简介:EffectofLa-richrareearthoneutecticmicrostructureinA1-2%Fealloywasstudied.WhentheadditionofREissmall,a-A1phaseisintheformofcellulardendrite.WiththeincreaseoftheadditionofRE,thenucleationandgrowthofa-A1dendritearesuppressed,andeutecticAl3Fephaseisrefined.WhentheadditionofREgetsto0.6%(massfrac-tion),thesizeofeutecticAl3Feincreases.Inaddi-tion,mechanismoftheeffectofmixedREoneutecticmorphologyofA1-2%Fealloyisexplored.
简介:介绍了ER—1型卷耳机整机构成及其各部分功能,阐明了运行中的各种故障现象及其排除方法。
简介:EffectofMnsubstitutionforFeincubicLavesZr0.1Tb0.9(Fe1-xMnx)2andY0.1Tb0.9(Fe1-xMnx)2com-poundsispresented.Similarresultsinbothsystemsareobtained:ThestructureandthemagnetismofTbFe2arebothinfluencedslightlybyasmallamountofYorZrsubstitutionforTb;Withincreasingxvalue,thelatticeconstantincreasesmonotonously;theCurietemperaturedecreaseslinearly;whilesaturationmagnetizationincreaseslinearly.ForthesmallamountofMnsubstitutionforFeinbothsystems,magnetostrictionissignificantlylargerthanthatinthepureironalloys.Thelargestmagnetostrictionof|γ‖-|γ|=2200×10-6atmagneticfieldof2×107/4πA/misobtainedforY0.1Tb0.9(Fe0.95Mn0.052.
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简介:ThemeasurementsoftemperaturedependenceofthemagneticsusceptibilityofLa1-xSrxCoO3perovskiteoxidesatdifferentSrdoping(0≤x≤0.5)andannealingtemperaturewerepresented.Forthesamplewithx=0.1,ashoulderwasobservedaround150K,andapeakwhichisonefeatureofspinglassappearedaround50Kinthecurveofsusceptibilityversustemperature.Thehigh-temperature(250~420K)susceptibilityfitswellwithCurie-Weisslawforallsamples.WeissconstantandeffectivemagneticmomentweredeterminedandtheirvariationswithSrdopingandoxygenannealingconditionwereobtained.TheWeissconstantincreasesmonotonouslywithSrcontentforx>0.2.Thevaluesofeffectivemomentswereinterpretedwiththespinstateofcobaltions.Studiesonthesusceptibilitiesofthesampleswithx=0.2underdifferentpreparationtemperaturesandannealingtemperaturesshowthattherisingofsinteringtemperatureandannealingtemperaturewillincreasethepara-ferromagnetictransitiontemperature,andreducetheeffectivemomenttonormalvalue.OurresultshowsthatbothCo3+andCo4+ionsshouldbeinISstateafterannealingandtheoxygenannealingcausesthetransitionofCo3+spinstatefromHStoIS.