-Al2O3micropowderandmicrosilicaasfinepowders.TheinfluenceofSiC(0,5wt%,10wt%,and15wt%)onresistancetoPbO-richslagwasinvestigatedbystaticcrucibleslagtest(1300℃for5h,inair).TheslagcorrosionmechanismofthecastableswasanalyzedbymeansofSEM,EDSandXRD.TheresultsshowthattheresistanceofAl2O3-SiO2castablestoPbO-richslagisimprovedobviouslybytheadditionofSiC.ThecorrosionmechanismofthePbO-richslagcanbediscribedasthatPbOintheslagreactswithSiO2andCaOinAl2O3-SiO2castables,forminglow-meltingcompounds(suchasPbO·SiO2and2PbO·SiO2).

  • 标签: 二氧化硅 氧化铝 硅含量 氧化铅 碳化 料渣
  • 简介:MgO-Al2O3-Cr2O3rammingmixesmadeofdifferentrawmaterialshavedifferentmineralstructureanddifferentphysicalpropertiesthoughwiththeidenticalparticlesizedistribution,thesameamountofbinderandchemicalcomposition.Theresidualcarboncontentofthefusedmagnesia-chromematerialmadeinreducingatmosphereisveryhigh,ifthismaterialsisusedintheMgO-Al2O3-Cr2O3rammingmix,itwouldcausespallingofthefurnaceliningduringdrying-out.

  • 标签: 原材料 氧化镁 三氧化二铬 搪炉料 搪包料 三氧化二铝
  • 简介:MgO-ZrO2unfiredbrickswithZrO2contentupto8%attheintervalof2%wereprepared,usingfusedmagnesia(MgO:97%)andfusedMgO-ZrO2clinker(ZrO2:14.33%)asstartingmaterialsandphenolicresinasbinder.TheeffectsofZrO2contentonthermalshockresistance(TSR)andotherpropertiessuchascoldandhotmodulusofrupturehavebeeninvestigated.Residualcoldmodulusofruptureratioafterheatingat1000℃andquenchingbyairblowingwasadoptedtocharacterizeTSR.AdditionoftheMgO-ZrO2clinkerimprovesTSR,attributingtothemicrocracktougheningeffectbythermalexpansionmismatchbetweendifferentphases.WhenZrO2contentgoesabove4%,theimprovingeffecttendstobemoderate.TheintroductionofMgO-ZrO2clinkercanalsoimprovetheHMORat1500℃,whiletheincreasedZrO2contentreducesCMORofthebricksprefiredat1600℃,duetothethermalexpansionmismatcheffect.Compromisingtheoverallproperties,theoptimalZrO2contentforsuchmagnesiabasedunfiredbrickissuggestedtobe4%.

  • 标签: 氧化镁 氧化锆 防火砖 抗热震性
  • 简介:Thisworkinvestigatedthethermo-gravimetric(TG)changeandexplosionresistanceofultra-lowcementAl2O3-SiO2castablesaddedwith0,5%,10%,15%and20%of≤74μmrawbauxitepowderscontaining72.8%Al2O3,respectively.Thecastableswerepreparedusingwhitefusedaluminaasaggregate,powdersofwhitefusedalumina,fusedmullite,α-Al2O3ultrafines,3%CAcementand5%microsilicaasthematrixportion.TGchangeofthecastableswasinvestigatedbyathermo-gravimetricanalyzerforlargesizespecimen.Whentherawbauxiteadditionislessthan10%,themass-losingbehaviorofthecastablesissimilartothatwithoutrawbauxite,tendingtoreachaconstantmassaround400℃,beforewhichthemass-lossismildandproducinglittledestructiveinfluence.Withmorethan10%rawbauxiteaddition,however,themass-lossincreasessignificantly,andthetemperaturetoreachaconstantmassincreasesto600℃orhigher,unfavorabletostructuralstabilization.Withtherawbauxiteadditionupto20%,nonegativeinfluenceonexplosionresistanceisfound.

  • 标签: 氧化铝微粉 铝土矿石 超低水泥 二氧化硅 浇注料 热行为
  • 简介:SlagcorrosionresistanceofMgOZrO2refractorieswasinvestigatedinthiswork.Theresultsindicatethatinanon-orientedelectricsteelslagsystemwithahighratioofcalciatosilica,theslagresistanceofMgOZrO2refractoriescanbedescribedasfollows:ZrO2reactswithCaOformingcalciumzirconatecompoundwhichstrengthensthematerialandblocksthechanneloftheslaginfiltration;however,inanorientedelectricsteelslagsystemwithahighconcentrationofsilicaandthelowratioofcalciatosilica,theslagcorrosionresistanceofMgOZrO2refractoriesisdifferent;ZrO2reactswithCaOformingthecalciumzirconateandsimultaneouslyonemoreproductC2Saswell;C2Scanimprovecorrosionresistancebyblindingporeandenhancingslagviscosity;therefore,itisexpectedtobethemajorreasonfortheenhancedcorrosionresistanceobservedforMgOZrO2refractories.

  • 标签: 耐腐蚀性能 耐火材料 氧化锆 氧化镁 二氧化硅 炉渣粘度
  • 简介:Reactionsintereddensezirconia-mullitecompositeswerepreparedbyisostaticallypressingfromzirconflourandreactivealuminawithdifferentproportionsofTiO2andCr2O3additives.Thepressedcompactsweresinteredatdifferentelevatedtemperatureswithvariablesoakingtimes.Microstructuresandphasedevelopmentinthesinteredcompactswereanalysedtoassesstheinfluenceoftheadditivesonthepropertiesofthezirconiamullitecomposite.

  • 标签: REACTION SINTERING ZIRCONIA-MULLITE ADDITIVES microstructure isostatic
  • 简介:ThepaperdescribestheeffectofadditivesAl,Si,SiCandB4ContheexpansionofMgO-ZrO2-Cmaterialafterbeingcoked.TheresultsindicatethatAlandSicannotincreaseitshotandcoldstrength.AlandSiwereoxidizedtoformAl2O3andSiO2respectively,andthenreactedwithCaZrO3orstabilizerinc-ZrO2toformcalciumaluminate,spinel(MA),dicalciumsilicate(C2S)andforsterite(M2S).Meanwhile,α-C2Swastransformedtoγ-C2Sandc-ZrO2tom-ZrO2whentemperaturechanged.AlltheabovereactionsresultedinthedecreaseoftheamountofAl4C3andSiCandtheincreaseinbulkvolume,whichcausedthestructureofMgO-ZrO2-Cmaterialdestroyed.Hence,contrarytotheMgO-Cmaterial,whenaddingAl.andSi,theMgO-ZrO2-Cmaterialwouldbestructurallydeterioratedafterheat-treatmentanditsstrengthandcorrosionresistancedecreased.

  • 标签: 性质 氧化镁 MGO 二氧化锆 ZRO2
  • 简介:Theprinciplesandfeaturesofmicrowavesintering,theapplicationinrefractoriesandsynthesismethodsofZrB2arereviewed.ThesynthesisresultsofZrB2bythermitdeoxidatemethodshowthatproductionpriceofZrB2canbeeffectivelyloweredthroughmicrowavesynthesis.ItwillexpandtheapplicationofZrB2inrefractories.

  • 标签: 微波烧结技术 耐火材料 合成方法
  • 简介:TherearemanyprocessestoproduceCr2O3fromchrome-ores,DifferentparticlesizerangesofCr2O3powder,finepinmentgradegreenCr2O3andcoarsemetallurgygradeblackCr2O3,aremadebydifferentprocessesinChina,GreenCr2O3assuperfineandadditionandmetallurgygradeblackCr2O3usedtosynthesizeCr2O3graincanbeappliedtorefractories.ItisverydifficultforhighpurityCr2O3tosintertodensificationandTiO2additioniscontributedtodensificationofCr2O3sinteredathightemperature,Cr2O3grainswithrelativedensityof91%-95%aregainedbysinteringCr2O3withTiO2additionandelectrofusingCr2O3rawmaterials.

  • 标签: 三氧化二铬 CR2O3 原料 耐火材料
  • 简介:AkindofZrO2ceramicmaterialforporousmediaburnerwaspreparedbypolymericspongeprocesswithstartingmaterialsofzircon,zirconiapowder,microsilica,andballclay,andbinderofsilicasolthroughreaction-sintering.Theeffectsofmicrosilicaadditiononcoldcrushingstrengthandzirconia/zirconaddingratioonthermalshockresistancewerestudied.Theresultsshowthattheporousmediamaterialhasproperporosity,highstrength,andexcellentthermalshockresistancewhenzirconiaadditionis85%andzirconadditionis5%.Theperformanceindexesare:porosity82%,coldcrushingstrength3.1MPa,thermalshockresistancemorethan10cycles,andgoodthermalshockresistanceto1500℃flame.

  • 标签: 氧化锆陶瓷材料 多孔介质 性能指标 燃烧器 抗热震性 起始原料
  • 简介:Inthis,phasecompsitionandthermalexpansionbehaviourofCaOStabilisedrefractorieswerestudied,Specialattentionwaspaidtotheexpasionbehaviourofthreematerialswithdifferentphasecomposition,TheresearchresultsindicatedthattheexpansionbehaviourcouldbeimprovedbymodifyingthestabilizationofZrO2,whichthusleadstotheincreaseinthethermalshockresistanceandpossiblyeroionresistaceofas-obtainedCaOstabilisedZrOmaterial.

  • 标签: 热膨胀 相组成 二氧化锆 耐火材料 氧化钙