简介:Inthisstudy,tungsten(W)wascoatedonacopper(Cu)substratebyusingdouble-glowdischargetechniqueusingapureWpanelasthetargetandargon(Ar)asthedischargeandsputteringgas.ThecrystalstructureoftheWcoatingwasexaminedbyX-raydiffraction(XRD).Scanningelectronmicroscopy(SEM)wasperformedwithcross-sectionimagestoinvestigatethepenetrationdepthofWintotheCubody.Additionally,thepropertiesofwearabilityresistance,corrosionresistanceandmechanicalstrengthoftheWcoatedCumatrixwerealsomeasured.Itisconcludedthatindouble-glowplasma,WcoatedCucanbefacilelyprepared.ItisnoticedthatthetreatmenttemperatureheavilydominatesthepropertiesoftheW-Cucomposite.
简介:RapidsolidificationofCu-Pbmonotecticalloyshasbeenaccomplishedduringfreefallina3mdroptube.BothmacrosegregatedanduniformlydispersedstructuresareobservedinCu-40wtpctPballoydroplets,whereasdropletsofcompositionCu-64wtpctPbexhibitonlymacrosegregationmorphologies.Themicrostructuresarestronglydependentondropletsize.Thehigherundercoolingtendstofacilitateliquidphaseseparationandresultsinmoreextensivemacrosegregationinsmallerdroplets.ThereexistsapronouncedtendencyforthePb-richliquidtooccupythesurfaceofthedropletsofbothcompositions,resultingfromthequitelowersurfacetensionofthePb-richphaseandcausingaPb-richlayeratthesurfaceofthesolidifieddroplet.ThenucleationofmonotecticcellsintheCu-40wtpctPbdropletswithdispersedstructurespreferentiallyoccursatthedropletsurface.Asinglenucleationeventtakesplacemorefrequentlyasdropletsizeisreduced.
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简介:CuprecipitationbehaviorsintwoCu-bearingausteniticantibacterialstainlesssteels,type304andtype317L,weresystematicallystudiedbyusingrelativelysimplemethodsformaterialsanalysis,includingmicro-hardness,electricalresistivity,electrochemicalimpedancespectroscopy,X-raydiffractionanddifferentialscanningcalorimetry.Theresultsindicatedthatafteragingatelevatedtemperature,themicro-hardness,electricalresistivity,electrochemicalimpedanceandlatticeconstantofthesteelwereallvariedatdifferentdegreesduetotheprecipitationandgrowthofCu-richphases.TheresultsalsoshowedthattheheatevolutionduringtheprocessofCuprecipitationcouldbesensitivelydetectedbymeansofdifferentialscanningcalorimetry,obtainningthestartingtemperature,peaktemperature,peakareaoftheCu-richprecipitation,andeventheactivationenergybycalculation.TheresultsconfirmedthattheCu-richphasedprecipitationintheCu-bearingausteniticantibacterialstainlesssteelshouldbeathermalactivationprocesscontrolledbyCudiffusion.AllthematerialsanalysismethodsusedinthisstudycanbemoresimpleandeffectiveforapplicationinR&DoftheCu-bearingantibacterialstainlesssteels.
简介:Thereisanincreasingtrendforproducingcopper-containingsteels,withcopperbeingeitheraresidualelementfromscrapsoranintentionaladdition,i.e.,inweatheringsteel.Theissueofsurfacehotshortnessoccursduringthehotworkingofsteelscontainingcopper,andasignificantamountofworkhasbeenperformedonthistopic.Thispaperprovidesareviewofrelatedstudiesonthisphenomenon.Theformationmechanism,asanalyzed,istheliquidmetalembrittlementcausedbytheliquidcopperpenetrationintoaustenitegrainboundariesatthemetalsurface,wherethecopperoriginatesfromtheselectiveoxidationofthesteelathightemperature.Onthebasisofthemechanism,moreimportanceisplacedonanalyzingtheeffectonthephenomenonbyvaryingthecontrollingfactors,includingtheheatingprocess,alloyingadditions,anddeformationconditions.Possiblesolutionstotheproblemarefinalized,andsomefurtherworkmustbeperformedinthefuture.
简介:摘要某500kV变电站GIS出现了接地刀闸三相联动连杆脱落问题,电动机构分合操作半分半合的问题。一次接地刀闸非全相动作导致其中两相接地状态合闸,导致相关GIS设备耐压试验不合格,设备停运。通过拆开故障设备,研究故障现象,找出故障原因,并就GIS类似结构的隔离刀闸和接地刀闸操作机构故障隐患提出改造意见,确保GIS设备安全稳定运行。
简介:摘要精锻技术是先进制造技术的重要组成部分,也是汽车工业、工程机械行业中应用广泛的制造工艺方法。可以加工净形连杆零件,如热精锻、冷锻和温锻都是应用了发展很快的精密塑性成形技术。连杆中锤锻模的结构设计对锻造结果有着很大的影响,因此本文对其进行了研究。
简介:摘要目前,很多柴油机生产企业都在运用计算机建模和仿真软件进行虚拟样机设计,通过产品的应力分析和热负荷分析可以尽早发现问题、解决问题,降低生产成本和制造风险。虚拟样机的仿真分析受众多企业的追捧,成为新世纪产品研发的主流技术之一。