{"id":1368,"date":"2024-10-25T08:34:58","date_gmt":"2024-10-25T08:34:58","guid":{"rendered":"https:\/\/nbaem.com\/?p=1368"},"modified":"2024-10-25T08:36:15","modified_gmt":"2024-10-25T08:36:15","slug":"how-to-make-ndfeb-magnet","status":"publish","type":"post","link":"https:\/\/nbaem.com\/sk\/how-to-make-ndfeb-magnet\/","title":{"rendered":"Ako vyrobi\u0165 NdFeB magnet"},"content":{"rendered":"
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NdFeB magnet<\/a> <\/span>st\u00e1le predstavuje najsilnej\u0161\u00ed a naj\u010dastej\u0161ie pou\u017e\u00edvan\u00fd vz\u00e1cne zemn\u00fd permanentn\u00fd magnetick\u00fd materi\u00e1l dnes. Neod\u00fdmov\u00fd magnet sa pod\u013ea v\u00fdrobn\u00e9ho procesu del\u00ed na sinterovan\u00fd neodymov\u00fd magnet, viazan\u00fd neodymov\u00fd magnet a magnetovan\u00fd neodymov\u00fd magnet v extr\u00fazii. Ka\u017ed\u00e1 forma m\u00e1 svoje odli\u0161n\u00e9 magnetick\u00e9 vlastnosti, potom ich spolo\u010dn\u00e9 uplatnenie je men\u0161ie a maj\u00fa vz\u00e1jomn\u00fd doplnkov\u00fd vz\u0165ah. Pou\u017e\u00edvatelia magnetov sa p\u00fdtaj\u00fa, ako sa neodymov\u00e9 magnety vyr\u00e1baj\u00fa. Sinterovan\u00fd neodymov\u00fd magnet sa vyr\u00e1ba tradi\u010dn\u00fdm procesom pr\u00e1\u0161kov\u00e9ho metallurgy a zauj\u00edma absol\u00fatnu prevahu na trhu.<\/span><\/p>\n<\/div>\n<\/div>\n

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Ako sa vyr\u00e1baj\u00fa neodymov\u00e9 magnety?<\/strong><\/p>\n

Sinterovan\u00fd neodymov\u00fd magnet sa pripravuje tak, \u017ee suroviny sa roztavia vo v\u00e1kuu alebo inertnej atmosf\u00e9re v induk\u010dnom tavivom kotli, potom sa spracuj\u00fa v p\u00e1sovej liatine a ochladia sa na vytvorenie Nd-Fe-B zliatinov\u00e9ho pr\u00fa\u017ea. Zliatinov\u00e9 pr\u00fa\u017eky sa drvia na jemn\u00fd pr\u00e1\u0161ok s priemerom nieko\u013eko mikr\u00f3nov. Jemn\u00fd pr\u00e1\u0161ok sa n\u00e1sledne zhutn\u00ed v orienta\u010dnom magnetickom po\u013ea a sinteruje sa do hust\u00fdch telies. Tel\u00e1 sa potom obr\u00e1baj\u00fa do \u0161pecifick\u00fdch tvarov, povrchovo upravuj\u00fa a magnetizuj\u00fa.<\/p>\n

V\u00e1\u017eenie<\/strong><\/p>\n

V\u00e1\u017eenie kvalifikovanej suroviny priamo s\u00favis\u00ed s presnos\u0165ou zlo\u017eenia magnetu. \u010cistota suroviny a stabilita chemick\u00e9ho zlo\u017eenia s\u00fa z\u00e1kladom kvality produktu. Sinterovan\u00fd neodymov\u00fd magnet zvy\u010dajne pou\u017e\u00edva vz\u00e1cny zemn\u00fd zliatinov\u00fd materi\u00e1l ako Pr-Nd Mischmetal, La-Ce Mischmetal a Dy-Fe zliatina z d\u00f4vodu n\u00e1kladov. Vysokov\u00fdhavn\u00fd prvok Bor, Molybden alebo Niob s\u00fa prid\u00e1van\u00e9 ferroalian\u010dn\u00fdm sp\u00f4sobom. Vrstva hrdze, inkl\u00fazie, oxidy a ne\u010distoty na povrchu suroviny je potrebn\u00e9 odstr\u00e1ni\u0165 mikrotryskovacou strojom. Okrem toho by mala ma\u0165 surovina vhodn\u00fa ve\u013ekos\u0165, aby sa zabezpe\u010dila \u00fa\u010dinnos\u0165 v n\u00e1slednom topen\u00ed. Neod\u00fdm m\u00e1 n\u00edzky v\u00fdparn\u00fd tlak a akt\u00edvne chemick\u00e9 vlastnosti, preto pri tavbe doch\u00e1dza k ur\u010ditej miere str\u00e1t v\u00fdparov a oxid\u00e1cie vz\u00e1cnych zemn\u00fdch kovov, a preto treba pri v\u00e1\u017een\u00ed sinterovan\u00e9ho neodymov\u00e9ho magnetu zv\u00e1\u017ei\u0165 pridanie \u010fal\u0161\u00edch vz\u00e1cnych zemn\u00fdch kovov na zabezpe\u010denie presnosti zlo\u017eenia magnetu.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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Tavenie a p\u00e1sov\u00e9 odlievanie<\/strong><\/p>\n<\/div>\n<\/div>\n

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Tavenie a p\u00e1sov\u00e9 odlievanie s\u00fa rozhoduj\u00face pre zlo\u017eenie, kry\u0161talick\u00fd stav a rozlo\u017eenie f\u00e1zy, a t\u00fdm aj pre n\u00e1sledn\u00e9 procesy a magnetick\u00e9 vlastnosti. Suroviny sa zohrievaj\u00fa do roztaven\u00e9ho stavu pomocou stredofrekven\u010dn\u00e9ho a n\u00edzkofrekven\u010dn\u00e9ho induk\u010dn\u00e9ho tavenia za v\u00e1kuu alebo inertnej atmosf\u00e9ry. Odlievanie sa m\u00f4\u017ee spracova\u0165, ke\u010f zliatinov\u00fd roztok dosiahne homogeniz\u00e1ciu, exhaust a odstr\u00e1nenie strusky. Dobr\u00fd mikro\u0161truktur\u00e1lny prie\u0165ah odliatku by mal ma\u0165 dobre rast\u00face a jemnofaktori\u00e1lne \u010dlenov\u00e9 kry\u0161t\u00e1ly, pri\u010dom Nd-bohat\u00e1 f\u00e1za by sa mala rozlo\u017ei\u0165 cez hranice kry\u0161t\u00e1lov. Okrem toho by mal mikro\u0161trukt\u00fara odliatku by\u0165 bez \u03b1-Fe f\u00e1zy. Diagram f\u00e1z Re-Fe ukazuje, \u017ee vz\u00e1cna zemn\u00e1 tern\u00e1rna zliatina nevyhnutne sp\u00f4sob\u00ed vytvorenie \u03b1-Fe f\u00e1zy po\u010das pomal\u00e9ho ochladzovania. Poste\u013ene magnetick\u00e9 vlastnosti f\u00e1zy \u03b1-Fe pri izbovej teplote m\u00f4\u017eu v\u00e1\u017ene po\u0161kodi\u0165 magnetick\u00e9 v\u00fdkony magnetu, a preto ich treba potla\u010di\u0165 r\u00fdchlym ochladzovan\u00edm. Aby sa dosiahol \u017eelan\u00fd efekt r\u00fdchleho ochladenia na potla\u010denie vzniku \u03b1-Fe f\u00e1zy, Showa Denko K. K. vyvinula technol\u00f3giu p\u00e1sov\u00e9ho odlievania a \u010doskoro sa stala rutinnou technol\u00f3giou v odvetv\u00ed. Rovnomern\u00e9 rozlo\u017eenie Nd-bohatej f\u00e1zy a inhibi\u010dn\u00fd \u00fa\u010dinok na \u03b1-Fe f\u00e1zu m\u00f4\u017eu \u00fa\u010dinne zni\u017eova\u0165 celkov\u00fd obsah vz\u00e1cnych zemn\u00fdch kovov, \u010do je priazniv\u00e9 pre v\u00fdrobu vysokov\u00fdkonn\u00fdch magnetov a zni\u017eovanie n\u00e1kladov.<\/p>\n

Hydrog\u00e9nov\u00e1 dekrepit\u00e1cia<\/strong><\/p>\n<\/div>\n<\/div>\n

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Hydrogena\u010dn\u00e9 spr\u00e1vanie vz\u00e1cnych zemn\u00fdch kovov, zliatin alebo medzikovov\u00fdch zl\u00fa\u010den\u00edn a fyzik\u00e1lno-chemick\u00e9 vlastnosti hydridu s\u00fa v\u017edy d\u00f4le\u017eit\u00e9 ot\u00e1zky vo vzorci vz\u00e1cnych zem\u00ed. T\u00e1vovo Nd-Fe-B zliatina sa tie\u017e prejavuje ve\u013emi silnou hypert\u00e9zou. At\u00f3ny vod\u00edka vstupuj\u00fa do medzistavov\u00e9ho priestoru medzi hlavnou f\u00e1zou medzi Kovom a Nd-bohatou fazou a vytv\u00e1raj\u00fa medzistavov\u00fa zl\u00fa\u010deninu. Potom sa zv\u00e4\u010d\u0161\u00ed medzizlo\u017en\u00fd odstup a objem mrie\u017eky sa roz\u0161\u00edri. N\u00e1sledn\u00e9 vn\u00fatorn\u00e9 nap\u00e4tie sp\u00f4sob\u00ed poru\u0161enie zrnen\u00fdch hran\u00edc (medzzrnn\u00e9 praskanie), kry\u0161t\u00e1lov\u00e9 praskanie (transgranul\u00e1rne praskanie) alebo \u0165a\u017en\u00fa prasknutie. Tieto dekrepit\u00e1cie s\u00fa sprev\u00e1dzan\u00e9 praskan\u00edm a b\u00fdvaj\u00fa zn\u00e1me ako hydrog\u00e9nov\u00e1 dekrepit\u00e1cia. Proces hydrog\u00e9novej dekrepit\u00e1cie sinterovan\u00e9ho neodymov\u00e9ho magnetu sa tie\u017e ozna\u010duje ako HD proces. Poru\u0161enie zrnen\u00fdch hran\u00edc a kry\u0161t\u00e1lov\u00e9 praskanie vznikaj\u00face v procese hydrog\u00e9novej dekrepit\u00e1cie NdFeB pr\u00e1\u0161ok na b\u00e1ze kurzu je ve\u013emi krehk\u00fd a v\u00fdhodn\u00fd pre n\u00e1sledn\u00fd proces jetov\u00e9ho mletia. Okrem zv\u00fd\u0161enia efekt\u00edvnosti procesu jetov\u00e9ho mletia je proces hydrog\u00e9novej dekrepit\u00e1cie tie\u017e priazniv\u00fd na \u00fapravu priemernej ve\u013ekosti pr\u00e1\u0161ku.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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Jetov\u00e9 mletie<\/strong><\/p>\n

Jetov\u00e9 mletie sa uk\u00e1zalo ako najpraktickej\u0161ie a naj\u00fa\u010dinnej\u0161ie rie\u0161enie v pr\u00e1\u0161kovom procese. Jetov\u00e9 mletie vyu\u017e\u00edva vysokor\u00fdchlostn\u00fd l\u00fa\u010d inertn\u00e9ho plynu na ur\u00fdchlenie hrub\u00e9ho pr\u00e1\u0161ku na nadzvukov\u00fa r\u00fdchlos\u0165 a zrazanie pr\u00e1\u0161ku navz\u00e1jom. Z\u00e1kladn\u00fdm cie\u013eom pr\u00e1\u0161kov\u00e9ho procesu je n\u00e1js\u0165 vhodn\u00fa priemern\u00fa ve\u013ekos\u0165 \u010dast\u00edc a rozlo\u017eenie ve\u013ekosti \u010dast\u00edc. Rozdiely t\u00fdchto vlastnost\u00ed sa prejavuj\u00fa v makroskopick\u00fdch mierkach, \u010do m\u00e1 priamy vplyv na vypl\u0148ovanie pr\u00e1\u0161kom, orient\u00e1ciu, zhutnenie, demodelov\u00e1nie a mikro\u0161trukt\u00faru vzniknut\u00fa v procese sinterovania, \u010d\u00edm citlivo ovplyv\u0148uje magnetick\u00e9 vlastnosti, mechanick\u00e9 vlastnosti, termoelectrickos\u0165 a chemick\u00fa stabilitu sinterovan\u00e9ho neodymov\u00e9ho magnetu. Ide\u00e1lna mikro\u0161trukt\u00fara je jemn\u00e1 a jednotn\u00e1 hlavn\u00e1 f\u00e1za kry\u0161t\u00e1lu obklopen\u00e1 hladkou a tenkou doplnkovou f\u00e1zou. Navy\u0161e, \u013eahk\u00fd smer magnetiz\u00e1cie hlavnej f\u00e1zy by mal by\u0165 usporiadan\u00fd \u010do najviac v s\u00falade so smerom orient\u00e1cie. Dutiny, ve\u013ek\u00e9 zrnit\u00e9 \u010dastice alebo m\u00e4kk\u00e1 magnetick\u00e1 f\u00e1za poved\u00fa k v\u00fdrazn\u00e9mu zn\u00ed\u017eeniu intrinsic coercivity. Remanencia a \u0161tandardn\u00e1 tvrdos\u0165 krivky demagnetiz\u00e1cie bud\u00fa s\u00fa\u010dasne klesa\u0165, zatia\u013e \u010do \u013eahk\u00fd smer magnetiz\u00e1cie zrna sa odklon\u00ed od smeru orient\u00e1cie. Preto by zliatiny mali by\u0165 podrven\u00e9 na jednorozmerov\u00e9 kry\u0161t\u00e1ly \u010dast\u00edc v rozsahu 3 a\u017e 5 mikr\u00f3nov v priemere.<\/p>\n

Zhut\u0148ovanie<\/strong><\/p>\n<\/div>\n<\/div>\n

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Orientovan\u00e9 zhut\u0148ovanie magnetick\u00fdm po\u013eom spo\u010d\u00edva v vyu\u017eit\u00ed interakcie medzi magnetick\u00fdm pr\u00e1\u0161kom a extern\u00fdm magnetick\u00fdm po\u013eom na usporiadanie pr\u00e1\u0161ku pod\u013ea \u013eahk\u00e9ho smeru magnetiz\u00e1cie a zos\u00faladenie s kone\u010dn\u00fdm smerom magnetiz\u00e1cie. Orientovan\u00e9 zhut\u0148ovanie magnetick\u00fdm po\u013eom je najbe\u017enej\u0161ia cesta na v\u00fdrobu anizotropn\u00e9ho magnetu. Nd-Fe-B zliatina bola v predch\u00e1dzaj\u00facom procese jetov\u00e9ho mletia rozomlet\u00e1 na jednorozmern\u00e9 kry\u0161t\u00e1ly \u010dast\u00edc. Jednokrystalov\u00e9 \u010dastice s\u00fa jednostrannou anizotropiou a ka\u017ed\u00e1 z nich m\u00e1 iba jeden \u013eahk\u00fd smer magnetiz\u00e1cie. Magnetick\u00fd pr\u00e1\u0161ok sa pod vplyvom extern\u00e9ho po\u013ea transformuje zo viacdielneho do jedn\u00e9ho dom\u00e9nov\u00e9ho stavu. magnetick\u00e9 pole po vo\u013enom naplnen\u00ed do formy, potom nastavte smer jednoduch\u00e9ho magnetiz\u00e1cie osi c na s\u00fahlas s smerom vonkaj\u0161ieho magnetick\u00e9ho po\u013ea prostredn\u00edctvom ot\u00e1\u010dania alebo pos\u00favania. Osi c zliatiny pr\u00e1\u0161ku v podstate si zachov\u00e1vaj\u00fa svoj usporiadac\u00ed stav po\u010das procesu zhut\u0148ovania. Zhutnen\u00e9 diely by mali prejs\u0165 demagnetiza\u010dnou lie\u010dbou pred demoldovan\u00edm. Najd\u00f4le\u017eitej\u0161\u00ed ukazovate\u013e procesu zhut\u0148ovania je miera orient\u00e1cie. Miera orient\u00e1cie sinterovan\u00fdch neod\u00fdmov\u00fdch magnetov sa ur\u010duje r\u00f4znymi faktormi, zah\u0155\u0148aj\u00facimi silu orienta\u010dn\u00e9ho magnetick\u00e9ho po\u013ea, ve\u013ekos\u0165 \u010dast\u00edc, zjavn\u00fa hustotu, met\u00f3du zhut\u0148ovania, tlak zhut\u0148ovania a pod.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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Sintria<\/strong><\/p>\n<\/div>\n<\/div>\n

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Hustota zhutnen\u00e9ho dielu m\u00f4\u017ee dosiahnu\u0165 viac ako 95% teoretickej hustoty po spracovanej sinterovacej \u00faprave pri vysokej vakuovej alebo \u010distej inertnej atmosf\u00e9re. Preto sa dutiny v sinterovanom neod\u00fdmovom magnete uzatv\u00e1raj\u00fa, \u010do zabezpe\u010duje rovnomernos\u0165 magnetick\u00e9ho toku a chemick\u00fa stabilitu. Ke\u010f\u017ee trval\u00e9 magnetick\u00e9 vlastnosti sinterovan\u00fdch neod\u00fdmov\u00fdch magnetov s\u00fa \u00fazko spojen\u00e9 so svojou mikro\u0161trukt\u00farou, tie\u017e je kritick\u00e9 tepeln\u00e9 o\u0161etrenie po procese sinterovania pre \u00fapravu magnetick\u00fdch vlastnost\u00ed, najm\u00e4 intrinsic coercivity. F\u00e1zov\u00e9 f\u00e1zy bohat\u00e9 na Nd na hranici zrn sl\u00fa\u017eia ako kvapaln\u00e1 f\u00e1za, ktor\u00e1 m\u00f4\u017ee podpori\u0165 sinterovacie reakcie a opravi\u0165 povrchov\u00e9 defekty na hlavnom zrne. Teplota sinterovania neod\u00fdmov\u00fdch magnetov sa be\u017ene pohybuje od 1050 do 1180 stup\u0148ov Celzia. Pr\u00edli\u0161 vysok\u00e1 teplota povedie k rastu z\u0155n a zn\u00ed\u017eeniu intrinsic coercivity. Aby sa dosiahla ide\u00e1lna intrinsic coercivity, \u0161tvorcov\u00fd priebeh de-magnetiza\u010dn\u00e9ho kriv\u00e9ho a vysokotepeln\u00e9 irreverzn\u00e9 straty, sinterovan\u00fd neod\u00fdmov\u00fd magnet zvy\u010dajne vy\u017eaduje dvojf\u00e1zov\u00e9 temperuj\u00face tepeln\u00e9 o\u0161etrenie na 900 a 500 stup\u0148och Celzia.<\/p>\n

Obr\u00e1banie<\/strong><\/p>\n

Okrem be\u017en\u00e9ho tvaru s miernou ve\u013ekos\u0165ou je sinterovan\u00fd neod\u00fdmov\u00fd magnet \u0165a\u017ek\u00e9 dosiahnu\u0165 po\u017eadovan\u00fd tvar a presnos\u0165 rozmerov na jedenkr\u00e1t z d\u00f4vodu technick\u00fdch obmedzen\u00ed v procese orient\u00e1cie magnetick\u00e9ho po\u013ea zhut\u0148ovania, preto je obr\u00e1banie nevyhnutn\u00fdm procesom pri sinterovanom neod\u00fdmovom magnete. Ako typick\u00fd keramometick\u00fd materi\u00e1l je sinterovan\u00fd neod\u00fdmov\u00fd magnet pomerne tvrd\u00fd a krehk\u00fd, a teda sa prakticky vykon\u00e1vaj\u00fa len rezanie, v\u0155tanie a br\u00fasenie, ktor\u00e9 sa m\u00f4\u017eu aplikova\u0165 na jeho obr\u00e1banie v be\u017enej technol\u00f3gii obr\u00e1bania. bladesk\u00e9 rezanie zvy\u010dajne pou\u017e\u00edvaj\u00fa diamantov\u00e9 alebo CBN potiahnut\u00e9 \u010depele. Dr\u00f4tov\u00e9 rezanie a laserov\u00e9 rezanie s\u00fa vhodn\u00e9 pre obr\u00e1banie magnetov so \u0161peci\u00e1lnymi tvarmi, av\u0161ak s\u00fa spojen\u00e9 s n\u00edzkou v\u00fdrobnou efekt\u00edvnos\u0165ou a vysok\u00fdmi n\u00e1kladmi na spracovanie s\u00fa\u010dasne. V\u0155tanie sinterovan\u00e9ho neod\u00fdmov\u00e9ho magnetu sa prim\u00e1rne vykon\u00e1va diamantom a laserom. Je potrebn\u00e9 zvoli\u0165 trepanie pri vn\u00fatornej dierke prste\u0148a, ak je vn\u00fatorn\u00fd otvor prste\u0148a v\u00e4\u010d\u0161\u00ed ako 4 mm. Ako ved\u013eaj\u0161\u00ed produkt v trepan\u00ed m\u00f4\u017ee by\u0165 trepan\u00fd jadro pou\u017eit\u00fd na v\u00fdrobu in\u00fdch vhodn\u00fdch men\u0161\u00edch magnetov a t\u00fdm v\u00fdznamne zv\u00fd\u0161i\u0165 mieru vyu\u017eitia materi\u00e1lu. Karpov\u00e1 br\u00fa\u0161ka na k\u00f3pijn\u00e9 br\u00fasenie sa vyr\u00e1ba na z\u00e1klade br\u00fasnej plochy.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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Povrchov\u00e1 \u00faprava<\/strong><\/p>\n<\/div>\n<\/div>\n

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Povrchov\u00e1 ochrann\u00e1 \u00faprava je nevyhnutn\u00fd postup pre neod\u00fdmov\u00e9 magnety, najm\u00e4 pre sinterovan\u00e9 neod\u00fdmov\u00e9 magnety. Sinterovan\u00e9 neod\u00fdmov\u00e9 magnety maj\u00fa viacf\u00e1zov\u00fa mikro\u0161trukt\u00faru a pozost\u00e1vaj\u00fa z hlavnej f\u00e1zy Nd2Fe14B, Nd-obsahuj\u00facej f\u00e1zy a B-obsahuj\u00facej f\u00e1zy. Nd-obsahuj\u00faci f\u00e1zov\u00e9 prvky vykazuj\u00fa ve\u013emi siln\u00fa oxid\u00e1ciu a bud\u00fa tvori\u0165 prim\u00e1rny \u010dl\u00e1nok s hlavnou f\u00e1zou za vlhk\u00e9ho prostredia. Mal\u00e9 mno\u017estvo substitu\u010dn\u00fdch prvkov je schopn\u00fdch zlep\u0161i\u0165 chemick\u00fa stabilitu magnetov, ale za cenu magnetick\u00fdch v\u00fdkonov. Preto je ochrana sinterovan\u00e9ho neod\u00fdmov\u00e9ho magnetu prim\u00e1rne zameran\u00e1 na jeho povrch. Povrchov\u00e1 \u00faprava sinterovan\u00e9ho neod\u00fdmov\u00e9ho magnetu sa d\u00e1 rozdeli\u0165 na vlhk\u00fd proces a such\u00fd proces. Vlhk\u00fd proces znamen\u00e1, \u017ee magnety podliehaj\u00fa povrchovej ochrane v \u010distej vode alebo v roztoku. Vlhk\u00fd proces zah\u0155\u0148a fosf\u00e1tovanie, galvanick\u00e9 pokovovanie, elektrol\u00e9zu bez elektr\u00f3dy, elektroforetick\u00e9 pokovovanie, n\u00e1streky rozpra\u0161ovan\u00edm a ponorenie. Such\u00fd proces znamen\u00e1, \u017ee magnety prech\u00e1dzaj\u00fa povrchovou ochrannou \u00fapravou prostredn\u00edctvom fyzik\u00e1lneho alebo chemick\u00e9ho procesu bez kontaktu so roztokom. Such\u00fd proces zvy\u010dajne zah\u0155\u0148a fyzik\u00e1lnu depoz\u00edciu v\u00fdparov (PVD) a chemick\u00fa depoz\u00edciu v\u00fdparov (CVD).<\/p>\n

Magnetiz\u00e1cia<\/strong><\/p>\n<\/div>\n<\/div>\n

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V\u00e4\u010d\u0161ina trvalo magnetick\u00fdch materi\u00e1lov sa pred pou\u017eit\u00edm v zam\u00fd\u0161\u013ean\u00fdch aplik\u00e1ci\u00e1ch nastavuje na magnetiz\u00e1ciu. Proces magnetiz\u00e1cie znamen\u00e1 aplik\u00e1ciu magnetick\u00e9ho po\u013ea pozd\u013a\u017e orienta\u010dn\u00e9ho smeru trval\u00e9ho magnetu a dosiahnutie technickej saturation pri zvy\u0161ovan\u00ed extern\u00e9 magnetick\u00e9 pole. Ka\u017ed\u00fd druh trval\u00e9ho magnetick\u00e9ho materi\u00e1lu potrebuje odli\u0161n\u00fa silu magnetick\u00e9ho po\u013ea na dosiahnutie technickej satur\u00e1cie v smere magnetiz\u00e1cie. Remanencia a intrinsic coercivity bud\u00fa ni\u017e\u0161ie ako ich pr\u00edslu\u0161n\u00e9 hodnoty, pokia\u013e nie je sila vonkaj\u0161ieho magnetick\u00e9ho po\u013ea ni\u017e\u0161ia ako technick\u00e9 satur\u00e1cie magnetiz\u00e1cie. Trval\u00fd magnet mo\u017eno rozdeli\u0165 na isotropick\u00fd typ a anizotropick\u00fd typ pod\u013ea toho, \u010di m\u00e1 \u013eahk\u00fd magnetiza\u010dn\u00fd smer alebo nie. Ako anizotropick\u00fd magnet s vysokou intrinsic coercivity je potrebn\u00e9 magnetizova\u0165 sinterovan\u00fd neod\u00fdmov\u00fd magnet impulzovou magnetiz\u00e1ciou. Kondenz\u00e1tor bude nabit\u00fd po rectifik\u00e1cii, potom elektrick\u00e1 energia v kondenz\u00e1tore okam\u017eite vybije na magnetiza\u010dn\u00e9 zariadenie. Magnetiza\u010dn\u00e9 zariadenie m\u00f4\u017ee generova\u0165 pulzn\u00e9 magnetick\u00e9 pole po\u010das okam\u017eit\u00e9ho prechodu siln\u00e9ho pr\u00fadu cez neho. Preto sa v cieve magnetizuje trval\u00fd magnet. Existuj\u00fa r\u00f4zne vzory magnetiz\u00e1cie, ktor\u00e9 je mo\u017en\u00e9 dosiahnu\u0165 na sinterovanom neod\u00fdmovom magnete, pokia\u013e nekoliduj\u00fa s jeho orienta\u010dn\u00fdm smerom.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"

Neodymium magnet is still the most powerful and frequently used rare earth permanent magnetic material nowadays. Neodymium magnet can be classified to into sintered Neodymium magnet, bonded Neodymium magnet, and hot pressed Neodymium magnet in accordance with the manufacturing process. Each form has their different magnetic properties, then their overlapped […]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_mi_skip_tracking":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1368","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/posts\/1368","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/comments?post=1368"}],"version-history":[{"count":3,"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/posts\/1368\/revisions"}],"predecessor-version":[{"id":1371,"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/posts\/1368\/revisions\/1371"}],"wp:attachment":[{"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/media?parent=1368"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/categories?post=1368"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nbaem.com\/sk\/wp-json\/wp\/v2\/tags?post=1368"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}