Cov kev sib nqus dab tsi suav nrog hauv cov khoom siv mus tas li?
Kev ua yeeb yam tseem ceeb muaj xws li remanence (Br), sib nqus induction coercivity (bHc), intrinsic coercivity (jHc), thiab cov khoom siv hluav taws xob siab tshaj plaws (BH) Max.Tsuas yog cov ntawd, muaj ntau yam kev ua yeeb yam: Curie Temperature (Tc), Ua Haujlwm Kub (Tw), qhov kub thiab txias coefficient ntawm remanence (α), kub coefficient ntawm intrinsic coercivity (β), permeability rov qab ntawm rec(μrec) thiab demagnetization nkhaus rectangularity (Hk/jHc).
Lub zog magnetic teb yog dab tsi?
Xyoo 1820, tus kws tshawb fawb HCOersted hauv Denmark pom tias rab koob nyob ze ntawm cov hlau uas muaj qhov cuam tshuam tam sim no, uas qhia txog kev sib raug zoo ntawm hluav taws xob thiab hlau nplaum, ces, Electromagnetics tau yug los.Xyaum qhia tau hais tias lub zog ntawm lub magnetic teb thiab tam sim no nrog tam sim no infinite hlau generated nyob ib ncig ntawm nws yog proportional rau qhov loj, thiab yog inversely proportional rau qhov deb ntawm cov hlau.Nyob rau hauv SI unit system, lub ntsiab txhais ntawm nqa 1 amperes ntawm tam sim no infinite xaim ntawm qhov deb ntawm 1 / hlau (2 pi) magnetic teb zog meters deb yog 1A / m (ib / M);ua kev nco txog Oersted qhov kev pab cuam rau electromagnetism, nyob rau hauv chav tsev ntawm CGS system, lub ntsiab lus ntawm nqa 1 amperes ntawm tam sim no infinite conductor nyob rau hauv lub magnetic teb zog ntawm 0.2 xaim nrug deb yog 1Oe cm (Oster), 1 / (1Oe = 4 PI) * 103A / m, thiab magnetic teb lub zog feem ntau yog qhia hauv H.
Dab tsi yog qhov sib nqus polarization (J), dab tsi yog qhov magnetization ntxiv dag zog (M), qhov sib txawv ntawm ob yog dab tsi?
Cov kev tshawb fawb sib nqus niaj hnub no qhia tau hais tias txhua qhov sib nqus tshwm sim los ntawm qhov tam sim no, uas yog hu ua magnetic dipole.Qhov siab tshaj plaws torque ntawm magnetic teb nyob rau hauv lub tshuab nqus tsev yog lub magnetic dipole lub sij hawm Pm ib chav tsev sab nraud magnetic teb, thiab lub magnetic dipole lub sij hawm ib chav tsev ntim ntawm Cov khoom yog J, thiab SI unit yog T (Tesla).Lub vector ntawm lub sijhawm sib nqus ntawm ib chav tsev ntim ntawm cov khoom yog M, thiab lub sijhawm sib nqus yog Pm / μ0, thiab SI unit yog A / m (M / m).Yog li, kev sib raug zoo ntawm M thiab J: J = μ0M, μ0 yog rau lub tshuab nqus tsev permeability, hauv SI unit, μ0 = 4π * 10-7H / m (H / m).
Dab tsi yog qhov sib nqus induction siv (B), qhov sib nqus flux ceev (B), kev sib raug zoo ntawm B thiab H, J, M yog dab tsi?
Thaum lub magnetic teb raug siv rau txhua qhov nruab nrab H, qhov sib nqus qhov sib nqus hauv qhov nruab nrab tsis sib npaug rau H, tab sis qhov sib nqus ntawm H ntxiv rau qhov sib nqus nruab nrab J. Vim tias lub zog ntawm cov hlau nplaum hauv cov khoom yog pom los ntawm cov hlau nplaum. teb H los ntawm qhov nruab nrab ntawm induction.Txhawm rau sib txawv nrog H, peb hu nws lub magnetic induction nruab nrab, denoted li B: B = μ0H + J (SI unit) B = H + 4πM (CGS units)
Chav tsev ntawm magnetic induction siv B yog T, thiab CGS chav tsev yog Gs (1T = 10Gs).Sib nqus qhov tshwm sim tuaj yeem sawv cev los ntawm cov kab sib nqus, thiab sib nqus induction B tuaj yeem txhais tau tias yog sib nqus flux ntom.Sib nqus induction B thiab sib nqus flux ceev B tuaj yeem siv dav hauv lub tswv yim.
Dab tsi yog hu ua remanence (Br), dab tsi yog hu ua magnetic coercive force (bHc), dab tsi yog intrinsic coercive force (jHc)?
Magnet magnetic field magnetization kom saturation tom qab tshem tawm ntawm sab nraud magnetic teb nyob rau hauv lub xeev kaw, cov hlau nplaum magnetic polarization J thiab sab hauv magnetic induction B thiab yuav tsis ploj vim qhov ploj ntawm H thiab sab nraud magnetic teb, thiab yuav tuav ib tug tej yam muaj nuj nqis.Tus nqi no yog hu ua residual magnetic induction magnet, hu ua remanence Br, SI unit yog T, CGS unit yog Gs (1T = 10⁴Gs).Lub demagnetization nkhaus ntawm cov hlau nplaum tas mus li, thaum qhov rov qab hlau nplaum H nce mus rau tus nqi ntawm bHc, qhov sib nqus induction ntawm B hlau nplaum yog 0, hu ua H tus nqi ntawm cov khoom sib nqus rov qab magnetic coercivity ntawm bHc;Nyob rau hauv lub rov qab magnetic teb H = bHc, tsis qhia lub peev xwm ntawm sab nraud hlau nplaum flux, lub coercivity ntawm bHc characterization ntawm cov khoom sib nqus mus tas li los tiv thaiv sab nraud rov qab magnetic teb los yog lwm yam demagnetization nyhuv.Coercivity bHc yog ib qho tseem ceeb ntawm kev tsim hluav taws xob sib nqus.Thaum qhov rov qab magnetic teb H = bHc, txawm hais tias cov hlau nplaum tsis qhia cov hlau nplaum sib nqus, tab sis qhov sib nqus ntawm cov hlau nplaum J tseem yog tus nqi loj nyob rau hauv thawj qhov kev taw qhia.Yog li ntawd, cov khoom sib nqus sib nqus ntawm bHc tsis txaus los ua tus yam ntxwv ntawm cov hlau nplaum.Thaum rov qab magnetic teb H nce mus rau jHc, lub vector micro sib nqus dipole hlau nplaum sab hauv yog 0. Tus nqi rov qab magnetic teb yog hu ua intrinsic coercivity ntawm jHc.Coercivity jHc yog lub cev tseem ceeb ntawm cov khoom siv hlau nplaum ruaj khov, thiab nws yog cov yam ntxwv ntawm cov khoom sib nqus mus tas li los tiv thaiv sab nraud rov qab sib nqus teb lossis lwm yam demagnetization effect, kom muaj qhov tseem ceeb ntawm nws qhov qub magnetization peev xwm.
Qhov khoom siv hluav taws xob siab tshaj plaws (BH) m yog dab tsi?
Nyob rau hauv BH nkhaus ntawm demagnetization ntawm cov khoom sib nqus mus tas li (ntawm ob lub quadrant), qhov sib txawv ntawm cov hlau nplaum sib txawv yog nyob ntawm kev ua haujlwm sib txawv.BH demagnetization nkhaus ntawm ib qho taw tes ntawm Bm thiab Hm (kab rov tav thiab ntsug kev sib koom tes) sawv cev rau qhov loj ntawm cov hlau nplaum thiab qhov sib nqus induction siv thiab cov hlau nplaum ntawm lub xeev.Lub peev xwm ntawm BM thiab HM ntawm tus nqi tseeb ntawm cov khoom Bm * Hm yog sawv cev ntawm lub xeev ntawm cov hlau nplaum sab nraud ua haujlwm, uas yog sib npaug rau lub zog sib nqus khaws cia hauv cov hlau nplaum, hu ua BHmax.Cov hlau nplaum nyob rau hauv lub xeev ntawm tus nqi siab tshaj plaws (BmHm) sawv cev rau cov hlau nplaum sab nraud muaj peev xwm ua haujlwm, hu ua cov khoom siv hluav taws xob siab tshaj plaws ntawm cov hlau nplaum, lossis cov khoom siv hluav taws xob, uas yog (BH) m.BHmax unit hauv SI system yog J / m3 (joules / m3), thiab CGS system rau MGOe, 1MGOe = 10² / 4π kJ / m3.
Curie kub (Tc), dab tsi yog qhov kub thiab txias ua haujlwm ntawm cov hlau nplaum (Tw), kev sib raug zoo ntawm lawv?
Curie kub yog qhov kub ntawm qhov kev sib nqus ntawm cov khoom sib nqus yog txo mus rau xoom, thiab yog lub ntsiab lus tseem ceeb rau kev hloov pauv ntawm ferromagnetic los yog ferrimagnetic cov ntaub ntawv rau hauv cov khoom sib nqus.Curie kub Tc tsuas yog muaj feem xyuam rau cov khoom muaj pes tsawg leeg thiab tsis muaj kev cuam tshuam rau micro-structure ntawm cov khoom.Ntawm qhov kub thiab txias, cov khoom sib nqus ntawm cov khoom sib nqus mus tas li tuaj yeem raug txo los ntawm ib qho kev qhia tshwj xeeb piv nrog rau hauv chav tsev kub.Qhov ntsuas kub yog hu ua qhov ntsuas kub ua haujlwm ntawm cov hlau nplaum Tw.Qhov loj ntawm qhov sib nqus zog txo yog nyob ntawm daim ntawv thov ntawm cov hlau nplaum, yog tus nqi tsis tau txiav txim siab, tib lub hlau nplaum ruaj khov nyob rau hauv cov ntawv thov sib txawv muaj qhov sib txawv ua haujlwm kub Tw.Curie kub ntawm Tc magnetic khoom sawv cev rau txoj kev xav ntawm kev khiav hauj lwm kub txwv ntawm cov khoom.Nws yog ib qho tsim nyog sau cia tias kev ua haujlwm Tw ntawm ib qho hlau nplaum ruaj khov tsis yog tsuas yog cuam tshuam nrog Tc, tab sis kuj tseem cuam tshuam nrog cov khoom sib nqus ntawm cov hlau nplaum, xws li jHc, thiab lub xeev ua haujlwm ntawm cov hlau nplaum hauv cov hlau nplaum sib nqus.
Dab tsi yog qhov sib nqus permeability ntawm cov hlau nplaum ruaj khov (μrec), J demagnetization nkhaus squareness (Hk / jHc), lawv txhais li cas?
Lub ntsiab lus ntawm demagnetization nkhaus ntawm BH hlau nplaum ua hauj lwm point D reciprocating hloov kab rov qab hlau nplaum dynamic, txoj kab nqes ntawm txoj kab rau qhov rov qab permeability μrec.Obviously, rov qab permeability μrec characterizes stability ntawm cov hlau nplaum nyob rau hauv dynamic kev ua hauj lwm tej yam kev mob.Nws yog qhov squareness ntawm cov hlau nplaum ruaj khov BH demagnetization nkhaus, thiab yog ib qho tseem ceeb ntawm cov khoom sib nqus ntawm cov hlau nplaum ruaj khov.Rau sintered Nd-Fe-B hlau nplaum, μrec = 1.02-1.10, qhov me me ntawm μrec yog, qhov zoo dua qhov ruaj khov ntawm cov hlau nplaum nyob rau hauv kev ua haujlwm zoo.
Dab tsi yog qhov sib nqus Circuit Court, dab tsi yog magnetic circuit qhib, kaw-circuit xeev?
Cov hlau nplaum hluav taws xob raug xa mus rau ib qho chaw tshwj xeeb hauv qhov sib txawv ntawm huab cua, uas yog sib xyaw ua ke los ntawm ib lossis ntau qhov ntawm cov hlau nplaum ruaj khov, cov khoom nqa tam sim no, hlau raws li cov duab thiab qhov loj me.Hlau tuaj yeem yog cov hlau ntshiab, cov hlau tsis tshua muaj hlau, Ni-Fe, Ni-Co alloy nrog cov ntaub ntawv siab permeability.Cov hlau mos, tseem hu ua yoke, nws plays lub flux tswj ndlwg, nce hauv zos sib nqus induction siv, tiv thaiv los yog txo cov hlau nplaum to, thiab ua kom lub zog ntawm cov khoom ntawm lub luag hauj lwm nyob rau hauv lub magnetic Circuit Court.Lub xeev sib nqus ntawm ib qho hlau nplaum feem ntau yog hu ua lub xeev qhib thaum tsis muaj hlau mos;Thaum cov hlau nplaum nyob hauv qhov hluav taws xob hluav taws xob tsim los ntawm cov hlau mos, cov hlau nplaum tau hais tias nyob hauv lub xeev kaw.
Dab tsi yog cov khoom siv ntawm sintered Nd-Fe-B hlau nplaum?
Cov yam ntxwv ntawm sintered Nd-Fe-B hlau nplaum:
| Bending zog / MPa | Compression zog / MPa | Hardness / Hwv | Yong Modulus /kN/mm2 | Elongation /% |
| 250-450 | 1000-1200 Nws | 600-620 | 150-160 : kuv | 0 |
Nws tuaj yeem pom tau tias sintered Nd-Fe-B hlau nplaum yog cov khoom siv tawv tawv.Thaum lub sij hawm txheej txheem ntawm machining, sib sau ua ke thiab siv cov hlau nplaum, nws yog ib qho tsim nyog yuav tsum tau ua tib zoo saib xyuas kom tsis txhob muaj cov hlau nplaum los ntawm kev cuam tshuam loj heev, kev sib tsoo, thiab kev ntxhov siab ntau dhau, kom tsis txhob tawg lossis tawg ntawm cov hlau nplaum.Nws yog ib qho tseem ceeb uas cov hlau nplaum sib nqus ntawm sintered Nd-Fe-B hlau nplaum muaj zog heev hauv lub xeev magnetized, tib neeg yuav tsum tau saib xyuas lawv tus kheej kev nyab xeeb thaum ua haujlwm, tiv thaiv cov ntiv tes nce los ntawm lub zog nqus.
Dab tsi yog qhov cuam tshuam rau qhov tseeb ntawm sintered Nd-Fe-B hlau nplaum?
Cov yam tseem ceeb uas cuam tshuam rau qhov tseeb ntawm sintered Nd-Fe-B hlau nplaum yog nws cov khoom siv, cov cuab yeej siv thiab kev siv tshuab, thiab cov txheej txheem ntawm tus neeg teb xov tooj, thiab lwm yam. Tsis tas li ntawd, micro-structure ntawm cov khoom muaj kev cuam tshuam zoo. lub machining precision ntawm cov hlau nplaum.Piv txwv li, cov hlau nplaum nrog lub ntsiab theem coarse nplej, nto nws muaj pitting ntawm machining xeev;hlau nplaum txawv txav loj hlob, nto machining xeev yog nquag muaj ntsaum qhov;qhov ntom, muaj pes tsawg leeg thiab kev taw qhia tsis sib xws, qhov loj ntawm chamfer yuav tsis sib npaug;hlau nplaum nrog cov ntsiab lus oxygen siab dua yog nkig, thiab nws yooj yim rau chipping lub kaum sab xis thaum lub sijhawm machining;Cov hlau nplaum tseem ceeb theem ntawm cov nplej ntxhib thiab Nd nplua nuj theem faib tsis zoo ib yam, cov txheej txheem plating adhesion nrog lub substrate, txheej thickness uniformity, thiab corrosion kuj ntawm txheej yuav ntau tshaj lub ntsiab theem ntawm nplua nplej thiab uniform faib ntawm Nd. nplua nuj theem sib nqus lub cev.Txhawm rau kom tau txais cov khoom lag luam zoo sintered Nd-Fe-B hlau nplaum, cov khoom siv tsim khoom, machining engineer thiab cov neeg siv yuav tsum sib txuas lus thiab koom tes nrog txhua tus.