简介:为尺寸依赖者的一个模型极其细小的粒子的起始的sintering温度被建立。为W,Ni和Ag的尺寸依赖者sintering温度的理论预言极其细小的粒子与可得到的试验性的证据一致。(编辑作者摘要)18个裁判员。
简介:有在2~6的范围的厚度的极端薄铝电影0nm被dc磁控管劈啪作响扔了仪器。获得的样品的反射和发射度与一个WFZ-900-D4UV/VIS分光光度计被测量。光常数(n,k)并且介电常数(ε',ε')被使用Newton-Simpson周期性的替换决定方法。结果显示极端薄铝电影的电磁的组成的特征是厚度的功能并且有明显的尺寸效果。
简介:SkeletalformofKNbO3crystalsgrowinginLi2B4O7solventwasin-situobservedat900CanditwasfoundthatshallowdepressionstartedtodeveloponthesurfaceofKNbO3crystalswhenthecrystalsizeexceededseveralmicron,typically7micron.BasedonthequantitativecriterionderivedbyChernov,theestimatedcriticalsizeofKNbO3crystalswas1micron,whichwasconsistentwiththeexperimentalmeasurement.Thekineticcoefficients,kcerandkc,,inthecriterionwereexperimentallyobtainedinthediffusive-convectiveanddiffusive-advectiveflowstatesrespectively.
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简介:Anewmethodusingleadcoatedglassfibertoproducecontinuouswireforbatterygridofelectricvehicles(EVs)andhybridelectricvehicles(HEVs)wasintroduced.Underequalflow,boththemaximumandminimumtheoreticalvalueofgapsizewerestudiedandestimationequationwasestablished.Theexperimentalresultsshowthatthegapsizeisakeyparameterforthecontinuouscoatingextrusionprocess.Itsmaximumvalue(Hmax)is0.24mmandtheminimumone(Hmin)is0.12mm.Atagapsizeof0.18mm,themaximumofmetalextrusionperunitoftimeandoptimalcoatingspeedcouldbeobtained.
简介:Thelargesize,crack-freeZr55Cu30Al10Ni5bulkmetallicglass(BMGs)withthediameterof54mmandtheheightof15mmwasbuiltbylasersolidformingadditivemanufacturingtechnology,whosesizeislargerthanthecriticaldiameterbycasting.Themicrostructure,tensileandcompressivedeformationbehaviorsandfracturemorphologyoflasersolidformedZr55Cu30Al10Ni5BMGswereinvestigated.Itisfoundthatthecrystallizationmainlyoccursintheheat-affectedzonesofdepositionlayers,whichconsistofAl5Ni3Zr2,NiZr2,ZrCu,CuZr2phases.Thecontentofamorphousphaseinthedepositisabout63%.Underthecompressiveloading,thedepositpresentsnoplasticitybeforefractureoccurs.Thefractureprocessismainlycontrolledbytheshearstressandthecompressiveshearfractureanglesofabout39.Thecompressivestrengthreaches1452MPa,whichisequivalenttothatofas-CastZr55Cu30Al10Ni5BMGs,andthereexistvein-likepatterns,river-likepatternsandsmoothregionsatthecompressivefractography.Underthetensileloading,thedepositpresentsthebrittlefracturepatternwithoutplasticdeformation.Thefractureprocessexhibitsnormalfracturemodel,andthetensileshearfractureangleofabout90°.Thetensilestrengthisonlyabout609MPa,andthetensilefractographymainlyconsistsofmicro-scaledcoresandvein-likepatterns,dimple-likepatterns,chocolate-likepatternsandsmoothregions.Theresultsfurtherverifiedthefeasibilityandlargepotentialoflaseradditivemanufacturingonfabricationandindustrialapplicationoflarge-scaleBMGsparts.
简介:Soldersizeeffectonearlystageinterfacialintermetalliccompound(IMC)evolutioninwettingreactionbetweenSne3.0Age0.5Cusolderballsandelectrolessnickelelectrolesspalladiumimmersiongold(ENEPIG)padsat250Cwasinvestigated.TheinterfacialIMCstransformedfrominitialneedle-androdtype(Cu,Ni)6Sn5tododecahedron-type(Cu,Ni)6Sn5andthentoneedle-type(Ni,Cu)3Sn4attheearlyinterfacialreactionstage.Moreover,theseIMCtransformationsoccurredearlierinthesmallersolderjoints,wherethedecreasingrateofCuconcentrationwasfasterduetotheCuconsumptionbytheformationofinterfacial(Cu,Ni)6Sn5.Onthermodynamics,thedecreaseofCuconcentrationinliquidsolderchangedthephaseequilibriumattheinterfaceandthusresultedintheevolutionofinterfacialIMCs;onkinetics,largersolderjointshadsufficientCufluxtowardtheinterfacetofeedthe(Cu,Ni)6Sn5growthincontrasttosmallersolderjoints,thusresultedinthedelayedIMCtransformationandtheformationoflargerdodecahedron-type(Cu,Ni)6Sn5grains.Insmallersolders,nospallingbuttheconsumptionof(Cu,Ni)6Sn5grainsbytheformationof(Ni,Cu)3Sn4grainsoccurredwheresmallerdiscrete(Cu,Ni)6Sn5grainsformedattheinterface.