{"id":50,"date":"2024-03-28T09:10:32","date_gmt":"2024-03-28T01:10:32","guid":{"rendered":"http:\/\/siliconcarbideceramic.net\/?p=50"},"modified":"2024-07-07T21:43:15","modified_gmt":"2024-07-07T13:43:15","slug":"vlastnosti-karbidu-kremika","status":"publish","type":"post","link":"https:\/\/siliconcarbideceramic.net\/sk\/silicon-carbide-properties\/","title":{"rendered":"Vlastnosti karbidu krem\u00edka"},"content":{"rendered":"

Karbid krem\u00edka (SiC) je mimoriadne odoln\u00fd materi\u00e1l s extr\u00e9mne tvrdou tvrdos\u0165ou pod\u013ea Mohsovej stupnice 9 a estetick\u00fdm vzh\u013eadom, ktor\u00fd sa vyrovn\u00e1 diamantu.<\/p>\n

Laborat\u00f3ri\u00e1 EAG maj\u00fa rozsiahle sk\u00fasenosti s anal\u00fdzou SiC na tieto vlastnosti pomocou objemov\u00fdch a priestorovo rozl\u00ed\u0161en\u00fdch analytick\u00fdch techn\u00edk. M\u00f4\u017ee sl\u00fa\u017ei\u0165 ako elektrick\u00fd izolant aj ako polovodi\u010d.<\/p>\n

Tvrdos\u0165<\/h2>\n

Karbid krem\u00edka je jednou z najtvrd\u0161\u00edch l\u00e1tok na svete, na Mohsovej stupnici je na deviatom mieste a z h\u013eadiska tvrdosti je druh\u00fd za diamantom. Karbid b\u00f3ru a diamant s\u00fa e\u0161te tvrd\u0161ie ako karbid krem\u00edka - medzi jeho \u010fal\u0161ie pou\u017eitia patria rezn\u00e9 n\u00e1stroje, nepriestreln\u00e9 vesty, automobilov\u00e9 s\u00fa\u010diastky a zrkadl\u00e1 pre astronomick\u00e9 teleskopy. Tvrd\u00fd a pevn\u00fd povrch karbidu krem\u00edka je skvel\u00fd na pou\u017eitie ako rezn\u00e9 br\u00fasivo a rezn\u00e9 n\u00e1stroje, kon\u0161truk\u010dn\u00e9 materi\u00e1ly (nepriestreln\u00e9 vesty), automobilov\u00e9 s\u00fa\u010diastky a zrkadl\u00e1 pou\u017e\u00edvan\u00e9 \u010falekoh\u013eadmi!<\/p>\n

Keramika odoln\u00e1 vo\u010di tepeln\u00fdm \u0161okom je extr\u00e9mne tvrd\u00e1 neoxidov\u00e1 keramika. V\u010faka svojej pevnosti, vysokej tepelnej vodivosti, n\u00edzkej tepelnej roz\u0165a\u017enosti a vynikaj\u00facej odolnosti proti oxid\u00e1cii je nenahradite\u013en\u00fdm \u017eiaruvzdorn\u00fdm materi\u00e1lom.<\/p>\n

Karbid krem\u00edka (at\u00f3mov\u00e9 \u010d\u00edslo 14) a uhl\u00edk (at\u00f3mov\u00e9 \u010d\u00edslo 6) tvoria anorganick\u00fa zl\u00fa\u010deninu zn\u00e1mu ako karbid krem\u00edka s dvoma prim\u00e1rnymi koordina\u010dn\u00fdmi tetra\u00e9drami tvoren\u00fdmi kovalentne viazan\u00fdmi \u0161tyrmi at\u00f3mami uhl\u00edka a \u0161tyrmi at\u00f3mami krem\u00edka, ktor\u00e9 s\u00fa kovalentne spojen\u00e9, \u010d\u00edm vytv\u00e1raj\u00fa v\u00fdnimo\u010dne pevn\u00fa a tuh\u00fa tesne ulo\u017een\u00fa \u0161trukt\u00faru s vynikaj\u00facou pevnos\u0165ou a tuhos\u0165ou; jej polytypy sa dokonca m\u00f4\u017eu uklada\u0165 na seba a vytv\u00e1ra\u0165 polytypy. Karbid krem\u00edka poskytuje vlastnosti polovodi\u010da so \u0161irokou p\u00e1smovou medzerou, ktor\u00fd vy\u017eaduje trikr\u00e1t menej energie na uvo\u013enenie elektr\u00f3nov z orbit\u00e1lnych stavov v porovnan\u00ed s krem\u00edkom.<\/p>\n

Odolnos\u0165 proti kor\u00f3zii<\/h2>\n

Najd\u00f4le\u017eitej\u0161ou vlastnos\u0165ou karbidu krem\u00edka je jeho odolnos\u0165 vo\u010di kor\u00f3zii. Nielen\u017ee je odoln\u00fd vo\u010di najagres\u00edvnej\u0161\u00edm kyselin\u00e1m (chlorovod\u00edkovej, s\u00edrovej a fluorovod\u00edkovej), z\u00e1sad\u00e1m a rozp\u00fa\u0161\u0165adl\u00e1m, ak\u00e9 si len mo\u017eno predstavi\u0165, ako aj vo\u010di oxida\u010dn\u00fdm m\u00e9di\u00e1m, ako je kyselina dusi\u010dn\u00e1 alebo vodn\u00e1 para, ale dokonca sa m\u00f4\u017ee pochv\u00e1li\u0165 vynikaj\u00facimi izola\u010dn\u00fdmi vlastnos\u0165ami proti po\u0161kodeniu extr\u00e9mnymi teplotami alebo elektrick\u00fdmi po\u013eami.<\/p>\n

Spekan\u00fd karbid krem\u00edka pon\u00faka vynikaj\u00facu tepeln\u00fa odolnos\u0165 v\u010faka svojej hustote, tvrdosti, vlastnostiam polovodi\u010da so \u0161irok\u00fdm p\u00e1smom, ktor\u00e9 umo\u017e\u0148uj\u00fa ni\u017e\u0161iu spotrebu energie elektr\u00f3nov na posun vodivostn\u00e9ho p\u00e1sma, a n\u00edzkemu koeficientu tepelnej roz\u0165a\u017enosti.<\/p>\n

Odolnos\u0165 proti kor\u00f3zii mo\u017eno zv\u00fd\u0161i\u0165 aj pr\u00edtomnos\u0165ou spekan\u00fdch pr\u00edsad, f\u00e1z na hranici zrna a p\u00f3rovitosti; ich typ a mno\u017estvo z\u00e1vis\u00ed od toho, ako r\u00fdchlo kor\u00f3zia reaguje s in\u00fdmi prostrediami.<\/p>\n

Oxida\u010dn\u00e9 stavy karbidu krem\u00edka mo\u017eno kontrolova\u0165 prostredn\u00edctvom p\u00f4sobenia uhl\u00edka ako pasiva\u010dn\u00e9ho \u010dinidla, \u010do pom\u00e1ha zni\u017eova\u0165 mieru kor\u00f3zie a predl\u017eova\u0165 \u017eivotnos\u0165 v\u00fdrobkov vystaven\u00fdch oxida\u010dn\u00fdm prostrediam v prev\u00e1dzke.<\/p>\n

Tepeln\u00e1 vodivos\u0165<\/h2>\n

Karbid krem\u00edka je mimoriadne tvrd\u00fd materi\u00e1l, ktor\u00fd sa nach\u00e1dza niekde medzi oxidom hlinit\u00fdm (9 na Mohsovej stupnici) a diamantom (10). V\u010faka kombin\u00e1cii tvrdosti a tepelnej stability je karbid krem\u00edka vynikaj\u00facou vo\u013ebou materi\u00e1lu pre n\u00e1ro\u010dn\u00e9 mechanick\u00e9 aplik\u00e1cie v s\u00fa\u010diastkach ur\u010den\u00fdch na odol\u00e1vanie opotrebovaniu, ako aj v \u017eiaruvzdorn\u00fdch materi\u00e1loch.<\/p>\n

V\u010faka svojej vynikaj\u00facej odolnosti vo\u010di tepeln\u00fdm \u0161okom a n\u00edzkej tepelnej roz\u0165a\u017enosti je silik\u00f3nov\u00e1 guma vhodn\u00e1 aj na pou\u017eitie v prostred\u00ed s vysok\u00fdmi teplotami a na komponenty pou\u017e\u00edvan\u00e9 v potrubn\u00fdch syst\u00e9moch.<\/p>\n

Karbid krem\u00edka mo\u017eno dopova\u0165 r\u00f4znymi prvkami, aby sa zmenili jeho elektronick\u00e9 vlastnosti. Dopovanie dus\u00edkom alebo fosforom ho zmen\u00ed na polovodi\u010d typu n, zatia\u013e \u010do dopovanie ber\u00fdliom, b\u00f3rom alebo hlin\u00edkom ho zmen\u00ed na polovodi\u010d typu p.<\/p>\n

Rozdiel medzi valen\u010dn\u00fdm a vodivostn\u00fdm p\u00e1smom karbidu krem\u00edka s\u0165a\u017euje prep\u00ednanie elektr\u00f3nov medzi t\u00fdmito dvoma p\u00e1smami, \u010do mu umo\u017e\u0148uje vydr\u017ea\u0165 a\u017e 10-kr\u00e1t viac elektrick\u00fdch pol\u00ed, ne\u017e sa stane krehk\u00fdm a rozpadne sa, ako to dok\u00e1\u017ee silik\u00f3n.<\/p>\n

Elektrick\u00e1 vodivos\u0165<\/h2>\n

Karbid krem\u00edka pon\u00faka cel\u00fd rad elektrick\u00fdch vlastnost\u00ed, ktor\u00e9 sa daj\u00fa prisp\u00f4sobi\u0165 dopovan\u00edm. Dopovanie zah\u0155\u0148a prid\u00e1vanie pr\u00edmes\u00ed do jeho kry\u0161t\u00e1lovej \u0161trukt\u00fary s cie\u013eom vytvori\u0165 vo\u013en\u00e9 elektr\u00f3ny a diery, ktor\u00e9 ved\u00fa elektrick\u00fd pr\u00fad, \u010d\u00edm sa dosiahnu hodnoty vodivosti SiC desa\u0165kr\u00e1t vy\u0161\u0161ie ako u krem\u00edka.<\/p>\n

Elektrick\u00e9 vlastnosti karbidu krem\u00edka s\u00fa do ve\u013ekej miery dan\u00e9 jeho p\u00e1smovou medzerou. Tento rozdiel medzi energetick\u00fdmi hladinami valen\u010dn\u00e9ho a vodivostn\u00e9ho p\u00e1sma at\u00f3mu ur\u010duje, ak\u00e9 ve\u013ek\u00e9 elektrick\u00e9 pole m\u00f4\u017ee vydr\u017ea\u0165; karbid krem\u00edka sa m\u00f4\u017ee pochv\u00e1li\u0165 \u0161ir\u0161ou p\u00e1smovou medzerou ako jeho krem\u00edkov\u00fd n\u00e1protivok, \u010do mu umo\u017e\u0148uje zn\u00e1\u0161a\u0165 takmer dvakr\u00e1t v\u00e4\u010d\u0161ie nap\u00e4tie.<\/p>\n

V\u010faka vysok\u00e9mu nap\u00e4\u0165ov\u00e9mu odporu je neod\u00fdm ide\u00e1lny na pou\u017eitie v nap\u00e1jac\u00edch zariadeniach elektrick\u00fdch vozidiel, ktor\u00e9 zabezpe\u010duj\u00fa dlh\u0161iu dojazdov\u00fa vzdialenos\u0165 a vy\u0161\u0161iu \u00fa\u010dinnos\u0165 riadenia bat\u00e9rie. Okrem toho jeho ni\u017e\u0161ia hmotnos\u0165 v porovnan\u00ed s alternat\u00edvami, ako je napr\u00edklad nitrid g\u00e1lia, umo\u017e\u0148uje v\u00fdrobcom v\u00fdkonovej elektroniky v\u00fdrazne zn\u00ed\u017ei\u0165 rozmery a hmotnos\u0165 a z\u00e1rove\u0148 odol\u00e1va\u0165 vysok\u00fdm teplot\u00e1m s minim\u00e1lnym koeficientom tepelnej roz\u0165a\u017enosti.<\/p>\n

\"Vlastnosti<\/p>","protected":false},"excerpt":{"rendered":"

Silicon Carbide (SiC) is an extremely durable material with an extremely hard Mohs scale hardness rating of 9 and an […]<\/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":"default","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":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","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":[3],"tags":[],"class_list":["post-50","post","type-post","status-publish","format-standard","hentry","category-sic-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/50","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/comments?post=50"}],"version-history":[{"count":3,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/50\/revisions"}],"predecessor-version":[{"id":188,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/50\/revisions\/188"}],"wp:attachment":[{"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/media?parent=50"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/categories?post=50"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/tags?post=50"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}