简介:Yttriastabilizedzirconia(YSZ)haswidelybeenusedaselectrolyteinsolidoxidefuelcell(SOFC).ThemicrostructureofYSZrelatedtothefabricationprocesswasdiscussedinthepaper.WithYSZnano-powdersabout40-100nmasrawmaterial,theYSZadobewasmanufacturedbytapecalenderingprocess.Thenamedthree-stepsinteringprocesswasperformedat1000℃for2h,thenraisedthetemperaturewithnormalrateandassoonasupto1400℃,thefurnacewascontrolledat1250-1300℃for10-20h.ThehighdenseYSZswiththerelativedensityof96%-99%wereobtained;thegrainsizeofYSZcouldbereducedto0.5-3μm.Theaboveresultisbenefitedtoco-firedintheelectrode-supportedSOFCs.
简介:Theelevatedtemperaturetensileexperimentshavebeencarriedoutonthemagnesiumalloyandresultsindicatethatthemagnesiumalloyhasexcellentsuperplasticproperty.Gleebe-1500testingmachinewasusedinthediffusionbondingexperimentonthesuperplasticmagnesiumalloy.Then,theshearstrengthofthejointsunderdifferentconditionsisobtainedthroughsheartestingandtheoptimumprocessingparametersforthediffusionbondingareachieved.Bymetallurgicalmicroscopeandscanningelectronmicroscope(SEM),itisrevealedthatthemicromechanismofdiffusionbondingistheslideofgrainboundariescausedbythegrowthofgrainsandatomdiffusionofthesuperplasticmagnesiumalloy.
简介:Tostudytheinfluencelawsofweldingparametersonweldporosity,underwaterwetflux-coredarcwelding(FCAW)duplexstainlesssteelS32101wascarriedoutinahyperbaricchamber,andthesecond-ordermultipleregressionequationwasestablished.Theinteractiveeffectsofweldingparametersontheporositywereanalyzedbythethreedimensionalresponsesurfacesandthecontourplots.Theresultspresentthattheinteractioneffectbetweenwaterdepthandvoltageontheporosityisthemostsignificant.Theoretically,anon-poresweldbeadcanbegainedbyreasonablymatchingtheseparameterswithwaterdepthlessthan10m.Always,theweldporosityreachesitspeakvaluewitha7mm/sweldingspeed.
简介:Thetenacityofheat-affectedzone(HAZ)willdeclineandthesizeofgrainswillincrease,becauseoftheoverheatingonHAZwhensubmergedarcwelding(SAW)isusedtothickplatewithhighheatinput.TheshapingwillworsenwhenSAWisusedtothinplatewithhighcurrentathighspeed.AnewSAWtechnology,thepulseddirectcurrent(DC)automaticSAW,willbeputforwardinthispaperinordertoovercometheaboveshortcomings.Andapulsedcontrollerwithmicro-controllerunit(MCU)asthecore,nixietube(NT)andkeyboardastheman-machineconversationinterfaceisdeveloped.Themainfunctionsofthepulsedcontrollerincludetheoutputofpulsedweldingcurrentandtheworkingwithtwinwire.Theresearchhaswidelyprospectsinapplicationwithsignificantmeaningsintheoryandpracticalengineering.
简介:ColdMetalTransfer(CMT)weldingtechniqueisanewweldingtechniqueintroducedbyFroniuscompany.CMTweldingofnickel-basedalloywithstainlesssteelwascarriedoutusingCuSi3fillerwireinthispaper.Effectsofweldingparameters,includingweldingcurrent,weldingspeed,etc,onweldsurfaceappearanceweretested.MicrostructureandmechanicalpropertiesofCMTweldwerestudied.Theresultsshowthatthethicknessofinterfacereactionlayerofthenickel-basedalloyis14.3μm,whichisonly4.33%ofbasematerial.Theweldismadeupoftwophases,α-copperandiron-basedsolidsolution.Ruptureoccursinitiallyattheweldedseamneartheedgeofstainlesssteelinsheartest.ThemaximumshearstrengthoftheCuSi3weldedjointis184.9MPa.
简介:Electronbeamweldingplaysanimportantroleintheaerospaceindustrywherecomponentslikesensors,gears,actuatorsandairframesusedinaircraftandrocketengineswereweldedusingthistechnique.Weldingisnormallyperformedinavacuumtoavoidthescatterofelectronduetothepresenceofgasmoleculesintheatmosphereandhenceelectronbeamweldingprocessprovidesthegreaterresults.Butstilljoiningofdissimilarmetalsischallenging.Thispaperrepresentsreviewofprocess,generationanddistributionofheatsourcevariousinputparameters,materials,microstructure,mechanicalstrengthandthepossibilitiesofjoiningdissimilarmetalsusingelectronbeamwelding.
简介:Sinceamorphousalloyshavewiderapplication,theycannotbefabricatedusingtheconventionalcoolingvelocity.ThebarmaterialplasmasprayingisadoptedtofabricateFebaseamorphousalloyinthisinvestigation.Thecrystallizationdegree,microstructure,micro-hardness,composition,crystallizationtemperatureoftheamorphousalloyandtheflyingrulesoftheatomizedparticlesintheprocessoftheplasmasprayaretested.Theresultsshowthatthealloypreparedhasthehighamorphousdegreeandhomogeneousmicrostructure,micro-hardnessandthecrystallizationtemperaturecanreach1187HVand531℃respectively.Theatomizationisverywellduringtheprocessofplasmaspraying;andthereishighthermalgradient,thecoolingvelocityreaches6.07×107K/s.
简介:Obtainingtheimageofmoltenpoolaluminumalloy'stungsteninertgas(TIG)weldingbecomesachallengingproblemintheweldingfield.Inthispaper,abran-newopticalsensorbasedanalyzingthelightspectrumwasdesigned,andtheclearimageofthemoltenpoolduringthealuminumalloy'sweldingusingthecommonindustrialCCDcamerawasobtained.Andwiththenewalgorithmprovidedbymyself,thedesirablecharacteristicparametersofthemoltenpoolofaluminumalloy'sweldingwereobtained,anditprovidesagoodbaseforadvancedmonitorweldingquality.
简介:WiththebackgroundofthecontrolofadditionalmechanicalforcedroplettransferinMIG/MAGwelding,regardingtheACservomotorascore,anoveloscillatingwirefeedingsystemhasbeendevelopedwithexcellentperformancesofcontrolanddynamicaccelerationwhichistested.Systemconstitutionandoperationprincipleareintroducedinthispaper.Influencesofparametersondynamicaccelerationperformanceareanalyzedanddiscussedemphatically,suchasoscillatingfrequency,oscillatingamplitudeanddraw-backspeed.Experimentalresultindicatesthataccordingtothetechniqueofweldingcontrol,thenovelwirefeedingsystemrespondsrapidlytovariouskindsofcontrolordersofwirefeedinganddraw-back,andrealizesflexiblecontrolofweldingwireaxialmovement,includingdynamicshifting,oscillatingandsoon.
简介:在过去的十年,biohydrometallurgy的领域里的进步是重要的。17新奇biomining微生物的一个总数被发现,并且八铜堆bioleaching种并且11黄金biooxidation植物被建立或膨胀。在这评论,它被总结为学习微生物引起的社区动力学和结构的最新孤立的biomining微生物和三个新奇微生物引起的生态的方法的生理的性质。另外,关于象铀,铝,碲,金者,铟,和第二等的稀罕金属资源那样的稀罕金属的biohydrometallurgy研究,以及象铜,镍,钴,和黄金那样的重非铁的金属被考察了,与在中国的一个重音。在未来,黄铜矿,稀罕金属,从废物的第二等的资源,和资源利用引起的环境污染的bioleaching上的进一步的研究是必要的。图形的AbstractZijinshan堆bioleaching植物与30,000的能力在2012重启操作?tonent蠨?蠨吗??
简介:Quantitativeresearchontheheataffectedzone(HAZ)ofweavebeadwelding(WBW)jointforInvaralloyiscarriedoutinthispaper.Basedonthemorphologyandrelateddataanalysisoftheweldseam,thewidthdifferenceofeachlayerandtheformingmechanismareanalyzed.Resultsshowthatthebottomlayer(Layer1)hasthewidestHAZandthesmallestfluctuation,whichreaches1200μm.HAZwidthoflayer2to5isrelativelynarrowerwhichisbasicallybelow600μm,whiletheamplitudefluctuationisgreater.Themainreasonliesintheweldingpath.Thelongstraightweldingwithoutweavecausesthebasemetalnearthegroovefullymeltswhichcausesbythelongstraightweldingwithoutweave,whileweldingwithweaveleadstotheunevenandinadequatemeltingofmetalneargroove.