Karbid krem\u00edka je jedn\u00fdm z naj\u017eiadanej\u0161\u00edch keramick\u00fdch materi\u00e1lov, ktor\u00fd pon\u00faka vynikaj\u00face vlastnosti, ako je tvrdos\u0165, pevnos\u0165, tepeln\u00e1 odolnos\u0165 a odolnos\u0165 proti kor\u00f3zii\/oxid\u00e1cii.<\/p>\n
Reak\u010dn\u00e9 spekanie je najlep\u0161\u00edm rie\u0161en\u00edm na v\u00fdrobu ve\u013ekej keramiky z karbidu krem\u00edka zlo\u017eit\u00e9ho tvaru vo ve\u013ekom meradle. Nane\u0161\u0165astie je v\u0161ak jeho \u00fa\u010dinnos\u0165 spojen\u00e1 s niektor\u00fdmi nev\u00fdhodami, ako je nerovnomern\u00e9 rozlo\u017eenie hustoty a praskanie spekan\u00fdch v\u00fdrobkov.<\/p>\n
Karbid krem\u00edka (SiC) je jedn\u00fdm z najtvrd\u0161\u00edch keramick\u00fdch materi\u00e1lov, ktor\u00fd pon\u00faka v\u00fdnimo\u010dn\u00fa pevnos\u0165 pri vysok\u00fdch teplot\u00e1ch a je vhodn\u00fd na cel\u00fd rad aplik\u00e1ci\u00ed, ako s\u00fa napr\u00edklad komponenty tesnen\u00ed s tvrd\u00fdm povrchom, \u010dasti zariaden\u00ed na v\u00fdrobu polovodi\u010dov a kon\u0161truk\u010dn\u00e9 komponenty jadrov\u00fdch f\u00faznych reaktorov. Okrem toho sa SiC vyzna\u010duje vynikaj\u00facou odolnos\u0165ou vo\u010di chemik\u00e1li\u00e1m a opotrebovaniu.<\/p>\n
Reak\u010dn\u00e9 a beztlakov\u00e9 spekanie s\u00fa dve z\u00e1kladn\u00e9 met\u00f3dy v\u00fdroby SiC. Reak\u010dn\u00e9 spekanie pon\u00faka ni\u017e\u0161ie teploty spracovania, ale trp\u00ed n\u00edzkou pevnos\u0165ou v ohybe a odolnos\u0165ou vo\u010di chemik\u00e1li\u00e1m, ako s\u00fa siln\u00e9 kyseliny a z\u00e1sady; v porovnan\u00ed s t\u00fdm beztlakov\u00e9 spekanie pon\u00faka lep\u0161iu flexibilitu, vysok\u00fa hustotu spekania a dobr\u00fa tvarov\u00fa schopnos\u0165, ale pri vy\u0161\u0161\u00edch n\u00e1kladoch na spracovanie v d\u00f4sledku pr\u00eddavkov kovov, ako s\u00fa hlin\u00edk, b\u00f3r a uhl\u00edk.<\/p>\n
Spekan\u00fd karbid krem\u00edka vynik\u00e1 medzi svojimi kolegami mimoriadnou tvrdos\u0165ou. S tvrdos\u0165ou pod\u013ea Vickersa 2563 HV - \u010do vysoko prevy\u0161uje po\u017eiadavky na pancier 1500 HV - je spekan\u00fd karbid krem\u00edka tie\u017e mimoriadne h\u00fa\u017eevnat\u00fd materi\u00e1l a vykazuje trhliny medi\u00e1nov\u00e9ho typu, tak\u017ee je vhodn\u00fd na aplik\u00e1cie s viacer\u00fdmi z\u00e1sahmi.<\/p>\n
Spekanie zohr\u00e1va d\u00f4le\u017eit\u00fa \u00falohu pri v\u00fdrobe kvalitn\u00fdch spekan\u00fdch v\u00fdrobkov z karbidu krem\u00edka. Triedy s reak\u010dn\u00fdm sp\u00e1jan\u00edm pon\u00fakaj\u00fa hrub\u00e9 zrno s ni\u017e\u0161ou tvrdos\u0165ou a teplotou pou\u017eitia; triedy s priamym spekan\u00edm pon\u00fakaj\u00fa jemnej\u0161ie \u010dastice pre lep\u0161iu odolnos\u0165 vo\u010di trhlin\u00e1m a teplotu pou\u017eitia, v\u010faka \u010domu s\u00fa lep\u0161ou vo\u013ebou ako triedy s reak\u010dn\u00fdm sp\u00e1jan\u00edm, pokia\u013e ide o tesniace plochy a vysoko v\u00fdkonn\u00e9 tesniace plochy.<\/p>\n
Spekan\u00fd karbid krem\u00edka sa uk\u00e1zal ako odoln\u00fd vo\u010di kor\u00f3zii v kyslom prostred\u00ed v\u010faka svojej vynikaj\u00facej oxida\u010dnej odolnosti, pri\u010dom vytv\u00e1ra okolo svojho materi\u00e1lu kysl\u00edkov\u00fa bari\u00e9ru, ktor\u00e1 ho chr\u00e1ni pred p\u00f4soben\u00edm kysl\u00fdch chemik\u00e1li\u00ed a z\u00e1rove\u0148 zabezpe\u010duje \u010fal\u0161iu chemick\u00fa degrad\u00e1ciu z in\u00fdch agres\u00edvnych prostred\u00ed.<\/p>\n
Odolnos\u0165 karbidu krem\u00edka proti kor\u00f3zii z\u00e1vis\u00ed vo ve\u013ekej miere od faktorov, ako s\u00fa ne\u010distoty, spekanie, f\u00e1zy na hranici z\u0155n, p\u00f3rovitos\u0165 a bezprostredn\u00e1 reak\u010dn\u00e1 hist\u00f3ria jeho materi\u00e1lu. Tak\u00e9to charakteristiky m\u00f4\u017eu zmeni\u0165 jeho dominantn\u00fa reak\u010dn\u00fa postupnos\u0165 v prev\u00e1dzkov\u00fdch podmienkach, a t\u00fdm ovplyvni\u0165 jeho n\u00e1sledn\u00e9 kor\u00f3zne spr\u00e1vanie.<\/p>\n
Beztlakov\u00fd spekan\u00fd karbid krem\u00edka zvy\u010dajne prekon\u00e1va reak\u010dne viazan\u00fd karbid krem\u00edka, pokia\u013e ide o odolnos\u0165 vo\u010di vysok\u00fdm teplot\u00e1m a mechanick\u00fa tvrdos\u0165, ale r\u00f4zne aplik\u00e1cie vy\u017eaduj\u00fa r\u00f4zne vlastnosti materi\u00e1lov; preto v\u00fdber medzi spekan\u00fdm a reak\u010dne viazan\u00fdm z\u00e1vis\u00ed od va\u0161ich konkr\u00e9tnych po\u017eiadaviek.<\/p>\n
Obr\u00e1banie spekan\u00e9ho karbidu krem\u00edka (SSiC) m\u00f4\u017ee by\u0165 n\u00e1ro\u010dn\u00e9 a drah\u00e9 kv\u00f4li jeho extr\u00e9mnej tvrdosti. Spolo\u010dnos\u0165 GAB Neumann pou\u017e\u00edva beztlakov\u00e9 monolitick\u00e9 diely zo spekan\u00e9ho karbidu krem\u00edka vyr\u00e1ban\u00e9 intenz\u00edvnym v\u00fdrobn\u00fdm procesom, ktor\u00fd zah\u0155\u0148a pr\u00edpravu pr\u00e1\u0161ku, mie\u0161anie so spojivom, tvarovanie, izostatick\u00e9 lisovanie za studena a napokon spekanie pri vysok\u00fdch teplot\u00e1ch, a po spekan\u00ed sa nakoniec obr\u00e1baj\u00fa s presn\u00fdmi toleranciami pomocou n\u00e1strojov s diamantov\u00fdm povlakom.<\/p>\n
Karbid krem\u00edka si zachov\u00e1va svoju tvrdos\u0165 a pevnos\u0165 aj pri ve\u013emi vysok\u00fdch teplot\u00e1ch, v\u010faka \u010domu je vysoko odoln\u00fd vo\u010di opotrebovaniu, kor\u00f3zii a tepeln\u00fdm \u0161okom. Okrem toho jeho odolnos\u0165 vo\u010di oxid\u00e1cii patr\u00ed medzi najvy\u0161\u0161ie spomedzi neoxidov\u00fdch keramick\u00fdch materi\u00e1lov a v\u00e1\u017ei o polovicu menej ako oce\u013e.<\/p>\n
Reak\u010dne viazan\u00e9 a priamo spekan\u00e9 v\u00fdrobn\u00e9 procesy na v\u00fdrobu karbidu krem\u00edka s\u00fa dve \u0161iroko vyu\u017e\u00edvan\u00e9 techniky na jeho v\u00fdrobu. Ka\u017ed\u00fd sp\u00f4sob tvarovania zohr\u00e1va neoddelite\u013en\u00fa \u00falohu pri formovan\u00ed kone\u010dnej mikro\u0161trukt\u00fary a vlastnost\u00ed vyr\u00e1ban\u00e9ho keramick\u00e9ho materi\u00e1lu.<\/p>\n
Reak\u010dne viazan\u00fd karbid krem\u00edka sa m\u00f4\u017ee vyr\u00e1ba\u0165 infiltr\u00e1ciou kompaktov zlo\u017een\u00fdch zo zmes\u00ed pr\u00e1\u0161ku a-SiC a uhl\u00edka tekut\u00fdm krem\u00edkom a n\u00e1slednou reakciou tohto nov\u00e9ho SiC s existuj\u00facimi \u010dasticami za vzniku hust\u00fdch zhutnen\u00fdch telies SiC, ktor\u00e9 maj\u00fa \u00fapln\u00fa hustotu.<\/p>\n
Mikro\u0161trukt\u00fara a-SiC s pridru\u017eenou kry\u0161talickou \u0161trukt\u00farou a-SiC -b-SiC poskytuje vynikaj\u00facu odolnos\u0165 proti opotrebovaniu a tepeln\u00fdm \u0161okom, ale elektrick\u00fd odpor je ni\u017e\u0161\u00ed v d\u00f4sledku pr\u00edtomnosti z\u0155n a-SiC aj b-SiC v tejto forme karbidu krem\u00edka.<\/p>\n
Reak\u010dn\u00e9 spekanie je efekt\u00edvna a ekonomick\u00e1 met\u00f3da vytv\u00e1rania extr\u00e9mne h\u00fa\u017eevnatej keramiky z karbidu krem\u00edka s vynikaj\u00facou h\u00fa\u017eevnatos\u0165ou, v\u010faka \u010domu je t\u00e1to met\u00f3da vhodn\u00e1 na pr\u00edpravu ve\u013ek\u00fdch rozmerov alebo komplexn\u00fdch tvarov. N\u00edzke teploty spekania zabezpe\u010duj\u00fa r\u00fdchle \u010dasy spekania, pri\u010dom diely s takmer \u010distou ve\u013ekos\u0165ou sa vytv\u00e1raj\u00fa v priebehu nieko\u013ek\u00fdch min\u00fat; medzi jej jedin\u00e9 nev\u00fdhody patria vysok\u00e9 po\u017eiadavky na materi\u00e1l, n\u00e1klady na spotrebu energie a drah\u00e9 zariadenia.<\/p>\n
Karbid krem\u00edka je jedn\u00fdm z najtvrd\u0161\u00edch a najodolnej\u0161\u00edch keramick\u00fdch materi\u00e1lov na trhu. Svoju tvrdos\u0165 a pevnos\u0165 si zachov\u00e1va aj pri extr\u00e9mne vysok\u00fdch teplot\u00e1ch, \u010do prispieva k jeho v\u00fdnimo\u010dnej odolnosti proti opotrebovaniu. Okrem toho sa t\u00e1to keramika m\u00f4\u017ee pochv\u00e1li\u0165 odolnos\u0165ou vo\u010di tepeln\u00fdm \u0161okom, ako aj odolnos\u0165ou vo\u010di kor\u00f3zii a oxid\u00e1cii; je o polovicu \u0165a\u017e\u0161ia ako oce\u013e, a pritom odol\u00e1va extr\u00e9mnym tlakom a teplotn\u00fdm zmen\u00e1m.<\/p>\n
Tepeln\u00e1 vodivos\u0165 SSiC do zna\u010dnej miery z\u00e1vis\u00ed od zvolen\u00e9ho procesu spekania; beztlakov\u00e9 spekanie alebo spekanie reak\u010dnou v\u00e4zbou vytv\u00e1raj\u00fa r\u00f4zne mikro\u0161trukt\u00fary, ktor\u00e9 ovplyv\u0148uj\u00fa jeho tepelne vodiv\u00e9 vlastnosti.<\/p>\n
Reak\u010dne viazan\u00fd SiC sa vytv\u00e1ra infiltr\u00e1ciou p\u00f3rovit\u00fdch uhl\u00edkov\u00fdch alebo grafitov\u00fdch predliskov tekut\u00fdm krem\u00edkom, ktor\u00fd reaguje s uhl\u00edkom a vytv\u00e1ra stuhnut\u00fa keramiku SiC, ktor\u00e1 sa potom m\u00f4\u017ee lisova\u0165 do tvarov. Reak\u010dne viazan\u00e1 keramika b\u00fdva m\u00e4k\u0161ia a menej hust\u00e1 ako jej n\u00e1protivky z SSiC, ale m\u00e1 dobr\u00fa odolnos\u0165 proti opotrebovaniu pri vy\u0161\u0161\u00edch teplot\u00e1ch a z\u00e1rove\u0148 vysok\u00fa \u00farove\u0148 odolnosti proti oxid\u00e1cii a kor\u00f3zii.<\/p>\n
Oxidy vz\u00e1cnych zem\u00edn sa m\u00f4\u017eu zavies\u0165 ako pr\u00edsady na zlep\u0161enie spekania b-SiC, av\u0161ak ich ve\u013ek\u00fd i\u00f3nov\u00fd polomer im br\u00e1ni prenikn\u00fa\u0165 do kry\u0161t\u00e1lovej mrie\u017eky a uviaznu medzi zrnami - preto je rozhoduj\u00faci v\u00fdber pr\u00edsad, ktor\u00e9 m\u00f4\u017eu prenikn\u00fa\u0165 - hlin\u00edk, b\u00f3r a uhl\u00edk (ABC) je jednou z tak\u00fdchto s\u013eubn\u00fdch pr\u00edsad, ktor\u00e9 sa m\u00f4\u017eu prid\u00e1va\u0165 viazan\u00e9 na zrn\u00e1 pre aplik\u00e1cie spekania pri ni\u017e\u0161\u00edch teplot\u00e1ch spracovania.<\/p>","protected":false},"excerpt":{"rendered":"
Silicon carbide is one of the most desirable ceramic materials, offering outstanding properties such as hardness, strength, heat resistance and corrosion\/oxidation resistance. Reaction sintering is the best solution for producing large, complex shape silicon carbide ceramics at scale. Unfortunately, however, its efficiency comes with some drawbacks such as uneven density distribution and cracking sintered products. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[64],"tags":[],"class_list":["post-104","post","type-post","status-publish","format-standard","hentry","category-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts\/104","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/comments?post=104"}],"version-history":[{"count":1,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts\/104\/revisions"}],"predecessor-version":[{"id":105,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts\/104\/revisions\/105"}],"wp:attachment":[{"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/media?parent=104"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/categories?post=104"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/tags?post=104"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}