Yiyiphi imisebenzi yamagnetic efakwe kwizinto ezisisigxina?
Izinto eziphambili zemagnethi ziquka i-remanence (Br), i-magnetic induction coercivity (bHc), i-intrinsic coercivity (jHc), kunye nemveliso yamandla aphezulu (BH) Max.Ngaphandle kwezo, kukho ezinye izinto ezininzi ezenziwayo: iCurie Temperature(Tc), iTemperature yokuSebenza(Tw), umlinganiso wobushushu we-remanence(α), umlinganiso wobushushu we-intrinsic coercivity(β), ukubuyiswa kwe-rec(μrec) kunye noxande lwe-demagnetization curve. (Hk/jHc).
Yintoni amandla emagnethi?
Ngomnyaka we-1820, isazinzulu iHCOersted eDenmark safumanisa ukuba inaliti kufuphi nocingo olune-deflect yangoku, ebonisa ubudlelwane obusisiseko phakathi kombane kunye nemagnethi, emva koko, i-Electromagnetics yazalwa.Ukuziqhelanisa kubonisa ukuba amandla ombane wemagnethi kunye nangoku ngoku intambo engenasiphelo eyenziwe ngeenxa zonke ihambelana nobukhulu, kwaye ihambelana ngokuphambene nomgama ukusuka kwintambo.Kwinkqubo yeyunithi ye-SI, inkcazo yokuthwala i-amperes ye-1 yocingo olungapheliyo lwangoku kumgama we-1 / ucingo (2 pi) iimitha zamandla ombane wemagnethi umgama ngu-1A / m (an / M);ukukhumbula igalelo le-Oersted kwi-electromagnetism, kwiyunithi yenkqubo yeCGS, inkcazo yokuthwala i-amperes ye-1 ye-conductor yangoku engenasiphelo kumandla ombane we-0.2 wecingo umgama yi-1Oe cm (Oster), 1/ (1Oe = 4 PI) * I-103A/m, kunye namandla emagnethi adla ngokubonakaliswa kwi-H.
Yintoni i-polarization magnetic (J), yintoni i-magnetization yokuqinisa (M), yintoni umahluko phakathi kwezi zimbini?
Izifundo zemagnethi zanamhlanje zibonisa ukuba zonke iziganeko zemagnethi zivela kumbane wangoku, obizwa ngokuba yi-dipole yemagnethi. Owona mzuzu uphezulu wemagnethi yemagnethi kwivacuum ngumzuzu wemagnethi wePm kwiyunithi yangaphandle yemagnethi, kunye nomzuzu wemagnethi kwiyunithi nganye izinto eziphathekayo ngu-J, kunye neyunithi ye-SI yi-T (Tesla).I-vector yomzuzu wamagnetic kwiyunithi nganye umthamo wezinto eziphathekayo ngu-M, kunye nomzuzu wamagnetic ngu-Pm / μ0, kunye neyunithi ye-SI ngu-A / m (M / m).Ngoko ke, ubudlelwane phakathi kwe-M kunye ne-J: J = μ0M, μ0 i-vacuum permeability, kwiyunithi ye-SI, μ0 = 4π * 10-7H / m (H / m).
Yintoni i-magnetic induction intensity (B), yintoni i-magnetic flux density (B), yintoni ubudlelwane phakathi kwe-B kunye no-H, J, M?
Xa i-magnetic field isetyenziswa nakweyiphi na i-H medium, i-magnetic field intensity kwi-medium ayilingani no-H, kodwa i-magnetic intensity ye-H kunye ne-magnetic medium J. Ngenxa yokuba amandla ombane wemagnethi ngaphakathi kwezinto aboniswa yimagnethi intsimi H ngokusebenzisa i medium induction.Ukwahluka nge-H, siyibiza ngokuba yimagnethi yokungenisa, echazwa njenge-B: B= μ0H+J (iyunithi ye-SI) B=H+4πM (iiyunithi zeCGS)
Iyunithi ye-magnetic induction intensity B yi-T, kunye neyunithi yeCGS yi-Gs (1T=10Gs).Isenzeko semagnethi sinokubonakaliswa ngokucacileyo yimigca yomhlaba wemagnethi, kunye nokungeniswa kwemagnethi B kunokuchazwa njengoxinaniso lwemagnethi.Ukungeniswa kwemagneti B kunye noxinaniso lwemagnethi oluguquguqukayo B lunokusetyenziswa jikelele kwingqikelelo.
Yintoni ebizwa ngokuba yi-remanence (Br), into ebizwa ngokuba yi-magnetic coercive force (bHc), yintoni amandla angaphakathi okunyanzeliswa (jHc)?
Imagnethi yamagnetic imagnetic field saturation emva kokurhoxiswa kwemagnethi yangaphandle kwimo evaliweyo, imagnetic polarization J kunye nokufakwa kwamagnetic kwangaphakathi B kwaye ayiyi kunyamalala ngenxa yokunyamalala kwe-H kunye nomhlaba wangaphandle wemagnethi, kwaye iya kugcina ixabiso elithile lobungakanani.Eli xabiso libizwa ngokuba yintsalela yemagnethi yokungenisa umazibuthe, ekubhekiswa kuyo njenge-remanence Br, iyunithi ye-SI yi-T, iyunithi ye-CGS yi-Gs (1T=10⁴Gs).Ijika le-demagnetization yemagnethi esisigxina, xa i-reverse magnetic field H inyuka ukuya kwixabiso le-bHc, ukunyanzeliswa kwemagnethi ye-B umazibuthe yayingu-0, ebizwa ngokuba yi-H ixabiso le-reverse magnetic material coercivity magnetic ye-bHc;kwintsimi yamagnetic engasemva H = bHc, ayibonisi amandla emagnethi angaphandle, ukunyanzeliswa kwe-bHc yeempawu zemagnethi ezisisigxina ukuxhathisa i-reverse magnetic field okanye enye i-demagnetization effect.Ukunyanzeliswa kwe-bHc yenye yeeparamitha ezibalulekileyo zoyilo lwesekethe yamagnetic.Xa i-reverse magnetic field H = bHc, nangona umazibuthe engabonakalisi i-magnetic flux, kodwa i-magnetic intensity yemagnethi J ihlala inexabiso elikhulu kwindlela yokuqala.Ke ngoko, iipropathi zemagneti zangaphakathi ze-bHc azonelanga ukubonisa umazibuthe.Xa i-reverse magnetic field H inyuka ukuya kwi-jHc, i-vector micro magnetic dipole magnetic yangaphakathi ngu-0. Ixabiso lemagnethi elibuyela umva libizwa ngokuba yi-intrinsic coercivity ye-jHc.I-Coercivity jHc yiparameter yomzimba ebaluleke kakhulu yemathiriyeli yemagnethi esisigxina, kwaye luphawu lwemathiriyeli yemagnethi esisigxina ukuxhathisa umva wemagnethi yangaphandle okanye enye impembelelo ye-demagnetization, ukugcina isalathiso esibalulekileyo sesakhono saso sokuqala sokuzibuthe.
Yintoni eyona mveliso yamandla iphezulu (BH) m?
Kwigophe le-BH lokukhupha uzibuthe wemathiriyeli kazibuthe esisigxina (kwi-quadrant yesibini), iimagnethi ezahlukeneyo ezihambelanayo zikwiimeko ezahlukeneyo zokusebenza.I-BH demagnetization curve yendawo ethile kwi-Bm kunye ne-Hm (i-horizontal and vertical coordinates) imele ubungakanani bemagnethi kunye ne-induction induction intensity kunye ne-magnetic field of the state.Ikhono le-BM kunye ne-HM yexabiso elipheleleyo lemveliso ye-Bm * Hm egameni lesimo somsebenzi wamagnetic wangaphandle, olingana namandla amagnetic agcinwe kwi-magnet, ebizwa ngokuba yi-BHmax.Imagnethi ekwimo yexabiso eliphezulu (BmHm) imele isakhono semagnethi sangaphandle somsebenzi, esibizwa ngokuba yeyona mveliso yamandla umazibuthe, okanye imveliso yamandla, echazwa njenge (BH) m.Iyunithi ye-BHmax kwinkqubo ye-SI yi-J/m3 (i-joules / m3), kunye nenkqubo ye-CGS ye-MGOe, 1MGOe = 10²/4π kJ/m3.
Yintoni ubushushu beCurie (Tc), yintoni ubushushu bokusebenza kwemagnethi (Tw), ubudlelwane phakathi kwabo?
Iqondo lobushushu leCurie liqondo lobushushu apho imagneti yemathiriyeli yemagnethi ithotywa ukuya ku-zero, kwaye yeyona ndawo ibalulekileyo yoguqulo lwezixhobo zeferromagnetic okanye zeferrimagnetic zibe yipara-magnetic materials.Ubushushu beCurie Tc bunxulumene kuphela nokubunjwa kwezinto kwaye akukho nto inxulumene ne-micro-structure yezinto.Kwiqondo elithile lobushushu, iipropathi zemagneti zezixhobo zemagnethi ezisisigxina zinokuncitshiswa ngoluhlu oluchaziweyo xa kuthelekiswa nobushushu begumbi.Ubushushu bubizwa ngokuba bubushushu obusebenzayo bemagnethi iTw.Ubungakanani bokunciphisa amandla kazibuthe kuxhomekeke kwisicelo umazibuthe, lixabiso elingaqingqwanga, umazibuthe ofanayo osisigxina kwizicelo ezahlukeneyo ezinobushushu obusebenzayo beTw.Ukushisa kweCurie ye-Tc magnetic material imele ithiyori yomda wokushisa osebenzayo wezinto eziphathekayo.Kuyafaneleka ukuba uqaphele ukuba i-Tw esebenzayo yanoma yimuphi umazibuthe osisigxina ayihambelani kuphela ne-Tc, kodwa inxulumene neempawu zemagnethi zemagnethi, ezifana ne-jHc, kunye nemeko yokusebenza yemagnethi kwisekethe yamagnetic.
Yintoni imagnethi yokungena kwimagnethi esisigxina (μrec), yintoni iJ demagnetization curve squareness (Hk / jHc), bathetha ntoni?
Inkcazo yegophe lokukhupha uzibuthe lendawo yokusebenza umazibuthe yeBH D ebuyisela umgca wokutshintsha umva umazibuthe oguquguqukayo, ukuthambeka komgca wokubuyisela ukungeneka μrec.Ngokucacileyo, i-permeability ye-μrec ibonakalisa ukuzinza kwemagnethi phantsi kweemeko zokusebenza eziguqukayo.Isisikweri segophe elisisigxina le-BH demagnetization curve, kwaye yenye yezinto ezibalulekileyo zemagnethi zemagnethi ezisisigxina.Kwiimagnethi ze-sintered Nd-Fe-B, i-μrec = 1.02-1.10, i-μrec encinci kukuba, kungcono ukuzinza kwemagnethi phantsi kweemeko zokusebenza eziguquguqukayo.
Yintoni isekethe yamagnetic, yintoni isekethe yamagnetic evulekileyo, imeko evaliweyo?
Isiphaluka samagnetic sibhekiswa kwintsimi ethile kwi-gap yomoya, edityaniswe ngomnye okanye ubuninzi beemagnethi ezisisigxina, ucingo oluphetheyo lwangoku, isinyithi ngokwemilo ethile kunye nobukhulu.Intsimbi inokuba yintsimbi ecocekileyo, intsimbi ephantsi yekhabhoni, iNi-Fe, i-Ni-Co ialloy enezixhobo eziphezulu zokungena.I-iron ethambileyo, ekwabizwa ngokuba yidyokhwe, idlala ukuqukuqela kolawulo lokuqukuqela, yonyusa umfutho wemagnethi yasekhaya, ithintele okanye inciphise ukuvuza kwamagnetic, kwaye yonyuse amandla omatshini wendima yendima kwisekethe yemagnethi.Ubume bemagnethi umazibuthe omnye udla ngokubizwa ngokuba yindawo evulekileyo xa intsimbi ethambileyo ingekho;xa umazibuthe ukwisekethe yeflux eyenziwe ngentsimbi ethambileyo, umazibuthe ukwimo yesekethe evaliweyo.
Zeziphi iimpawu zomatshini wemagnethi ye-Nd-Fe-B ene-sintered?
Iimpawu zomatshini wemagnethi ye-Nd-Fe-B ene-sintered:
| Ukugoba Amandla /MPa | Amandla oxinzelelo /MPa | Ukuqina /Hv | I-Yong Modulus /kN/mm2 | Ubude/% |
| 250-450 | 1000-1200 | 600-620 | 150-160 | 0 |
Ingabonwa ukuba imagnethi ye-Nd-Fe-B ye-sintered yinto eqhelekileyo ye-brittle.Ngexesha lenkqubo yokwenza, ukudibanisa kunye nokusetyenziswa kwemagnethi, kuyafuneka ukuba uthathele ingqalelo ukuthintela umazibuthe ekubeni uphantsi kwefuthe elibi, ukungqubana, kunye noxinzelelo olugqithisileyo, ukuze kuthintelwe ukuqhekeka okanye ukuwa kwemagnethi.Kuyaphawuleka ukuba amandla magnetic of sintered Nd-Fe-B umazibuthe unamandla kakhulu kwimo magnetic, abantu kufuneka banakekele ukhuseleko lwabo lobuqu ngelixa besebenza, ukuthintela ukunyuka kweminwe ngamandla anamandla okufunxa.
Zeziphi izinto ezichaphazela ukuchaneka kwemagnethi ye-Nd-Fe-B ene-sintered?
Izinto ezichaphazela ukuchaneka kwemagnethi ye-sintered Nd-Fe-B yinkqubo yokucubungula izixhobo, izixhobo kunye neteknoloji yokucubungula, kunye nenqanaba lobugcisa bomqhubi, njl njl. Ukongeza, i-micro-structure yezinto inempembelelo enkulu ukuchaneka komatshini wemagnethi.Umzekelo, umazibuthe onesigaba esingundoqo senkozo erhabaxa, umphezulu othanda ukuba nemingxuma kwimo yomatshini;imagnethi ukukhula okungaqhelekanga okuziinkozo, umgangatho machining state idla ngokuba nomngxuma imbovane;ukuxinana, ukubunjwa kunye nokuqhelaniswa nokulinganisa, ubungakanani be-chamfer buya kungalingani;umazibuthe onomxholo ophezulu weoksijini uyaqhawuka, kwaye uthambekele ekuphumeni i-engile ngexesha lenkqubo yomatshini;Isigaba semagnethi esiphambili seenkozo ezirhabaxa kunye nokuhanjiswa kwesigaba esityebileyo asifani, ukuncamathela okufanayo kunye ne-substrate, ukufana kobunzima bokugquma, kunye nokumelana nomhlwa kwengubo kuya kuba ngaphezulu kwenqanaba eliphambili lokutya okuziinkozo kunye nokuhanjiswa okufanayo kweNd. Umahluko wesigaba esityebileyo somzimba wemagnethi.Ukuze ufumane iimveliso zemagnethi zeNd-Fe-B ezichaneke kakhulu, injineli yokwenza izinto, injineli yomatshini kunye nomsebenzisi kufuneka banxibelelane ngokupheleleyo kwaye basebenzisane omnye nomnye.