摘要
InordertoimproveandstabilizethemagneticpropertiesofnanocompositeNd2Fe14B/α-Femagneticalloysbyacompositionaladjustment,smallamountofDyand/orCowasaddedtoNd9Fe84B7alloys.DTAanalysisontheamorphousofthealloystookplaceasthesoftmagneticphaseswerecrystallized,andthenthehardmagneticNd2Fe14Bwasprecipitatedfromthem.Whileα-Feandametastable1:7(TbCu7-type)phasewereformedsimultaneouslyinDyandCo-freealloys,theywerecrystallizedseparatelyatdifferenttemperaturesafterDyorCowasadded.ThisphaseseparationoccurredmoreclearlyintheDy-treatedalloysandtheothersoftmagneticphaseFe3BwasalsostabilizedbyDyand/orCo.The1:7phasethatwasstabilizedbyDyand/orCowasnoteliminatedat700℃,decreasingmagneticpropertiesofthealloys.Itwaseventuallydisappearedabove725℃,butFe3Bwasnoteliminatedevenat750℃whenDywasaddedmorethan0.5at%orCowasaddedmorethan2.0at%.AmountofNd2Fe14BinthealloystendedtoincreaseasDyadditionincreased,whereasCoadditiondidnotleadtoanyappreciablechangeintheratioofα-FeandNd2Fe14B.Moreover,DyadditionapparentlyincreasedcoercivityofanalloywhileCoadditionhadabeneficialeffectonremanence.ThegrainsintheDytreatedalloyswereusuallyfinerthanthoseintheCo-treatedalloys.Thegrainsizeofbothα-FeandNd2Fe14Binthealloysexhibitingmr≥0.72wasintherangeof20～40nmorevenlarger50nm,whichislargerthanthetheoreticaloptimumsize(～10nm).TypicalmagneticpropertiesobtainedfromaNd7.5Dy1.5Fe82.5Co1.5B7alloyannealedfor12minat725℃wereiHc=4.85kOe,Br=11.32kG,(BH)max=15.73MGOe,andmr=0.73.
出版日期
2004年10月01日（中国期刊网平台首次上网日期，不代表论文的发表时间）
