简介：Mullite-corundumbricksandkilnfurni-turewithhighcreepresistanceandgoodthermalshockresistancewerefabricatedbasedonlowcostrawmaterials,theapproachesofintroducingsomeadditivesandoptimisig,chemicalcompositionandparticalsizeweremployedtoproduceahightemperaturematrixphasewithhighcreepresistanceandgoodthermalshockresistance.

简介：1ScopeThisstandardspecifiesthetermsanddefinitions,theory,apparatus,specimens,testprocedures,calculationresults,apparatuscheckandtestreports,etc.ofabrasionresistanceatambienttemperatureofrefractoryproducts.Thisstandardisapplicabletodeterminetheabrasionresistanceatambienttemperatureofdenserefractoryproductsusedinerosionandcorrosionconditions.

简介：Inthiswork,thefactorsandparametersofatestmethodonabrasionresistanceatelevatedtemperatureswerediscussedandresearched.Firstofall,theprecisiontestsofthetestmethodonabrasionresistanceatelevatedtemperatureswereconductedin8laboratories.Theresultssuchasthestandarddeviationandreproducibilityshowgoodrepeatabilityandreliability.Therelationshipbetweenthestabilityofrefractoryperformanceandthestandarddeviationoftheirwearvaluewasanalyzed.ThentheimpactoftheheattreatmentconditionofunshapedrefractoriesandoxidationofSiCsandasabrasiveonthelostvolumeofthetestedspecimenswasresearched.

简介：Onthebasisofthetheoryofthermalshockresistanceinthescienceofmaterialsandthetestmethodofairquenchingwhichisgenerallyrec-ognizedinternationally,especiallyinEurope,thepresenttestmethodsfordeterminationofthermalshockresistanceinChinahavebeenanalysed,Experimentstudyonthermalshockresis-tanceofsilicaandbasicrefractoryproductshasbeenconducted,andanewtestmethodofthermalshockresistance-airquenchingmethodhasbeenputforward.

简介：SlagcorrosionresistanceofMgOZrO2refractorieswasinvestigatedinthiswork.Theresultsindicatethatinanon-orientedelectricsteelslagsystemwithahighratioofcalciatosilica,theslagresistanceofMgOZrO2refractoriescanbedescribedasfollows:ZrO2reactswithCaOformingcalciumzirconatecompoundwhichstrengthensthematerialandblocksthechanneloftheslaginfiltration;however,inanorientedelectricsteelslagsystemwithahighconcentrationofsilicaandthelowratioofcalciatosilica,theslagcorrosionresistanceofMgOZrO2refractoriesisdifferent;ZrO2reactswithCaOformingthecalciumzirconateandsimultaneouslyonemoreproductC2Saswell;C2Scanimprovecorrosionresistancebyblindingporeandenhancingslagviscosity;therefore,itisexpectedtobethemajorreasonfortheenhancedcorrosionresistanceobservedforMgOZrO2refractories.

简介：

简介：BycarbothermalreductionofMgOwithblackcarbonasreductionagentatahightemperature,MgOwasdepositedonthesurfaceofMgO-CaOclinker(ascoating)toimprovetheclinker'shydrationresistance.Inthepaper,effectofdepositiontemperatureandholdingtimeonthehydrationresistanceofthetreatedMgO-CaO,thedepositionmechanismandMgOcoatingkineticswereinvestigatedwithhydrationresistancetest,X-raydiffractometry(XRD)andscanningelectronicmicroscope(SEM).ResultsshowedMgOcoatinggrewina2DmodeonthesurfaceofMgO-CaOparticles;theMgOcoatingimprovedthehydrationresistanceofthecoatedMgO-CaOclinker,andthecoatedclinkerwouldbecomestrongerwhencoatedathigherdepositiontemperatureandlongerholdingtime.ThemeasurementsalsofoundthatMgOdepositionprocessvariedwiththedepositiontemperature:itwasmainlyachemical-controlledprocessattemperaturesbetween1400-1500℃,withanapparentactivationenergy(AAE)of97.8kJ·mol~(-1);itwouldchangeintoadiffusion-controlledprocesswhenthetemperaturerisingto1500-1600℃,withapparentactivationenergyof19.2kJ·mol~(-1).

简介：ThemagnesiabasedcurablespecimenswithdifferentSi3N4contentswerecastedusingsinteredmagnesite(w(MgO)=95%)asstartingmaterial,SiO2micro-powderasbinder,0.3%,4%and5%β-Si3N4powderreplacingtheequaladditionofmagnesiapowderrespectively.Theslagresistancetestwascarriedoutat1550℃for3husingBaosteeltundishslagandstaticcruciblemethod.Theresultindicatesthat:introducingSi3N4couldobviouslyimprovetheslagresistanceofMgObasedcastable,whichincreasedwithincreasingSi3N4.DenseSiO2sinteredlayerformedonthesurfaceofmagnesiabasedcastablebecauseoftheoxidationofSi3N4addition,whichcanpreventthefurtherslagpenetration.Inthedeepinnerofcastable,thepartial-pressureofoxygenwasverylow,soSi3N4canexiststably.Meanwhileinreducingatmosphere,Si3N4washardtobesintered,whichresultedinthelooseinteriorstructureofMgObasedcastable.

简介：Thermalshockresistantpropertiesofreactionsinteredbauxite-basedβ-Sialonbondedcorundumhavebeeninvestigated,andtheresultsarecomparedwiththoseofAl2O3basedcounterpart.Itisfoundtheyallhaveverygoodthermalshockresistance.Theirresidualstrengthratiosafteronethermalshockcycleat△T=1200℃and△T=1350℃are61%～73%and53%～65%respectively.Theircriticaltemperaturedifference(TSR)is600℃～800℃.TSRparametersarecalculatedbasedonthermalexpansion,modulusofelasticity,andfracturetoughnessdetermined.ThereasonsforimprovingTSRofthesecompositematerialsarediscussed.

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简介：Calciumhexaluminateisonefromsuchperspectivematerials.Itischaracterizedbyhighrefractoriness(above1830℃),aswellaspropertiesstabilityinreducingatmosphere,highalkali-andslag-resistance,lowthermalconductivityandwettabilitybymoltenmetals.Inthisworkinfluenceresearchesoffusedcalciumhexaluminatematerialadditiveinamountof5%,15%and25%onthemainpropertiesofaluminarefractorieswerecarriedout.Itisestablishedthat,therefractoriescontainingtheadditiveof25%calciumhexaluminatematerialarecharacterizedbythehighestproperties,slightlyimpregnatedwithmetalmeltandthehighestmetalcorrosionresistance.ThealuminapurgingplugsforblowingofmetalwithcalciumhexaluminatematerialadditiveareproducedandintendedtoonemetallurgicalplantofUkraineforcarryingouttests.

简介：

简介：Thekineticprocessofslagcorrosionforβ－Sialonandβ-Sialon-Al2O3compositeshasbeenstudiedbymeansofdipmethod(staticandself-rotating),Thecorrosionmodelisbuitlandtheformulaofcorrosionrateisdeduced,whichareinaccordancewithexperimentalresults.

简介：SiliconoxynitridewasaddedinshapedAl2O3-SiC-Crefractorymaterialtoimprovetheslagresistanceinthispaper.Optimumaddingquantityofsiliconoxynitridepowderwasalsostudied.TheresultsshowthattheslagresistanceofAl2O3-SiC-Cshapedrefractoryisimprovedwhen2%or3%Si2N2Oisadded.AreasonableamountofSi2N2OaddedintoAl2O3-SiC-Cshapedrefractorycanproducesiliconoxideintotheslag,whichcanimprovetheviscosityofslagandpreventtheslagerosionandpenetration.

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).

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%.

简介：Inthepresentpaper,novelsidewallmaterialsforaluminumreductioncellwerepreparedinairusingmagnesiaandmagnetiteasstartingmaterials.ThesinteringbehaviorsofthespecimenswereinvestigatedbymeansofX-raydiffraction(XRD)andscanningelectronmicroscope(SEM).AndcorrosiontestsinaNa_3AlF_6-AlF_3-K_3AlF_6bathwereconductedtoevaluatetheelectrolytecorrosionresistance.TheresultsshowthattheFe_3O_4phaseistransformedintoFe_2O_3athightemperatures,whichinturnreactswiththeMgOaddedtoformMgFe_2O_4spinel.AndwithincreasingtheMgOcontentfrom0to30mass%,densificationofthespecimensdecreasesmainlyduetolargervolumeexpansionresultingfromformationofmoreMgFe_2O_4.ThecorrosiontestsshowthatcorrosionlayersareproducedinalltheMgOaddedspecimens.However,forspecimenscontainingMgFe_2O_4phaseonly,Mg(Al,Fe)_2O_4compositespinellayersarealsogenerated,whichremarkablyimprovethecorrosionresistanceofthespecimens.