Ferrite Block Magnet

Ferrite Block Magnet

Hais txog lub hauv paus ntawm ferromagnetism ntawm ferrite cov ntaub ntawv, nws tsis yog tsim los ntawm kev sib pauv ncaj qha ntawm electron spin ntawm ib sab sib nqus atoms zoo li cov hlau nplaum ntawm cov hlau nplaum hlau, tab sis qhov kev ncua deb ntawm ob magnetic ions yog ntev, thiab oxygen ions yog sandwiched nyob rau hauv. nruab nrab. Qhov tseeb, kev sib pauv ntawm electron spin uas tsim ferromagnetism yog tsim vim muaj cov pa oxygen ions. Hom kev pauv no yog hu ua super pauv hauv txoj kev xav ntawm ferromagnetism. Vim yog cov txiaj ntsig ntawm kev sib pauv super, lub sijhawm sib nqus ntawm cov hlau nplaum sib nqus ntawm ob sab ntawm cov pa oxygen ion tau teem rau cov lus qhia sib txawv, thiab cov tshuaj tiv thaiv ntawm ntau cov hlau oxides los ntawm qhov no. Yog hais tias lub sij hawm sib nqus txheej txheem nyob rau hauv opposite lus qhia tsis sib npaug zos thiab muaj residual sib nqus lub sij hawm, ces hom magnetism no hu ua ferrimagnetism, los yog ferrite magnetism.

Txij li thaum muaj ntau txoj haujlwm txheeb ze ntawm cov pa ions thiab sib nqus ions hauv cov ntaub ntawv ferrite, muaj ntau dua lossis tsawg dua kev sib pauv hloov pauv ntawm lawv. Cov kev tshawb fawb tau pom tias thaum qhov kev ncua deb ntawm oxygen ions thiab hlau ions nyob ze, thiab lub kaum sab xis ntawm magnetic ions thiab oxygen ions yog txog 180 degree, cov nyhuv superexchange yog qhov muaj zog tshaj. Cov kev taw qhia ntawm cov hlau nplaum ions nyob rau hauv ferrite yog tsuas yog raws li qhov muaj zog super-pauv nyhuv. Yog li ntawd, cov khoom sib nqus ntawm cov ntaub ntawv ferrite tsis yog tsuas yog cuam tshuam nrog cov qauv siv lead ua, tab sis kuj muaj feem xyuam rau kev faib cov hlau nplaum ions hauv cov qauv siv lead ua. Hloov cov sib nqus ions los yog nonmagnetic ions nyob rau hauv ferrite tuaj yeem hloov pauv cov khoom sib nqus ions hauv cov qauv siv lead ua.

Tsis tas li ntawd, thaum lub sij hawm kev npaj ferrite, cov txheej txheem sintering kuj muaj kev cuam tshuam rau kev faib cov hlau nplaum ions. Yog li ntawd, txhawm rau txhawm rau nkag siab cov yam ntxwv ntawm cov khoom siv ferrite, nws yog ib qho tsim nyog kom nkag siab txog cov qauv siv lead ua ntawm ntau yam ferrite; kev faib cov hlau ions hauv cov qauv siv lead ua; thiab yuav hloov pauv lawv li cas.