简介:α-Fe^2O^3材料在陶瓷、催化剂、颜料、防腐、感光材料和磁性材料等方面都有着重要的应用,而且因其原料来源丰富、用途极广,因而受到格外关注。所以,均分散α-Fe^2O^3胶体粒子的制备,不仅在理论研究具有较高价值,而且在实际应用上也有重要意义。
简介:ThemechanicalpropertiesofpressurelesssinteringFe-Si3N4bondedSiCandSi3N4bondedSiCwithsamemanufactureprocesshavebeencomparedinthispaper.TheoxidizingmechanismofFe-Si3N4bondedSiCceramicmatrixcompositehasbeeninvestigatedespeciallythroughTG-DSC(thermogravimetricanalysis-differentialscanningcalorimeter)experiment.DuringoxidationprocedurethemainreactionistheoxidationofSiCandSi3N4,SiO2whichformprotectingfilmtopreventfurtheroxidizing.AndresidualironinthesamplesbecomeFe2O3andFe3O4,theoxidationkineticsat1100~1300℃ofre-Si3N4bondedSiChasbeenstudiedespecially.Theweightgainperunitareaatinitialstagechangesaccordingtobeelinerule,inthemiddleaccordingtoconic,andinthelastoxidationperiodfollowsparabolarule.
简介:AnO'-Sialon-Al2O3compositerefractorywaspreparedbyinsitureactionofSi3N4-ZrSiO4-Al2O3mixturewithfusedaluminaaggregates.Densification,insitureactionprocedureandmicrostructureofthematerialwereinvestigatedbymeansofX-raydiffraction,opticalandscanningelectronicmicroscopesandEDAX.
简介:MgO-Al2O3-Cr2O3rammingmixesmadeofdifferentrawmaterialshavedifferentmineralstructureanddifferentphysicalpropertiesthoughwiththeidenticalparticlesizedistribution,thesameamountofbinderandchemicalcomposition.Theresidualcarboncontentofthefusedmagnesia-chromematerialmadeinreducingatmosphereisveryhigh,ifthismaterialsisusedintheMgO-Al2O3-Cr2O3rammingmix,itwouldcausespallingofthefurnaceliningduringdrying-out.
简介:采用Nb2O3、Y2O3复合稳定剂,制得了高韧性、高强度的四方相ZrO2陶瓷材料,发现在Y2O3-ZrO2材料中加入0.5~1molNb2O3,可使材料在保持原有抗弯强度的同时,一定程度上改善了断裂韧性和相组成。
简介:TherearemanyprocessestoproduceCr2O3fromchrome-ores,DifferentparticlesizerangesofCr2O3powder,finepinmentgradegreenCr2O3andcoarsemetallurgygradeblackCr2O3,aremadebydifferentprocessesinChina,GreenCr2O3assuperfineandadditionandmetallurgygradeblackCr2O3usedtosynthesizeCr2O3graincanbeappliedtorefractories.ItisverydifficultforhighpurityCr2O3tosintertodensificationandTiO2additioniscontributedtodensificationofCr2O3sinteredathightemperature,Cr2O3grainswithrelativedensityof91%-95%aregainedbysinteringCr2O3withTiO2additionandelectrofusingCr2O3rawmaterials.
简介:根据PrincipiaPartners今年早期的市场研究“高端应用色母料的机遇”,北美2004年对微球的需求估计已经超过2.5亿美元,到2009年为止每年的增长率超过10%。微球作为塑料、涂料和密封剂的填料已经使用了数十年。作为填料,它们是独一无二的。作为设计的产品,它们可以是不同的物质、粒径、强度、密度’和纯度。通常是由玻璃、塑料和陶土构成,也可以是煤灰、碳、石英、纤维素、二氧化硅甚至金属。微球可以是实心也可以是空心,直径1~300μm。因为它们是设计的,粒子的形状一致,粒径分布非常窄,是可以提供良好的填料填充和自由流动的产品。根据应用,原料类型和是否是实心和空心的不同,
简介:Themicrostructureandslagerosionfractaldimensionofreactioninterfaceofβ-Sialon-Al2O3brickusedin300MtironladleofBaosteelhavebeenstudiedbySEMandXRD.Theresultsindicatedthatβ-Sialon-Al2O3brickexhibitedexcellentslagresistance.Themainwearmechanismofβ-Sialon-Al2O3brickismainlyfromthespallingcausedbythermalmechanicalstressandattackedbyslagsecondly.
简介:TheinfluencesoffourkindsofadditivesaddedintothematrixofMgO-Al2O3unbunedproductswereinvestigated,TheresultsshowthatsampleswithproperMgO/Al2O3rationandproperadditionofCr2O3(2%-4%)havegoodthermalshockresistanceandslagcorrosionresistanceaswell,XRDandSEMdeterminationresultsindicatethatakindofcompoundspinel(Mg,Al,Cr)O4wasformedandthemicrostuctureofthesamplesaredenser.