硅溶胶的胶团结构和干燥胶凝过程对硅溶胶型壳的几点认识之一13

©1994-2010ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.::TG249.5:A:1001-2249(2004)02-0052-031,,SiO230%,720nm1SiO2,Si-O-Si,Si-OH,,1(1),H3O+OH-,H3O+[1],H2OH2O+H2O=H3O++OH-(1)O2H,,105,,,H3O+,,H3O+,,,,,,,,H3O+,H3O+,,,23,110,140220,4007002[2],2,150,200,150200,,2,400,400700SiO233,,SiO2,,SiO2,,3,SiO230%,2520042X,,1939,,,(230051),:0551-3422865,E-mail:[e-mail]:2003-10-25©1994-2010ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.(DTA)(TG)[2]20nm,1684;14nm2476;10nm3664;8nm485241SiO230%(100%),20nm,59%;14nm,53%;10nm,45%;8nm,36%,341.2.,,,,w(SiO2)=30%,1.19g/cm3300(4#36s),7d,,1.20g/cm3,5%,14nm,10%,,,3540s(4#),300,w(SiO2)=30%,1416nm,3.43.6;810nm,2.93.1140,,,1m,d()12L,,d,,,,,,,,,,,,,SiO2,,SiO23,SiO2,,20nm,46%,14nm41%,10nm35%,8nm32%SiO2,w(SiO2)=30%,a,w(SiO2)=30%x,30/(100-x)=ax=100-30/a(2)(2)x,42:20nm,36%;14nm27%;10nm16%;8nm8%,41235X,..,2002©1994-2010ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.:A:1001-2249(2004)02-0054-01,,,,1,111213141,,,,(B)A,,,,,,,,(:)3,,1945,,41(741024),:0938-2786304:2003-10-24,4,,,,,,50%80%,,50%80%,140,,(3),Si-O-Si,5,,,,,,,,,(),,,,()5,,,,,,,1,..:,1983.2.().,1983(1):4753(:)4520042©1994-2010ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.(strength,loadeddeformationandpermeability)ofthereclaimedsilicasolmoldshellwereinvestigatedincomparisonwiththatofmolochitesilicasolmoldshell.Theresultsshowedthattheunbakedmoldshellwastecantbereclaimedandrecycleddirectlywhiletheusedbakedpouredmoldshellwastecanbereclaimedandrecycledforbackingmaterialsofthemoldshell.KeyWords:InvestmentCasting,SilicaSolMoldShell,Recla2mationandRecycleStructureofColloidAggregationinSilicSolSilicandItsColloidConcretionduringDryingOneofSomeKnowledgesonMold2ingShellwithSilicSolXuYunxiang(ChinaUniversityofScienceandTechnology,Hefei,China)LuRuiLiLei(PenglaiJinchuangInvestmentValveIndustryLimt.,Penglai,China)2004(2)5254AbstractStructureofcolloidaggregationinsilicsolwasintroduced.Thecolloidstructureconsistsofcolloidcore,absorbentlayeranddiffusionallayer.Moistureinsilicsoliscomposedoffreewater,ab2sorbentwaterandstructurewater.Water2lossrateandrangeofcol2loidconcretionzoneofsilicsolduringinitialcolloidconcretionwerecalculated.KeyWords:SilicSol,ColloidConcretion,Water2loss,Struc2tureofColloidAggregationImprovementofSodiumSilicateTechnologyandItsQualityControlJingZongliangLiangJiarong(GuangzhouJinhongIn2vestmentCastingLtd.,Guangzhou,China)2004(2)5556AbstractNow,sodiumsilicatebinderformoldshellmakinginin2vestmentcastingisstillwidelyused.Theimprovedtechnologyforpreventionfromsteelleakageinsmallholeandwashwaterinsur2facelayeraswellasforcontrollingtheshellqualityisfavorableforthecostdropofrawmaterialsandshortenedproductiveperiod.KeyWords:SodiumSilicateTechnoloqy,WaxPattern,Invest2mentCastingDevelopingStatusofEPCin2001-2002inNorthAmericaandEuropeYeShengpingWuZhichao(HuazhongUniversityofScienceandTechnology,Wuhan,China)2004(2):5759AbstractTherewere45reportsandthreehotpointsonthreeEPCsyposiumsheldinAmericaandGermanyin2001-2003:1.Re2searchoneliminationofcastingdefectsforAlalloy;2.Improvementofmoldingtoolandofpatternmakingblank;3.AnapproachtosimulationofEPCandrapidprototyping.Anintroductionofenter2priesestatusinEPCathomeandbroadwaslistedintables.ThreegapsinEPCbetweenChinaandforeigncountriesweresuggested.KeyWords:Survey,EPC,StatasQuoREAlloyBehaviorinCastAlAlloyMeltDuringDegassingHanKuiMaoXieminOuyangZhiyingMiaoChuanrongZhangGuangquan(ShanghaiUniversity,Shanghai,China)2004(2)6162AbstractTheproperREadditiontocastAlmeltcanobviouslyde2creaseamountsofgas/pinholeinsolidifiedalloy.ItisfoundedthatstableRE2hydridewasformedresultinginthedecreaseoffreeHcontent.TheREeffectsonimpurityremovaldecreaseheterogeneousnucleationsiteofbubbletofurtherenhancethegasremovalandpu2rificationeffect.KeyWords:CastAlAlloy,RE,RE2richPhase,RE2hydride,HydrogenDegassingEffectsofCeonMicrostructuresandPropertiesofZA27AlloyChenYan(ShanghaiLiancheng(Group)Co.,Shanghai,China)XieJingpeiChenQuande(HenanUniversityofScienceandTechnology,Luoyang,China)2004(2)6365AbstractTheproperadditionofCeintoZA27alloycanpromotetherefinementofthemicrostructureandamplitudedecompositioneffectivelysoastosignificantlyimprovethetoughness,dampingpropertyandwearresistanceoftheZA27alloy.AnewfrontierforapplicationoftheZA27alloywasdeveloped.KeyWords:Toughness,DampingProperty,WearResistanceSponsors:FoundryInstitutionofChineseMechanicalEngi2neeringSociety,WuhanResearchInstituteofMe2chanicalTechnologyEditorinChief:YuanZhenguoPublisher:JournalOfficeofSpecialCasting&NonferrousAlloysAddress:No.49MinzhuStreet,Hankou,Wuhan,HubeiProvince,ChinaTel:008622728582470485424406Fax:0086227285830827E2mail:[e-mail]://(P.O.Box399.BeijingChina)CodeNo:BM6644(ISSN100122249/