熱處理及微量si元素對cu7.5ni5.0sn合金組織與性能的影響

1、分類號：密級：學(xué)號：6120100113612010011361201001136120100113單位代碼：10407104071040710407碩士學(xué)位論文研究方向銅合金加工技術(shù)開發(fā)與研究銅合金加工技術(shù)開發(fā)與研究專業(yè)名稱材料學(xué)研究生姓名楊勝利導(dǎo)師姓名、職稱柳瑞清柳瑞清教授教授李安運李安運教授教授2013年5月29日江西贛州論文題目:熱處理及微量熱處理及微量SiSiSiSi元素對元素對Cu7.5Ni5.0SnCu7.5Ni5.0Sn

2、Cu7.5Ni5.0SnCu7.5Ni5.0Sn合金合金組織與性能的影響組織與性能的影響IIAbstractAbstractAbstractAbstractBymeansofanalysismethodofmetallographicanalysisXRaydiffractionscanningelectronmicroscopeenergyspectrum.TheinfluenceofSiadditiononthemicrostruc

3、turepropertiesinCu7.5Ni5.0Snalloywasstudied.MeanwhileeffectoftheHeattreatmentprocessMachiningprocessontheCu7.5Ni5.0Snalloymicrostructurepropertieswasstudied.Theresultswereasfollowed:(1)Thereexistedseriousdendriticsegrega

4、tionintheascaststructureofCu7.5Ni5.0Snalloy.Theascastmicrostructureiscomposedofthreeparts:graydendrite(αphaseCuNisolidsolution)interdendriticclipwhitematterbonytissue(γ(CuXNi1X)3Sn)darkgraytissuetransitional(αphaseγphase

5、).TheascastmicrostructureisstillcomposedofthreepartsafterthetraceelementSiwasadded.WiththeincreaseofSicontentthedendriterefinementeffectisobvious.ButthecontentofSiismethan0.58%refinementeffecttendstobestable.Theadditiono

6、fSielementinthealloymainlyfmedNi2SiNi3SiNi31Si12phase.ThemainfmationoftheadditionSiareNi2SiphaseNi3SiphasewhenthecontentofSiislow.OtherwiseitwasmainlyfmedNi3SiNi31Si12phase.ItcanbeNi3Siphaserefinethedendrite.(2)Effectofh

7、omogenizationtemperatureissuperitotime.TheadditionofSielementcelaythehomogenizationprocessofthealloy.WiththeincreasingoftheSiadditionthedelayedeffectismeobvious.TheSiphaseisstablefromthebeginningtoendoftheHomogenizationt

8、reatment.AfteraddedSialloyitshomogenizationkiicshomogenizationkiicsequationis)6.44(122LtDInQRToπ=.AlthoughHomogenizationtreatmentcaneliminatealloysdendritesegregationbutstillcannotmeettherequirementsofcoldrolledcogging.(

9、3)ThecoldrollingrateofthealloywithoutadditionSielementiscontenttotherequirementsofcoldrolledcoggingafter780℃f24unifmcoolinginwater.Itscoldrollingrateupto30%.Effectofsolutiontemperatureisgreaterthantime.After800℃f1hsoluti

10、ontreatmenttheγphasecanbedissolved.Ni17Sn3phasealittleγphasesmayaffectthesubsequentcoldrollingprocessofthealloy.Thealloywasagedtreatmentat400℃f4haftercoldrolling50%rate.Itshardnessvalueconductivitycanupto280HB17%IACSresp

11、ectively.(4)DuringsolutiontreatmenttheadditionSimainlyfmNi3SiNi31Si12phaseinthealloygrainboundary.Ni3SiNi31Si12phaseblockthemobileofgrainboundaryedgecontributetotheinhibitionofgraingrowth.Withtheincreaseofsolutiontempera