Nyob ntawm cov khoom sib nqus, cov tshuaj yog cov diamagnets, paramagnets thiab ferromagnets. Thiab nws yog cov khoom siv ferromagnetic uas muaj cov khoom tshwj xeeb uas txawv ntawm qhov seem.
Yam khoom no yog dab tsi thiab nws muaj dab tsi
Cov khoom siv ferromagnetic (los yog ferromagnet) yog ib yam khoom uas nyob rau hauv cov khoom crystalline los yog amorphous lub xeev, uas yog magnetized nyob rau hauv tsis muaj ib tug magnetic teb tsuas yog nyob rau hauv ib tug tsis tshua muaj kub tseem ceeb, piv txwv li nyob rau hauv ib tug kub hauv qab ntawm Curie point.. Qhov sib nqus susceptibility ntawm cov khoom no yog qhov zoo thiab tshaj kev sib sau. Qee cov ferromagnets tej zaum yuav muaj cov hlau nplaum sib nqus, lub zog uas yuav nyob ntawm lwm yam. Ntawm lwm yam, cov ntaub ntawv zoo li no muaj kev sib nqus zoo heev thiab muaj peev xwm ua kom lub zog sib nqus sab nraud los ntawm ntau pua txhiab zaus.
pab pawg ntawm ferromagnets
Muaj ob pawg ntawm cov khoom siv ferromagnetic tag nrho:
- Magneticly soft group. Ferromagnets ntawm pab pawg no muaj me mecov ntsuas ntawm magnetic teb lub zog, tab sis muaj zoo heev sib nqus permeability (tsawg dua 8.0 × 10 -4H / m) thiab qis hysteresis poob. Cov khoom sib nqus mos muaj xws li: permalloys (alloys nrog ntxiv ntawm npib tsib xee thiab hlau), oxide ferromagnets (ferrites), magnetodielectrics.
- Magnetically nyuaj (los yog pawg hlau nplaum nyuaj). Cov yam ntxwv ntawm cov ntaub ntawv ferromagnetic ntawm pab pawg no yog siab dua li ntawm yav dhau los. Cov khoom sib nqus muaj ob qho tib si siab magnetic teb muaj zog thiab zoo sib nqus permeability. Lawv yog cov khoom siv tseem ceeb rau kev tsim cov hlau nplaum thiab cov khoom siv uas siv lub zog quab yuam thiab yuav tsum muaj kev sib nqus zoo heev. Cov pawg hlau nplaum muaj xws li yuav luag txhua cov pa roj carbon thiab qee cov hlau hlau (cob alt, tungsten thiab chromium).
Cov khoom ntawm cov hlau nplaum mos pawg
Raws li tau hais ua ntej, pawg sib nqus mos muaj xws li:
- Permalloys, uas tsuas yog muaj hlau thiab npib tsib xee alloys. Chromium thiab molybdenum qee zaum ntxiv rau permalloys kom nce permeability. Ua kom zoo permalloys muaj siab sib nqus permeability thiab coercivity.
- Ferrites yog cov khoom siv ferromagnetic uas muaj oxides ntawm hlau thiab zinc. Feem ntau manganese lossis npib tsib xee oxides ntxiv rau cov hlau thiab zinc kom txo tau qhov tsis kam. Yog li ntawd, ferrites feem ntau yog siv los ua semiconductors rau high-frequency tam sim no.
- Magnetodielectricsyog cov hmoov sib tov ntawm hlau, magnetite los yog permalloy hmoov qhwv hauv ib zaj duab xis dielectric. Ib yam li ferrites, magnetodielectrics yog siv los ua semiconductors hauv ntau yam khoom siv: amplifiers, receivers, transmitters, etc.
Cov khoom ntawm pawg sib nqus nyuaj
Cov ntaub ntawv hauv qab no yog rau pawg hlau nplaum nyuaj:
- Carbon steels ua los ntawm cov hlau alloy thiab carbon. Nyob ntawm seb cov pa roj carbon ntau npaum li cas, muaj cov pa roj carbon tsawg (tsawg dua 0.25% carbon), nruab nrab-carbon (los ntawm 0.25 mus rau 0.6% carbon) thiab high-carbon steels (txog 2% carbon). Ntxiv rau cov hlau thiab carbon, silicon, magnesium thiab manganese kuj tseem tuaj yeem suav nrog hauv cov khoom sib xyaw ntawm cov hlau. Tab sis qhov zoo tshaj plaws thiab tsim nyog cov ntaub ntawv ferromagnetic yog cov carbon steels uas muaj tsawg kawg nkaus impurities.
- Alloys raws li lub ntiaj teb tsis tshua muaj cov ntsiab lus, xws li samarium-cob alt alloys (SmCo5 lossis Sm2Co17 compounds). Lawv muaj siab sib nqus permeability nrog qhov seem induction ntawm 0.9 T. Nyob rau tib lub sij hawm, lub magnetic teb nyob rau hauv ferromagnets ntawm hom no kuj yog 0.9 T.
- Lwm cov alloys. Cov no suav nrog: tungsten, magnesium, platinum thiab cob alt alloys.
Qhov txawv ntawm cov khoom siv ferromagnetic thiab lwm yam khoom nrog cov khoom sib nqus
Thaum pib ntawm tsab xov xwm, nws tau hais tias ferromagnets muaj cov khoom tshwj xeeb uas txawv heevlos ntawm lwm cov ntaub ntawv, thiab ntawm no yog qee qhov pov thawj:
- Tsis zoo li cov diamagnets thiab paramagnets, uas muab lawv cov khoom los ntawm ib tus neeg atoms thiab molecules ntawm cov teeb meem, cov khoom ntawm ferromagnetic yog nyob ntawm cov qauv siv lead ua.
- Cov ntaub ntawv Ferromagnetic, tsis zoo li, piv txwv li, paramagnets, muaj txiaj ntsig zoo ntawm cov hlau nplaum permeability.
- Ntxiv rau qhov permeability, ferromagnets txawv ntawm cov ntaub ntawv paramagnetic uas lawv muaj kev sib raug zoo ntawm cov hlau nplaum thiab lub zog hlau nplaum, uas muaj lub npe tshawb fawb - sib nqus hysteresis. Ntau cov ntaub ntawv ferromagnetic, xws li cob alt thiab npib tsib xee, nrog rau cov alloys raws li lawv, raug rau qhov tshwm sim zoo sib xws. Los ntawm txoj kev, nws yog qhov sib nqus hysteresis uas tso cai rau cov hlau nplaum kom tswj tau lub xeev ntawm cov hlau nplaum ntev.
- Qee cov ntaub ntawv ferromagnetic kuj muaj peev xwm hloov lawv cov duab thiab loj thaum magnetized. Qhov tshwm sim no yog hu ua magnetostriction thiab tsis yog nyob ntawm hom ferromagnet nkaus xwb, tab sis kuj tseem muaj lwm yam tseem ceeb sib npaug, piv txwv li, ntawm lub zog ntawm cov teb thiab qhov chaw ntawm crystallographic axes nrog kev hwm rau lawv.
- Lwm qhov nthuav dav ntawm cov tshuaj ferromagnetic yog lub peev xwm poob nws cov khoom sib nqus los yog, muab nws yooj yim, tig mus rau hauv paramagnet. Cov nyhuv no tuaj yeem ua tiav los ntawm cua sov cov khoom siv saum toj no lub npe Curie point, thaum hloov mus rau lub xeev paramagnetic tsis nrog rau cov kev mob tshwm sim thiab xyaum tsis pom ntawm qhov muag liab qab.qhov muag.
Teb daim ntawv thov ntawm ferromagnets
Raws li koj tuaj yeem pom, cov khoom siv ferromagnetic nyob ib qho chaw tseem ceeb hauv lub ntiaj teb niaj hnub ntawm kev siv tshuab. Nws yog siv rau hauv kev tsim khoom ntawm:
- cov hlau nplaum tas mus li;
- magnetic compasss;
- transformers thiab generators;
- hluav taws xob motors;
- ntsuas ntsuas hluav taws xob;
- receivers;
- transmitters;
- amplifiers thiab receivers;
- hard drives rau laptops thiab PCs;
- suab nrov thiab qee hom xov tooj;
- recorders.
Yav dhau los, qee cov khoom siv hlau nplaum kuj tau siv hauv xov tooj cua engineering los tsim cov kab hlau nplaum thiab cov yeeb yaj kiab.
