I-Hysteresis magnetic: incazelo, izakhiwo, ukusetshenziswa okusebenzayo

I-Hysteresis iyimagnetic, i-ferroelectric, iguquguqukayo, ilula. Kubuye kwenzeke ku-biology, isayensi yesayensi, kanye nezomnotho. Futhi okuyisisekelo sale ncazelo cishe kufana. Kodwa lesi sihloko sizobhekana ngokuqondile ne-magnetic, uzofunda kabanzi mayelana nalesi simo, ukuthi kuncike nini futhi uma sibonakala. Lesi simo senziwa emayunivesithi anokugxila kwezobuchwepheshe, ikharikhulamu yesikole ayifakiwe, ngakho akubona wonke umuntu owazi ngakho.

Hysteresis magnetic

Lokhu kuncike ekutheni okungenakuphika futhi okungaqondakali kwe-index magnetization yezinto (futhi lokhu, njengokungumthetho, iyala magnetically ngamagogagethi) kusuka ensimini yangaphandle magnetic. Kulesi simo, insimu ishintsha njalo - iyancipha noma iyanda. Isizathu esiphezulu sokuba khona kwe-hysteresis kuba khona okungenani ubunamandla be-thermodynamic wombuso ongaguquki futhi ozinzile, futhi kukhona nezinguquko ezingenakuphikisana phakathi kwazo. I-hysteresis iyimbonakaliso yesigaba sokushintsha kwamagnetic sokuqala kohlobo lokuqala. Kulezi zimo, ukuguqulwa kwesigaba esisodwa kuya kwesinye kwenzeka ngenxa yezizwe ezihlelekile. Isici igrafu ebizwa ngokuthi "hysteresis loop". Ngezinye izikhathi futhi kuthiwa "i-magnetization curve".

I-hysteresis loop

Egrafini yokuthembela kwe-M ku-H, umuntu angabona:

1. Kusukela esimweni se-zero, lapho uM = 0 no-H = 0, nge-H, i-M iyanda.
2. Lapho insimu ikhula, i-magnetization iba njalo njalo futhi ilingana nenani le-saturation.
3. Uma ihlehlisa, i-reverse ishintshiwe, kodwa uma i-H = 0, i-magnetization M ayinayo. Lolu shintsho lungabonakala kusuka kwikota ye-demagnetization. Futhi uma i-H = 0, i-M ithatha inani elilingana ne-magnetization e-remanent.
4. Uma i-H yanda esikhathini -Hm ... + Hm, izinguquko ze-magnetization eceleni kwekhava lesithathu.
5. Wonke ama-curve amathathu achaza ukuthi izinqubo zihlangene ndawonye futhi zakha uhlobo loop. Nguye ochaza umphumela we-hysteresis - izinqubo ze-magnetization ne-demagnetization.

I-magnetization energy

I-loop ibhekwa njenge-asymmetrical esimweni lapho insimu maxima H1, esetshenziselwa izikhombandlela eziphambene neziphambili, azifani. Ngenhla, i-loop ichazwe, okuyinto ephawulekayo yenqubo yokuguqula i-magnetization. Kuzo, izibopho ze-quasi-equilibrium phakathi kwamagugu ka-H no-M zigcinwe. Kubalulekile ukunaka iqiniso lokuthi ukugaya amagesi noma ukudayiswa kwemithwalo yemvelo kubangelwa i-M kusuka ku-H. Futhi lokhu kuholela ekutheni wonke amandla atholakala ngento ye-ferromagnetic ngesikhathi se-magnetization ayinikeziwe Ngokuphelele phakathi nomjikelezo we-demagnetization. Futhi lo mthelela uhamba konke ekushiseni kwe-ferromagnet. Futhi i-loop yamagnetic hysteresis ivela njenge-asymmetric kulokhu.

Umumo we-Loop

Uhlobo lwe-loop luxhomeke emigqeni eminingi-amandla amakhulu, amandla omkhakha, ukutholakala kokulahlekelwa, njll. Ukwakhiwa kwamakhemikhali we-ferromagnet, isimo salo sakhiwo, izinga lokushisa, uhlamvu kanye nokusatshalaliswa kweziphambeko, nokuba khona kokucubungula (ukushisa, ukushisa ama-thermomagnetic, mechanical) nakho kunethonya elikhulu. Ngenxa yalokho, i-hysteresis ye-ferromagnet ingashintshwa ngokuhambisa izinto zokwenza izinto. Kulokhu, zonke izici zenguquko yendaba.

Ukulahleka kwe-hysteresis

Ngesikhathi ukuguqulwa kwamagnetization okuguquguqukayo kwe-ferromagnet, insimu ehlukile yamagnetic ibangela ukulahlekelwa. Futhi zakha ingxenye encane kuphela yokulahlekelwa okuphelele kwamagnetic. Uma izingodo ziba nokuphakama okufanayo (inani eliphakeme elifanayo le-magnetization M), i-loop yefomu elishintshayo ivulekile kune-static eyodwa. Lokhu kungenxa yokuthi ukulahlekelwa okusha kuhlanganiswa kuwo wonke amalahle. Lezi ukulahlekelwa okunamandla, ngokuvamile kuvumelaniswa ne- eddy yamanje, i-viscosity magnetic. Ngokulinganiselwe, ukulahlekelwa okuphawulekayo kuyatholakala nge-hysteresis.

Ama-ferromagnet wesizinda esisodwa

Uma kwenzeka ukuthi izinhlayiyana zinezinga elihlukile, inqubo yokujikeleza iyaqhubeka. Lokhu kungenxa yokuthi ukwakheka kwezizinda ezintsha akusizi ngalutho kumbono wokubuka amandla. Kodwa inqubo yokushintshanisa izinhlayiyana ivinjelwa yi-anisotropy (magnetic). Kungaba nemvelaphi ehlukile - ukwakha ekristini ngokwayo, ukuphakama ngenxa yokucindezeleka okugxile, njll). Kodwa ngosizo lwale anisotropy ukuthi i-magnetization ibanjwe insimu yangaphakathi. Kubizwa nangokuthi insimu ephumelelayo yama-magnetic anisotropy. Futhi i-hysteresis yamagnetic ivela ngenxa yokuthi izinguquko ze-magnetization ezinkomba ezimbili - ziqondisa futhi ziguquke. Phakathi nokuguqulwa kwamagnetization we-single-domain ferromagnet, kuqhuma izimbalwa eziningana. I-vector magnetization M iya enhlangothini yensimu H. Ngaphezu kwalokho, ukujikeleza kungaba okungafani noma okungenakuqhathaniswa.

Ama-ferromagnethi amaningi

Kuzo, ijika le-magnetization lakhiwe ngendlela efanayo, kodwa lapha izinqubo zihlukile. Lapho ukuguqulwa kwamagnetization kwenzeka, imingcele yezizinda ishintshiwe. Ngenxa yalokho, esinye sezizathu zokwenzeka kwe-hysteresis kungaba ukulibazisa ekuhambeni kwemingcele, kanye nokujuluka okungaqondakali. Ngezinye izikhathi (uma ama-ferromagnets enensimu enkulu kakhulu), i-hysteresis yamagnetic inqunywa ukulibala kokukhula kanye nokwakhiwa kwe-nuclei yokuvuselela. Kuvela kulezi nuclei ukuthi isakhiwo sesizinda sezinto ezikhiqizwa yi-ferromagnetic sakhiwa.

Umbono we-hysteresis

Kumele kucatshangelwe ukuthi isenzakalo se-magnetic hysteresis senziwa futhi ngokushintshanisa kwensimu H, hhayi kuphela lapho ishintsha ngokuphawulekayo nokukhulu. Lokhu kubizwa ngokuthi i-hysteresis ye-rotation magnetic futhi ifana nokushintshwa kokuqondisa kwe-magnetization M ngokushintsha kwendlela esekelwe kuyo H. Ukubonakala kwe-hysteresis yokujikeleza kwe-magnetic kubonakala futhi lapho isampula esaphansi kwesifundo ijikelezwa ngokuphathelene nensimu ehleliwe H.

Ijika le-magnetization libuye lifanise nesakhiwo semvelo sesizinda. Isakhiwo sishintsha ngokuhamba kwezinqubo zokuguqulwa kwamagnetization kanye ne-magnetization. Izinguquko zixhomeke ekunganiseni kwemingcele yezizinda ezishintshayo, kusukela emiphumeleni yensimu yangaphandle yamagnetic. Ngokuqinisekile konke okungavimbela zonke izinqubo ezichazwe ngenhla, kuguqula ama-ferromagnethi esimweni esingathuthuki futhi yisiphi isizathu sokuthi kungani i-hysteresis magnetic ivela.

Kufanele kucatshangelwe ukuthi i-hysteresis incike kwimingcele eminingi. Ukuguqulwa kwamagnetization ngethonya langezici zangaphandle - ukushisa, ukucindezeleka okukhulu, ngakho-ke kuvela i-hysteresis. Lokhu kubangela hysteresis hhayi kuphela magnetization, kodwa futhi kuzo zonke lezo zakhiwo lapho kuxhomeke khona. Njengoba kubonakala kusuka lapha, umphumela we-hysteresis ungaqaphelwa kuphela uma izinto zihlanganisiwe, kodwa nakweminye izinqubo zomzimba, ezixhunyiwe ngokuqondile noma ngokungaqondile nayo.