Keeb Kwm Ntawm Cov Khoom Siv Sib Nqus Soft

Puas tau txij li Michael Faraday tau qhia txog electromagnetic induction hauv 1831, tau muaj kev hloov pauv txuas ntxiv ntawm cov khoom siv hlau nplaum. Faraday lub ntuj xaiv ntawm cov khoom tseem ceeb yog hlau, uas muaj qhov siab tshaj plaws chav tsev kub M_sntawm tej yam ntxiv rau qhov loj μ_r, thiab qis H_c. Txawm li cas los xij, txawm tias nyob rau hauv cov khoom siv yooj yim uas muaj ib lub ntsiab lus tseem muaj chaw rau kev txhim kho loj heev.

Nws tau pom tias annealing hlau tsis tsuas yog txhim kho nws cov khoom siv kho tshuab, tab sis kuj txo nws cov coercivity los ntawm kev ntxhov siab, ua kom nws zoo dua rau kev siv hauv inductive daim ntaub ntawv. Nrhiav kev ua tau zoo dua, cov kws tshawb fawb thiab cov kws tsim qauv tau nrhiav txoj hauv kev los txhim kho cov khoom ntawm cov hlau mos.

Nyob rau xyoo 1900, Robert Hadfield, tus kws tshaj lij metallurgist los ntawm Askiv, tau tsim cov hlau tsis muaj zog silicon los ntawm kev ntxiv txog 3% silicon rau hlau thiab nce nws cov hluav taws xob tiv thaiv (p) thaum tseem nce μ_r. American metallurgist Norman Goss invented grainoriented silicon steel nyob rau hauv 1933 los ntawm kev txhawb nqa grain loj hlob raws li ib tug crystalline kev taw qhia ntawm tsawg anisotropy, nce μ_r, txawm ntxiv. Txawm tias niaj hnub no, silicon (los yog hluav taws xob) steels account rau ib feem loj ntawm lub ntiaj teb no mos hlau nplaum ua lag luam vim lawv siab M._sthiab tus nqi qis.

Cov kev siv ntau tshaj plaws rau silicon steel yog cov loj-teev transformers (grain-oriented silicon steel) thiab cov tshuab hluav taws xob (isotropic nonnoriented silicon steel yog nyiam rau cov tshuab tig), qhov uas nws cov nqi pheej yig yog qhov txiaj ntsig loj.

Txawm li cas los xij, qis(-, 0.5 μohm.m) ua rau silicon steels poob ntawm qhov siab. Tsis ntev los no, cov tuam txhab hluav taws xob steel tau tsim txoj hauv kev los ua kom cov ntsiab lus silicon ntawm lawv cov hlau mus txog 6.5% siv cov txheej txheem tshuaj vapor deposition (CVD). Txoj kev no ncemus rau 0.82 μΩ.m tab sis tseem tawm ntawm lwm cov ntaub ntawv raws li kev xaiv zoo dua rau cov khoom siv hluav taws xob ntau zaus thiab cov tshuab hluav taws xob sib hloov ceev.

Nyob rau xyoo 1910, Gustav Elmen ntawm Tswb Laboratories tau sim nrog nickel-hlau alloys thiab nrhiav tau cov npib tsib xee-nplua nuj (78%) permalloy muaj pes tsawg leeg. Ib qho txiaj ntsig tseem ceeb ntawm permalloy yog nws qhov siab μ_r, (txog 100, 000). Nickel-hlau alloys tseem siv nyob rau hauv qee qhov tshwj xeeb inductive daim ntawv thov niaj hnub no tab sis tsis muaj nyob rau hauv cov khoom siv hluav taws xob thiab cov tshuab hluav taws xob vim tias lawv muaj qhov poob siab tam sim no, thiab qhov sib ntxiv ntawm nickel txo M._s. Nrog rau qhov sib ntxiv ntawm me me ntawm molybdenum (2%) rau permalloy, molypermalloy hmoov (MPP) tuaj yeem tsim. MPP yog siv los tsim cov hmoov poob qis tshaj plaws.

Thaum xyoo 1940s magnetically soft ferrites tau tsim los ntawm JL Snoek . Cov ntaub ntawv no muaj kev sib tw vim lawv cov hluav taws xob muaj zog heev (10 - 10⁸μohm.m), uas ua rau lawv muaj txiaj ntsig zoo ntawm kev tiv thaiv eddy tam sim no poob.

Tsis tas li ntawd, vim tias lawv tau tsim nrog cov txheej txheem ceramic thiab cov khoom siv ntau, cov khoom ferrite tuaj yeem tsim tau ntawm tus nqi qis heev. Lub siab

thiab kev pheej yig ntawm cov ferrites mos ua rau cov ntaub ntawv no nyob rau hauv kev thov siab rau inductive daim ntaub ntawv, nrog rau cov uas muaj zaus. Qhov tseeb, lawv feem ntawm kev lag luam thoob ntiaj teb hauv cov hlau nplaum mos yog qhov thib ob rau silicon steel. Lawv raug kev txom nyem los ntawm qhov qis M_s. (ze li ib feem peb ntawm cov hlau silicon), uas txwv lub zog ceev ntawm inductive ntsiab uas muaj ferrite core.

Nyob rau hauv 1967, ib chav kawm tshiab ntawm cov ntaub ntawv, amorphous alloys, tau tsim. Los ntawm nruab nrab xyoo 1970, kev txaus siab rau hlau thiab cobalt raws li amorphous alloys tau nce thiab lawv pib nrhiav lawv txoj hauv kev siv. Los ntawm kev tshem tawm txhua qhov kev txiav txim ntev ntev, kev sib koom tes tau txo qis hauv cov hlau no.

Xyoo 1988, cov kws tshawb fawb ntawm Hitachi suav nrog Nb thiab Cu additives thiab ntxiv cov kauj ruam annealing rau kev tsim cov amorphous alloys los tsim cov khoom me me thiab ze ze ntawm crystallites ntawm hlau los yog cobalt (ntawm qhov kev txiav txim ntawm 10 nm inch) nyob rau hauv ib tug matrix ntawm amorphous khoom. Qhov no yog qhov pib ntawm nanocrystalline mos magnetic alloys. Qhov tsim ntawm kev hloov pauv ntawm cov hlau crystallites txo cov eddy tam sim no poob ntawm cov ntaub ntawv no piv rau amorphous alloys. Ob qho tib si amorphous thiab nanocrystalline alloys tau txais kev lag luam feem ntau hauv cov khoom siv hluav taws xob thiab cov tshuab hluav taws xob niaj hnub no vim lawv qhov poob qis thiab kev sib tw M._s.

Txawm hais tias tus nqi pib ntau dua li silicon steel, cov alloys siab heev tuaj yeem txo tag nrho cov nqi hluav taws xob thiab cov tshuab hluav taws xob hauv lub neej, ua tsaug rau kev txo qis.

Nyob rau xyoo 1990s, hmoov cores (tseem hu ua mos magnetic composites lossis SMCs) tau txais kev lees paub hauv qee cov ntawv thov sib nqus. Cov ntaub ntawv no muab cov khoom sib nqus sib nqus, nyob qhov twg ntawm kwv yees li 1 mus rau 500 gm inch, thiab lub tsho tiv no los yog sib tov nrog cov khoom siv insulating ua ntej sib sau ua ke nrog kev kub siab (MPa rau txawm tias GPa pressures).

Thaum tshav kub kub kuj tseem tuaj yeem siv tau thaum lub sij hawm los yog tom qab densification los txhim kho cov khoom sib nqus. Cov khoom sib nqus feem ntau yog Fe hmoov tab sis tuaj yeem muaj cov hlau nplaum xws li MPP (hais ua ntej), Fe-P, Fe-Si, lossis Fe-Co. Vim tias cov txheej txheem insulating thiab tsis sib nqus matrix, cov ntaub ntawv no muaj qhov sib txawv ntawm huab cua uas txwv lawv μ_rmus rau ntau yam ntawm 100 mus rau 500. Txawm li cas los, lub insulating matrix kuj boosts lawv.

(10^-3rau 10^-1µohm•m), txo eddy tam sim no poob.

SMCs tseem tuaj yeem raug nias rau hauv ntau qhov kawg geometries yam tsis tas yuav tsum muaj kev siv tshuab (net-shaping), uas tuaj yeem txo cov nqi tsim khoom. Lawv cov xwm txheej isotropic, tus nqi qis, thiab muaj peev xwm ua kom zoo li qhov sib txawv tau ua rau SMCs muaj kev vam meej hauv kev tig tshuab hluav taws xob.

Cov keeb kwm luv luv ntawm cov khoom siv hlau nplaum uas tau piav saum toj no tsis txhais tau tias tag nrho. Hloov chaw, peb lub hom phiaj yog tsom mus rau cov ntaub ntawv uas tau ua thiab tseem yuav muaj kev sib tw rau kev tsim cov khoom sib nqus ntawm cov khoom siv hluav taws xob thiab cov tshuab hluav taws xob. Kev ntsuas kev ua tau zoo xws li M_sthiab kev poob tseem ceeb heev. Txawm li cas los xij, vim tias cov khoom sib nqus mos yuav tsum tau siv ntau ntau, qhov tseem ceeb ntawm tus nqi tsis tuaj yeem tsis quav ntsej. Vim li no, cov ferrites mos tseem tseem yog cov khoom siv sib tw ntawm cov zaus. Vim tias lawv cov kev ua tau zoo heev ntawm cov zaus, cov amorphous thiab nanocrystalline alloys yeej tseem yog cov ntaub ntawv tseem ceeb. Txawm hais tias silicon steels tseem ua rau feem ntau ntawm lub ntiaj teb kev ua lag luam rau cov khoom sib nqus mos, lawv cov kev siv tseem ceeb yog nyob rau hauv cov transformers loj khiav hauj lwm ntawm 50 lossis 60 Hz thiab qeeb rotational ceev hluav taws xob tshuab.