資源描述：
《_英文_行波磁場對定向凝固pb_sn合金枝晶生長的影響》由會員上傳分享，免費在線閱讀，更多相關內容在教育資源-天天文庫。
1、------------------------------------------------------------------------------------------------_英文_行波磁場對定向凝固Pb_Sn合金枝晶生長的影響_MINZhi-xian,SHENJun,WANGLing-shui,LIULinStateKeyLaboratoryofSolidificationProcessing,NorthwesternPolytechnicalUniversity,Xi’an710072,ChinaReceived28Septemb
2、er2010;accepted24June2011EffectoftravelingmagneticfieldondendritegrowthofPb-SnalloyduringdirectionalsolidificationAbstract:Theinfluenceofmeltconvectionondendritegrowthduringtheupward-directionalsolidificationofPb-33%Snbinaryalloyswasinvestigated.Themeltconvectionwasmodulatedbytr
3、avelingmagneticfield.Whenthedirectionoftravelingmagneticfieldwaschangedfromupwardtodownward,theprimarydendritespacinggraduallyincreased,andthedistributionpeakoftheprimarydendritespacingshiftedtothefieldofnarrowerspacing.Theseresultfromthedifferentintensitiesofmeltconvection,whic
4、harecontrolledbythetravelingmagneticfield.Theeffectsofthetravelingmagneticfieldonmeltconvectionaresimilartothoseofadjustmentinthegravitylevel,thus,theprimarydendritespacingvaries.Whentheintensityofthetravelingmagneticfieldwas1mT,andthedrawingspeedwas50μm/s,thegravityacceleration
5、reached0.22gforthedownward-travelingmagneticfieldand3.07gfortheupward-travelingmagneticfield.Keywords:directionalsolidification;microstructure;Pb-Snalloy;——————————————————————————————————————---------------------------------------------------------------------------------------
6、---------travelingmagneticfield1IntroductionDendritesarethemostcommonpatternsduringdirectionalsolidification.Dendriteformationincludesmanycharacteristicpropertiesandlengths,suchasprimarydendritespacing,secondarydendritespacing,anddendritetipradius.Inordertodescribetheselengths,d
7、etailedtheoreticalmodelswereestablishedunderdiffusiveconditions[1].Inmostexperimentalstudies,however,theconvectioneffectsplayanimportantroleinterrestrialconditions,thuscausingconflictsbetweenthetheoreticalpredictionsandexperimentalresults.Recentstudiesshowedthatconvectionhassign
8、ificanteffectsondendritespacing[2?3].Manymethod
