简介：Inthispaper,onthebasisofthephase-shiftedcontrolledzero-voltage-switch(ZVS)full-bridgeconverterwithpulsewidthmodulation(PWM),anovelzero-voltageandzero-currentswitch(ZVZCS)PWMconverterusingasimpleauxiliarycircuitwasdesigned.TheZVZCSsoftswitchisachievedbytheresonanceamongtheresistingelectromagneticdeflectioncapacitor,thecapacitorofthesimpleauxiliarynetworkandtheleakageinductoroftransformer.Therearenodissipationdevicesofthesaturationinductorandtheauxiliaryswitchintheconverter,meantimethecapacitoroftheauxiliarycircuitisalsousedtoclampthevoltageoftherectifier,andthereisnoadditionalclampedcircuit.Thereisnobigcirculatingcurrentintheconverter,alltheactiveandpassivedevicesworkontheconditionofthelowcurrentandvoltagestress,andtheproposedconverterhaswideloadrangeandsmalldutyloss.

简介：ＰｈａｓｅＥｑｕｉｌｉｂｒｉａＣａｌｃｕｌａｔｉｏｎｏｆｔｈｅＧａＩｎＳｂＴｅｒｎａｒｙＳｙｓｔｅｍＸｉｅＹｕｎ′ａｎ，ＱｉａｏＺｈｉｙｕ，ＸｉｎｇＸｉａｎｒａｎａｎｄＷａｎｇＣｏｎｇ（谢允安）（乔芝郁）（邢献然）（王聪）Ｄｅｐｔ．ｏｆＰｈｙｓ...

简介：ＣｏｅｒｃｉｖｅＦｏｒｃｅｏｆγ－ＰｈａｓｅｉｎＷＣ－ＣｏＣｅｍｅｎｔｅｄＣａｒｂｉｄｅｓＬｉｕＳｈｏｕｒｏｎｇａｎｄＳｕｎＪｉｎｇ（刘寿荣）（孙景）（ＴｉａｎｊｉｎＩｎｓｔｉｔｕｔｅｏｆＨａｒｄＡｌｌｏｙｓ，Ｔｉａｎｊｉｎ３００２２２，Ｔｉａｎｊｉ...

简介：Inthispaper,anumericalinvestigationaboutthemetaltransferofGMAWisinvestigatedbasedonthephasefieldmodel.Bedifferentofmostpublishedwork,wetakethethermocapillaryeffectandmixtureenergyintotheprocessofphasetransferandinterfacechangewhichisdifferentfromvolumeoffluid(VOF)method.Wediscretizethewholemodelwithacontinuousfiniteelementmethodandwealsoapplyapenaltyformulationtothecontinuityconditionenhancingthestabilityofthepressure.MetaltransferofGMAWwithconstantandpulsecurrentiscomputedasnumericalexampleswhichagreeswellwiththedataofhigh-speedphotography.Theresultshowsthatthecomputingprocessofthephasefieldmodelisstabilityandithasahigherprecisioninpredictingthediameterofdroplet.

简介：ThesubmicronpowdermixturesofTiC-TiN-WC-Mo-C-Nisinteredat1400℃orbelowinvacuumwerestudiedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM)analyses.TheresultsshowedthatMo2Cformedat800℃orbelow.BothWCandMo2Cdisappearedat1200℃,andTiNdisappearedat1250℃.Inaddition,thevariationsoflatticeconstantsofthetitaniumcarbonitrideandnickelbinderphasewithsinteringtemperaturewereexperimentallyobtained,andthereasonwasanalyzed.

简介：Theliquid-filmsolution-diffusionbondingofZCuBe2.5alloyswasconductedusingCu-basedalloypowders.Thetensilestrengthofthebondingtimedecreasesandtheinterfacemigrationvelocityincreasesbondingtime,thethicknessofdiffusionlayerincreaseswiththeincreaseoftemperaturegradient,andthistendencybecomesmoreremarkablewiththeprolongingofbondingtime.

简介：

简介：DD6alloywasbondedbytransientliquidphase(TLP)diffusionbonding.Themaincompositionsoftheinterlayeralloyemployedweresimilartothoseofthebasemetal,DD6,andacertainamountofelementBwasaddedasthemeltingpointdepressant.Theresultsshowthatitisdifficulttoobtainthejointswiththemicrostructurescompletelyhomogeneous.ForthejointTLPdiffusionbondedat1290℃for12h,abouthalfareasofthebeampossessedαγ+γ′microstructure,nearlyidenticalwiththatofthebasemetal,andtheotherlocalareasconsistedofT-solution,borides,etc.Prolongingthebondingtimeto24h,theinhomogeneousareasinthejointreduced,andthejointpropertyimproved.Thejointstress-rupturestrengthat980℃and1100℃reached90%-100%and70%-80%ofthoseofthebasemetalrespectively.

简介：

简介：晶体结构和加氢行为(La_(1-x)Mg_x)_3Al(x=0.1，0.2，0.3，和0.4)合金被调查。这被发现有x=的合金0.1La和第0.2consi(Mg，艾尔)，La，和一个新奇阶段。新奇阶段作为La_2Al被决定。当Mg满足增加，La_2Al的数量减少，这被显示出。当x增加到0.3时，onlyLa(Mg，艾尔)并且La_2Al的小数量存在。当x是0.4时，La_2Al阶段消失，合金包含两La(Mg，艾尔)并且La(艾尔，Mg)_2洗阶段。(La_(0.9)Mg_(0.1))_3Al并且(La_(0.7)Mg_(0.3))_3Al合金能被氢的吸收在473K分解成LaH_3，MgH_2，和La_2Al_5。

简介：用于有机化合物的抽取的稳固阶段的抽取(SPE)技术有创作力地在纸被用作无机的黄金的抽取。技术的二种类型被建议并且探索，也就是SPE和第四级的铵表面活化剂的liquidliquid抽取(LLE)[cetytrimethyl铵溴化物(CTMAB)，cetylpyridine溴化物(CPB)，本甲基dimethyldodecyl铵氯化物(BDMDAC)，并且dodecyltrimethyl铵氯化物(DTMAC)]。表面活化剂能与Au(CN)2到形式，离子的建筑群，和混合物能被反向阶段的结合的硅石胶化的SPE列提取。因此，SPE的一个新方法被建议与高选择，可靠性，和简洁的这些特征提取黄金。黄金的恢复率是超过98的试验性的结果表演?%，和稳固阶段的抽取列容易没被损坏，它能反复被使用。新方法能也从碱的氰化物答案被用作黄金的抽取过程。而且，纸也提出金抽取的一个新过程。

简介：Dynamicsinpartialtransientliquidphasebonding(PTLPbonding)ofSi3N4ceramicwithTi/Cu/Timulti-interlayerwassystematicallystudiedthroughmicro-analysisofjointinterfaces.Theresultsshowthatgrowthofreactionlayerandisothermalsolidificationprocessiondoatthesametime.GrowthofreactionlayerandmovingofisothermalsolidificationinterfaceobeytheparaboliclawgovernedbythediffusionofparticipatingelementsduringthePTLPbonding.Coordinationoftheabovetwodynamicsprocessisdonethroughtimeandtemperature.Whenreactionlayerthicknessissuitableandisothermalsolidificationprocessisfinished,thehighbondingstrengthatroomtemperatureandhightemperatureareobtained.

简介：Inthisstudy,atwo-stepheatingprocessisintroducedfortransientliquidphase(TLP)diffusionbondingforsoundjointswithT91heatresistantsteels.Atfirst,ashort-timehighertemperatureheatingstepisaddressedtomelttheinterlayer,followedbythesecondsteptocompleteisothermalsolidificationatalowtemperature.Themostcriticalfeatureofournewmethodisproducinganon-planarinterfaceattheT91heatresistantsteelsjoint.WeproposeatransitionalliquidphasebondingofT91heatresistantsteelsbythisapproach.Sincejointmicrostructureshavebeenstudied,wetestedthetensilestrengthtoassessjointmechanicalproperty.Theresultindicatesthatthesolidifiedbondmaycontainaprimarysolid-solution,similarcompositiontotheparentmetalandfreefromprecipitates.Jointtensilestrengthofthejointisnotlowerthanparentmaterials.Jointbend'sstrengthsareenhancedduetothehighermetal-to-metaljunctionproducinganon-planarbondlines.Nevertheless,thetraditionaltransientliquidphasediffusionbondingproducesplanarones.Bondingparametersofnewprocessare1260℃for0.5minand1230℃for4min.

简介：Anewtechnology,thetwo-steptransientliquidphasediffusionbonding(TLP-DB)technologyforcobalt-basedK640superalloy,wasinvestigated.Themethodconsistsofashort-timehightemperatureheatingtomeltinterlayerfollowedbyisothermalsolidificationofliquidphaseatalowertemperaturethanthatoftheconventionalTLP-DB.Theresultindicatesthatthetwo-stepTLP-DBcanreliablyproduceanidealjointwithuniformchemicalcomposition,whichissuperiortothejointweldedbyconventionalTLP-DBinmicrostructureandmechanicalproperties.Bondingparametersofnewprocessare1250℃for0.5hand1180℃for3h.Thehigh-temperaturetensilestrengthofthejointbytwo-stepTLP-DBreaches74%ofthatofthebasematerialonanequalbasis,butthehigh-temperaturetensilestrengthofthejointbyconventionalTLP-DBisonly58%ofthatofthebasematerial.

简介：ThesecondphaseparticledispersedinmicroaUoyedsteelhasdifferenteffectsongraingrowthdependingontheirsizeandvolumefractionofthesecondphaseparticleswhichwillchangeduringweldingthermalcycles.Theparticlecoarseninganddissolutionkineticsmodelwasanalyzedforcontinuousheatingandcooling.Inaddition,basedonexperimentaldata,thecoupledequationofgraingrowthwasestablishedbyintrodacinglimitedsizeofgraingrowthwiththeconsiderationofthesecondphaseparticlespinningeffects.UsingMonteCarlomethodbasedonexperimentaldatamodel,thegraingrowthsimulationforheat-affectedzoneofmicroalloyedsteelweldswasachieved.Thecalculatingresultswerewellinagreementwiththatofexperiments.

简介：基于锆的合金的Intermetallics和阶段转变，Zr-1.0Sn-0.3Nb-0.3Fe-0.1Cr，被常规X光检查调查衍射(XRD)，微分扫描热量测定(DSC)，和膨胀测量。三种类型也就是，猛抛(ZrNb)2Fe，Zr(CrFe)2，并且Zr3Fe，被XRD检测。立方的Ti2Ni类型(ZrNb)2Fe被发现是主要猛抛在里面合金，和它被建议溶解在861点

简介：1.6公里厚的表的非合金的钛的变硬的激光转变(LTH)，更近，到ASTM，等级3化学作文用2kWCWNd被调查:钇铝柘榴石激光。激光力量的效果(750-1250W)，扫描速度(10003000mm/min)和焦点的点位置(从?10到?30公里)在热输入，和变硬祷告的几何学上(即变硬的祷告宽度(HBW)，变硬的深度(HD)和变硬的祷告的入口的角度与表面(AEHB)介绍)用反应表面方法论(RSM)被调查。试验性的计划基于Box-Behnken设计矩阵方法。为预言热输入和变硬的祷告几何学的线性、二次的多项式方程被开发。结果显示建议模型在变硬的参数的限制以内足够地预言回答被使用。回归方程能被用来为需要的标准发现最佳变硬条件，这被建议。

简介：Microstructureoftransientliquidphase(TLP)diffusionbondedathirdgenerationsinglecrystalsuperalloyjointwasinvestigatedusingscanningelectronmicroscopy(SEM),andmechanicalpropertiestestofjointwascarriedout,forobtainingrelationshipbetweenmicrostructureandmechanicalpropertiesofjoint.Theresultsshowedthatthejointcontainedbondingzoneandbasemetal.Thediffusionzonewasobviouslyobserved.Whenitwasnotfinishedforisothermalsolidificationprocess，thebondingzonewouldcontainisothermalsolidificationzoneandrapidsolidificationzone.Metallographicexaminationrevealedthatisothermalsolidificationzonewasconsistedofyandphase.Rapidsolidificationzonewasconsistedoftwodifferentstructures,whichwereternaryeutecticofborides,yandy,phasedevelopingattheedgeofjoint,binaryeutecticofyandphaseappearingintheportionofjoint.Whenitwasnotenoughforhomogenizationprocessundertheconditionoffinishingisothermalsolidificationprocess,thebondingzonewouldcontainisothermalsolidificationzoneandboridesattheinterface.Undertheconditionsofrelativelyhighweldingtemperatureandlongweldingtime,averagetensilestrengthofjointwasequivalenttothatofparentmaterial.

简介：TheanalysisofthemicrostructuralcharacterizationandphasecompositionofelectronbeamweldedjointzonesofTi-43Al-9V-0.3Yalloyhasbeendoneinthisstudy.TheweldedseamismainlycomposedofB2phase,thepartialγ+α2two-phaselamellarstructureandgranularγmphase.AndthelanthanonYexistedasYAl2phaseandservedasgrainrefined.Theimpactofdifferentcoolingratesonjointmicrostructure,fracturecharacteristicandtensilestrengthwereinvestigated.Thehighcoolingraterestrainedthestructuraltransformationandresultedintheorderingstructure.Thefractureofthejointwasbrittlecleavagefracturebecausetheorderingstructurewentagainstrestrainingthecrackpropagation.Withthedecreaseofcoolingrate,thetransformationamountsoflamellarstructureincreased,andthefracturepresentedthelayeredandcross-layeredcharacteristic.

简介：电子结构和在不同压力(260，320，400和600GPa)的新奇Na-hP4高压力阶段的光性质被密度调查有为交换和关联精力的概括坡度近似(GGA)的功能的理论(DFT)。沿着在Brillouin地区，状态(DOS)的密度和状态(PDOS)的部分密度的更高的对称斧子的乐队结构被介绍。乐队差距增加，精力乐队膨胀到某程度，压力增加。绝缘的功能，反射率，精力损失功能，光吸收系数，光传导性，折射索引和扑灭系数为在不同压力讨论Na-hP4高压力阶段的光性质被计算。