简介:SmOHCO3micro/nanoparticleswerepreparedinwater/oil(W/O)reversemicroemulsioncomposedofcetyltrimethylammoniumbromide(CTAB),n-octane,n-butanol,Sm(NO3)3·6H2Oandureaaqueoussolutionbythecouplingrouteofhomogeneousprecipitationwithmicroemulsion.ThenanoparticleswerecharacterizedandanalyzedbyX-raypowderdiffraction(XRD),thermalgravimetricanddifferentialthermalgravimetricanalysis(TG-DTG),Fouriertransforminfraredabsorptionspectra(FT-IR)andscanningelectronmicroscope(SEM).TheresultsshowedthatthephaseSmOHCO3micro/nanoparticleswasinagreementwithpureorthorhombicphase.ThedifferentmorphologiesofSmOHCO3micro/nanoparticleswithgoodmonodispersityandsizewereobtainedbyregulatingthereactiontemperatureandreactiontime.PossibleformationmechanismsofthemorphologicalstructureofSmOHCO3wereproposedanddiscussed.
简介:用Ce的蚀刻的技术是为擦亮并且塑造钻石电影的一个方便、快的方法。在这研究,擦亮象在表面crystallinity和钻石电影的阶段作文上擦亮温度和时间那样的参数的影响彻底地经由象FWHM和ID/IG那样的拉曼系列的分析被调查。而且,在与Ce擦亮以后的钻石的graphitization上的问题进一步包括FWHM通过拉曼数据的深度分发的详细学习被研究,ID/IG,和与热铁的金属完全不同的结果擦亮被获得。结果证明擦亮的钻石电影在擦亮前比那些有更加更高的钻石内容,并且不,一点graphitization在擦亮的被发现,由于在在转变金属的比那的稀土元素金属Ce的碳的更高的溶解度,并且与Ce擦亮的电影的原来的crystallinity没败坏。
简介:Inconel718superalloycoatingwaspreparedonamartensiticsteelsubstratebycoldgasdynamicspraying(CGDS).Microstructureandmicro-hardnessofthecoatingwerecharacterizedbymeansofscanningelectronicmicroscope(SEM),energydispersivespectrometer(EDS),andmicro-hardnessandnano-indentationtests.Theresultshaveindicatedthatthecoating’sthicknesscanreachmorethan300μm,andthereexistsagoodinterfacialcohesionbetweenthecoatingandthesubstrate.Thequantityandsizeofthedefectsatthebottom,middleandtopareasincreasegradually.ThereisnosignificantchangetotheoriginalmicrostructureoftheInconel718superalloyparticleaftertheprocessofCGDS;andanobvioustorsionaldeformationontheparticle’sprofileisproducedwhilelittledeformationatthecenterpartoccurs.Themicro-hardnessofthecoatingatthebottom,middleandtopareasdecreasesinturn.Comparedwiththebottomarea,themicro-hardnessofthemiddleandtopareasdecreasesbyabout10%and21%,respectively.Thenano-hardnessofthecoatingismuchlowerthantheoriginalparticle,whichdecreasesbyabout13.5%atthebottomareaand28%atthetoparea,respectively.Thedistributionofmicro-defectsisanimportantfactortothemicro-hardnessofthecoating.
简介:Superduplexstainlesssteels(SDSS)showcomplexprecipitationandtransformationbehaviorduringheattreatmentprocesses,whichaffectsbothmechanicalandcorrosionproperties.ThisreportpresentssomedataonthemicrostructuresthatdevelopafterfoldingandsubsequentprecipitationduringheattreatmentofUNSS32750SDSSsheetsamples.ThemicrostructuralandtexturalchangeshavebeenfollowedusingSEM/EBSDtechniques.Uponfolding,bothatextureandstraingradientforminthefolded/bentregion,subsequentheattreatmentat845℃resultsintheferritephasetotransformtosigma,austeniteandchiphases.Transformationwasfoundtobeacceleratedbystrain.Completetransformationoftheferritephaseoccurredwithinhalftheannealingtimerequiredintheunstrainedregions.Thelocalmis-orientationsintheferriteandaustenitephasesreducedduringannealing,however,thereductionintheaustenitewasnotveryhighandasignificantamountremainedevenafterthelongestannealingtime.Thetexturecomponentsthatdevelopedduringthefoldingprocessremainedunchangedevenafteronehourannealingat845℃.TheimplicationofthesefindingscouldhaveabearingontheformationofsigmaphaseduringweldingofSDSSthatmayhaveresidualstressesintroducedduringfinalprocessing.
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简介:Theeffectsofthefinalelectromagneticstirring(EMS)onthesolidificationstructureof60Si2CrVAThighstrengthspring(HSS)steelofcontinuouscasting(CC)billetshasbeenstudied.Theanalysisofthesolidificationstructureisbasedonthecomparisonbetweenthemacrostructure,microstructure,carbonsegregationanddefectsofthe60Si2CrVATbilletwithmold-electromagneticstirring(M-EMS)andthosewiththeM+finalsolidificationzoneelectromagneticstirring(F-EMS).ItisfoundthatthesolidificationstructureofthebilletwiththeF-EMSisimprovedwiththetightnessofthebilletandtheincreaseintheratiooftheequiaxedstructure,theinnerporosityandtheshrinkageareremarkablyreduced,andthattheratioofcentralcarbonsegregationsharplydecreases.Meanwhile,thesecondarydendritearmspacing(SDAS)isimproved,andtheratioofcentralequiaxedgrainconsiderablyincreases,whichresultsinfinergrains.Therefore,thequalityofthebilletisenhancedwiththeF-EMS.