(Photo: Honda)
Raws li lub npe qhia, PM synchronous hom, uas yog lub ntsiab tsav lub cev muaj zog, siv cov hlau nplaum ruaj khov. Neodymium hlau nplaum yog siv rau cov hlau nplaum no vim lawv qhov sib npaug ntawm lub zog sib nqus thiab ua haujlwm ntev, thiab lo lus "tsis tshua muaj ntiaj teb" feem ntau hnov nyob ib ncig ntawm lawv. Cov khoom xyaw no siv rau dab tsi?
Neodymium hlau nplaum zoo li tau dhau los ua ntau heev. Txhawm rau muab nws kom raug, nws yog ib hom hlau nplaum uas tsis tshua muaj hauv ntiaj teb, thiab nws yog cov hlau nplaum ua los ntawm sintering cov hmoov txheej ntawm Nd2Fe14B (neodymium / hlau / boron). Tsim los ntawm 1982 los ntawm Masato Sagawa thiab lwm tus, nws yog ib qho ntawm cov thev naus laus zis uas Nyiv txaus siab rau. Raws li ntawm 2023, nws yog qhov muaj zog tsis tshua muaj zog hlau nplaum hauv kev siv nyob rau hauv cov ntsiab lus uas muaj kev sib nqus zoo nkauj thiab kev quab yuam yog tias nws yog qis dua nyob rau hauv tshav kub ua hauj. Tshwj xeeb, thaum qhov kub nce mus txog li 315 degree (=Curie point), irreversible demagnetization tshwm sim.
Kev siv zog ua kom txias lub cev muaj zog kom nws tsis ncav cuag qhov kub ntawm 315 degrees Celsius, tab sis ib txoj kev tau tsim los ntxiv dysprosium thiab terbium los ua kom kub tsis kam. Feem ntau, cov hlau nplaum neodymium muaj cov ntsiab lus ntawm 60 feem pua ntawm hlau thiab 30 feem pua neodymium, tab sis yog tias koj ntxiv ob peb feem pua ntawm dysprosium rau qhov no, nws tau hais tias thermal demagnetization tuaj yeem txhim kho los ntawm 15 degrees Celsius rau 1 feem pua ntxiv (Wikipedia: Neodymium hlau nplaum Yog). Txawm hais tias terbium muaj cov cuab yeej uas txhim kho kev quab yuam zoo dua li dysprosium, nws yog cov hlau tsis tshua muaj dua li dysprosium, yog li dysprosium feem ntau ua lub luag haujlwm no.
Txawm li cas los xij, nws paub tseeb tias dysprosium kuj yog cov hlau tsis tshua muaj. Puas yog nws ua tau kom ua tiav ob qho kev tiv thaiv kub thiab quab yuam tsis siv cov no? Piv txwv ntawm cov tuam txhab uas ua haujlwm rau cov teeb meem no yog Honda thiab Toyota. Ob leeg tau tsom mus rau qhov tseeb tias "cov qauv sintered muaj cov qoob loo loj uas txwv nws qhov kev ua tau zoo," thiab lub tswv yim yog tias yog tias nws tau ua rau hauv cov qauv zoo heev, qhov kub tsis kam thiab kev quab yuam tuaj yeem nce ntxiv.
Yog hais tias lub cev muaj zog kub heev, cov hlau nplaum ruaj khov rotors yuav irreversibly demagnetize. Tus nqi pib yog nyob ib ncig ntawm 150 degrees raws li qhia hauv daim ntawv qhia. Txij li thaum peb tsis xav ua txhaum cov hlau nplaum neodymium kim, peb yuav tsum tau tswj lub cev muaj zog kom nws nyob ntawm qhov kub thiab txias uas siv lub tshuab cua txias. Ntxiv nrog rau cov kua-txias lub rotor thiab stator siv cov kua dej, qhov nce ntawm cov khoom tseem ceeb yog ua kom cov dej txias hauv ob theem uas siv dej-txias, uas yog ib txoj hauv kev kom ua tiav cov txiaj ntsig zoo.
