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《mnzn功率鐵氧體材料直流疊加特性研究》由會(huì)員上傳分享，免費(fèi)在線閱讀，更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫(kù)。
1、ABSTRACTABSTRACTTheelectronicdevicesofsmalllightweightandhighreliabilityarebadlyinneedofminiaturizedswitchingpowersupplymoduleswithhighefficiencyandreliability.Asthecoresoftheswitchingpowersupplies,MnZnpowerferritecoresarethemajorcomponentofthevolumeandweight,playtheroleofpower
2、transmissionandtransformation,andmusthavehighinitialpermeability(μi),highsaturationinductiondensity(Bs)andlowcoreloss(Pcv)underhightemperature.Inthecircuitsystemcurrently,mostelectronicdevicesworkproperlyunderalternatingsignal,atthesametimeneedtocarryacertainDCsignal.TheMnZnfer
3、ritecoreswhichappliedtothecircuitsystemarethemaincarrierofAC/DCsignal,thecarryingcapacityofDCsuperpositioncharacteristicsdirectlyaffecttheefficiencyandreliabilityofthepowersystem.Basedontheexistingresearches,theinfluencesofcompositions,addtives,andprocessesonthetemperaturedepen
4、denceofmagneticpropertiesandDCsuperpositioncharacteristicswerestudied.Inthestudyofmainformula,forthecompositionofMn0.867-xZn0.133Fe2+xO4,the2+appropriateconcentrationofFeionscanhelptoobtaintheappropriatesecondarymaximumpeaktemperatureofpermeabilityμiandthepointoftheminimumPcv,a
5、ndcanalsohelptoimprovetheDCsuperpositioncharacteristic.Forthecompositionof2+Mn0.9-xZnxFe2.1O4,theappropriateZnionsconcentrationcanhelptoimprovetheinitialpermeabilityandobtainmoreexcellentDCsuperpositioncharacteristics.2+Inthestudyofadditives,Coionshaveapositivecontributiontothe
6、magnetocrystallineanisotropyconstant,makethesecondpeakofpermeabilityandvalleypointoftemperaturemovetolowtemperature.WiththeincreaseofCo2O3from0wt%to0.25wt%,theΔB（Bs-Br）increaseandtheDCsuperpositioncharacteristicsofμΔ2+andPcvareimproved.TheadditiveofNiOcanleadtoadecreaseofFeions
7、concentration,makethesecondpeakofpermeabilityandvalleypointoftemperaturemovetohightemperature,theΔBincreasesfirstandthendecreases,theDCsuperpositioncharacteristicsobtaintheoptimalwhentheappropriateamountis0.02wt%.WiththeincreaseofV2O5from0wt%to0.25wt%,thesinteringdensity(d1)and
8、Bsincreasesfirstandthendecreases,theDCsuperpositioncha
