Karbid krem\u00edka, \u010dastej\u0161ie ozna\u010dovan\u00fd ako karborundum alebo SiC, je tvrd\u00fd keramick\u00fd materi\u00e1l s mnoh\u00fdmi aplik\u00e1ciami. T\u00e1to v\u0161estrann\u00e1 l\u00e1tka sl\u00fa\u017ei ako abraz\u00edvum, m\u00e1 vlastnosti polovodi\u010da so \u0161irok\u00fdm p\u00e1smov\u00fdm rozp\u00e4t\u00edm a m\u00f4\u017ee sa dokonca vyr\u00e1ba\u0165 do kon\u0161truk\u010dn\u00fdch keramick\u00fdch s\u00fa\u010diastok.<\/p>\n
V\u00fdroba zah\u0155\u0148a reakciu a pyrol\u00fdzu polysilox\u00e1nov pod tlakom, rozomletie do formy pr\u00e1\u0161ku, spekanie na vytvorenie pevn\u00fdch tvarov a n\u00e1sledn\u00e9 mletie na kone\u010dn\u00e9 mikro\u0161truktur\u00e1lne tvarovanie. Ka\u017ed\u00fd krok zohr\u00e1va neoddelite\u013en\u00fa \u00falohu pri v\u00fdrobe tohto kone\u010dn\u00e9ho materi\u00e1lu s r\u00f4znymi v\u00fdsledkami v z\u00e1vislosti od pou\u017eit\u00fdch met\u00f3d tvarovania, ktor\u00e9 maj\u00fa v\u00fdznamn\u00fd vplyv na mikro\u0161trukt\u00faru.<\/p>\n
Hust\u00e9 zlo\u017eenie karbidu krem\u00edka zohr\u00e1va k\u013e\u00fa\u010dov\u00fa \u00falohu pri jeho schopnosti odol\u00e1va\u0165 chemick\u00e9mu, tepeln\u00e9mu a mechanick\u00e9mu nam\u00e1haniu. V\u010faka vynikaj\u00facim vlastnostiam tvrdosti a tepelnej vodivosti je karbid krem\u00edka vynikaj\u00facou vo\u013ebou materi\u00e1lu pre vysoko v\u00fdkonn\u00e9 a vysoko nam\u00e1han\u00e9 aplik\u00e1cie.<\/p>\n
Hustej\u0161ie materi\u00e1ly s\u00fa zvy\u010dajne odolnej\u0161ie vo\u010di kor\u00f3zii a opotrebovaniu. Okrem toho ich n\u00edzka miera roz\u0165a\u017enosti\/zmr\u0161\u0165ovania im umo\u017e\u0148uje lep\u0161ie odol\u00e1va\u0165 extr\u00e9mnym teplot\u00e1m, tak\u017ee s\u00fa ide\u00e1lne pre elektrick\u00e9 a plynov\u00e9 syst\u00e9my.<\/p>\n
SiC je tie\u017e ve\u013emi odoln\u00fd vo\u010di \u017eiareniu a m\u00e1 v porovnan\u00ed s in\u00fdmi polovodi\u010dmi nezvy\u010dajne ve\u013ek\u00fa p\u00e1smov\u00fa medzeru, \u010do mu umo\u017e\u0148uje pracova\u0165 pri ove\u013ea vy\u0161\u0161\u00edch teplot\u00e1ch, nap\u00e4tiach a frekvenci\u00e1ch v porovnan\u00ed s in\u00fdmi polovodi\u010dmi. SiC sa preto pou\u017e\u00edva v r\u00f4znych oblastiach elektroniky a priemyslu vr\u00e1tane v\u00fdroby energie, leteck\u00e9ho a automobilov\u00e9ho priemyslu.<\/p>\n
Dosiahnutie vysokej hustoty SiC m\u00f4\u017ee by\u0165 pre ve\u013ek\u00e9 komponenty n\u00e1ro\u010dn\u00e9. V\u010faka technol\u00f3gii rampovej kompresie je v\u0161ak teraz mo\u017en\u00e9 dosiahnu\u0165 rovnomern\u00fa hustotu a\u017e 98% teoretickej hustoty. Proces zah\u0155\u0148a vytvorenie homog\u00e9nnej disperzie pr\u00e1\u0161kovej zmesi submikr\u00f3novej ve\u013ekosti pozost\u00e1vaj\u00facej predov\u0161etk\u00fdm z karbidu krem\u00edka s pr\u00edsadou obsahuj\u00facou b\u00f3r; potom sa t\u00e1to pr\u00e1\u0161kov\u00e1 zmes tvaruje do zelen\u00fdch telies pred spekan\u00edm pri teplote 1900 - 2100 \u00b0C v podmienkach riadenej atmosf\u00e9ry.<\/p>\n
Pr\u00edsady obsahuj\u00face b\u00f3r by sa mali prid\u00e1va\u0165 po\u010das mie\u0161ania pr\u00e1\u0161ku v mno\u017estve zodpovedaj\u00facom jedn\u00e9mu hmotnostn\u00e9mu dielu element\u00e1rneho b\u00f3ru na 100 dielov karbidu krem\u00edka, aby sa dosiahlo bezpe\u010dn\u00e9 zhutnenie bez segreg\u00e1cie na hraniciach z\u0155n.<\/p>\n
Karbid krem\u00edka (C-Si) je umel\u00fd materi\u00e1l zlo\u017een\u00fd z uhl\u00edka (C) a krem\u00edka (Si). M\u00e1 druh\u00fa najtvrd\u0161iu Mohsovu triedu tvrdosti po karbide b\u00f3ru (9) a pon\u00faka v\u00fdnimo\u010dn\u00fa pevnos\u0165, odolnos\u0165 proti opotrebovaniu a kor\u00f3zii; v skuto\u010dnosti dokonca vydr\u017e\u00ed p\u00f4sobenie kysel\u00edn fluorovod\u00edkovej a s\u00edrovej bez toho, aby skorodoval - navy\u0161e voda, v\u00e4\u010d\u0161ina chemik\u00e1li\u00ed vr\u00e1tane l\u00fahov ho nedok\u00e1\u017ee rozpusti\u0165! Karbid krem\u00edka je v\u010faka svojej univerz\u00e1lnosti ako technick\u00fd materi\u00e1l ob\u013e\u00faben\u00fd aj medzi vedcami.<\/p>\n
Vzh\u013eadom na to, \u017ee odol\u00e1va vysokor\u00fdchlostn\u00e9mu rezaniu a br\u00faseniu, ako aj pou\u017eitiu pri abraz\u00edvnom tryskan\u00ed a obr\u00e1ban\u00ed, je \u0161mirge\u013e \u0161iroko vyu\u017e\u00edvan\u00fd pri modern\u00fdch lapid\u00e1rnych pr\u00e1cach v\u010faka svojej trvanlivosti a cenovej v\u00fdhodnosti. Okrem toho sl\u00fa\u017ei ako d\u00f4le\u017eit\u00e1 surovina pri v\u00fdrobe br\u00fasnych a le\u0161tiacich zmes\u00ed.<\/p>\n
Karbid krem\u00edka sa stal hlavn\u00fdm materi\u00e1lom vesm\u00edrnych technol\u00f3gi\u00ed v\u010faka svojej mimoriadnej trvanlivosti a odolnosti vo\u010di \u017eiareniu. Zrkadl\u00e1 vyroben\u00e9 z karbidu krem\u00edka sa preto stali vo\u013ebou pre nieko\u013eko najv\u00e4\u010d\u0161\u00edch teleskopov, ako s\u00fa misie Herschel a BepiColombo, alebo sa z nich dokonca daj\u00fa vyrobi\u0165 pevn\u00e9 r\u00e1my, ktor\u00e9 vydr\u017eia teploty vyskytuj\u00face sa na Venu\u0161i a \u00farove\u0148 \u017eiarenia, ktor\u00e1 prevy\u0161uje o\u010dak\u00e1vania.<\/p>\n
Najnov\u0161ie experiment\u00e1lne d\u00f4kazy ukazuj\u00fa, \u017ee a-SiC je stabiln\u00fd vo f\u00e1ze B1 v \u0161irokom rozsahu podmienok, ktor\u00e9 zodpovedaj\u00fa o\u010dak\u00e1van\u00fdm podmienkam v pl\u00e1\u0161ti exoplan\u00e9t bohat\u00fdch na uhl\u00edk, na rozdiel od jeho spr\u00e1vania na Zemi, kde sa r\u00fdchlo rozklad\u00e1 na oxid kremi\u010dit\u00fd a kysl\u00edk.<\/p>\n
Karbid krem\u00edka, \u010dastej\u0161ie ozna\u010dovan\u00fd ako SiC, je chemick\u00e1 zl\u00fa\u010denina zlo\u017een\u00e1 z krem\u00edka (at\u00f3mov\u00e9 \u010d\u00edslo 14) a uhl\u00edka (at\u00f3mov\u00e9 \u010d\u00edslo 6). M\u00e1 opalizuj\u00faci zelen\u00fd a\u017e modro\u010dierny vzh\u013ead s nehor\u013eav\u00fdmi vlastnos\u0165ami; jeho hustota je 3,21 gramu na kubick\u00fd cm3.<\/p>\n
Karbid krem\u00edka sa v obmedzenom mno\u017estve prirodzene vyskytuje v meteoritoch, lo\u017eisk\u00e1ch korundu a kimberlitu; v\u00e4\u010d\u0161ina karbidu krem\u00edka pou\u017e\u00edvan\u00e9ho v elektronick\u00fdch zariadeniach sa v\u0161ak vyr\u00e1ba synteticky. Edward Acheson prv\u00fdkr\u00e1t synteticky syntetizoval karbid krem\u00edka v roku 1891, ke\u010f sa pok\u00fasil vytvori\u0165 umel\u00e9 diamanty zahrievan\u00edm hliny a pr\u00e1\u0161kov\u00e9ho koksu v elektrickej obl\u00fakovej peci; pri tom si v\u0161imol jasne zelen\u00e9 kry\u0161t\u00e1ly, ktor\u00e9 vyzerali podobne ako diamant pripevnen\u00e9 na uhl\u00edkov\u00fdch elektr\u00f3dach, a nazval tieto kry\u0161t\u00e1ly \"moissanit\" pod\u013ea typu kame\u0148a, ktor\u00fd pripom\u00ednali.<\/p>\n
SiC je polovodi\u010dov\u00fd materi\u00e1l s extr\u00e9mne \u0161irokou p\u00e1smovou medzerou, \u010do mu umo\u017e\u0148uje pracova\u0165 pri vy\u0161\u0161\u00edch teplot\u00e1ch a nap\u00e4tiach ako in\u00e9 polovodi\u010dov\u00e9 materi\u00e1ly. V\u010faka vynikaj\u00facej tepelnej vodivosti doch\u00e1dza k r\u00fdchlemu odvodu tepla, zatia\u013e \u010do jeho hust\u00e1 kry\u0161talick\u00e1 \u0161trukt\u00fara poskytuje vynikaj\u00facu odolnos\u0165 proti opotrebovaniu - ide\u00e1lna pre aplik\u00e1cie, ako s\u00fa rezn\u00e9 n\u00e1stroje.<\/p>\n
Laborat\u00f3ri\u00e1 EAG maj\u00fa rozsiahle sk\u00fasenosti s anal\u00fdzou SiC pomocou objemov\u00fdch aj priestorovo rozl\u00ed\u0161en\u00fdch analytick\u00fdch techn\u00edk. SiC je mimoriadne u\u017eito\u010dn\u00fd materi\u00e1l na v\u00fdrobu polovodi\u010dov, preto\u017ee ho mo\u017eno dopova\u0165 r\u00f4znymi prvkami, aby sa zmenili jeho elektrotermick\u00e9 vlastnosti. Zabezpe\u010denie koncentr\u00e1cie a priestorov\u00e9ho rozlo\u017eenia dopantov pri s\u00fa\u010dasnom odstr\u00e1nen\u00ed ne\u017eiaducich kontaminantov je prvorad\u00e9 pri vytv\u00e1ran\u00ed vysokokvalitn\u00fdch polovodi\u010dov\u00fdch v\u00fdrobkov.<\/p>\n
Karbid krem\u00edka je mimoriadne hust\u00fd materi\u00e1l a jedna z najtvrd\u0161\u00edch dostupn\u00fdch l\u00e1tok, ktor\u00e1 ako keramick\u00fd materi\u00e1l poskytuje vynikaj\u00facu odolnos\u0165 proti kor\u00f3zii, \u010do by mohlo zn\u00ed\u017ei\u0165 akt\u00edvne chladiace syst\u00e9my v elektrick\u00fdch vozidl\u00e1ch.<\/p>\n
Karbid krem\u00edka (SiC) je kovalentne viazan\u00e1 svetlosiv\u00e1 pevn\u00e1 l\u00e1tka s relat\u00edvnou tvrdos\u0165ou diamantu na Mohsovej stupnici. \u017diaruvzdorn\u00e9 materi\u00e1ly s t\u00fdmito vlastnos\u0165ami s\u00fa ide\u00e1lne na pou\u017eitie, preto\u017ee SiC m\u00e1 vysok\u00fa teplotu tavenia, tepeln\u00fa vodivos\u0165 a n\u00edzku tepeln\u00fa roz\u0165a\u017enos\u0165.<\/p>\n
Karbid krem\u00edka m\u00f4\u017ee by\u0165 dopovan\u00fd dus\u00edkom alebo fosforom, \u010d\u00edm vznikne polovodi\u010d typu n, alebo dopovan\u00fd ber\u00fdliom, b\u00f3rom, hlin\u00edkom a g\u00e1liom, \u010d\u00edm vznikne polovodi\u010d typu p. V\u010faka svojmu \u0161irok\u00e9mu p\u00e1smov\u00e9mu rozhraniu dok\u00e1\u017ee spracova\u0165 trikr\u00e1t vy\u0161\u0161ie nap\u00e4tie ako \u0161tandardn\u00e9 krem\u00edkov\u00e9 polovodi\u010de. Karbid krem\u00edka sa stal ob\u013e\u00faben\u00fdm materi\u00e1lom na v\u00fdrobu elektronick\u00fdch zariaden\u00ed v\u010faka svojmu \u0161irok\u00e9mu vyu\u017eitiu ako materi\u00e1l na v\u00fdrobu elektronick\u00fdch s\u00fa\u010diastok.<\/p>\n
Pr\u00edrodn\u00e9 lo\u017eisk\u00e1 SiC sa nach\u00e1dzaj\u00fa v niektor\u00fdch vzork\u00e1ch meteoritov, korundov\u00fdch lo\u017eisk\u00e1ch a kimberlite, ale v\u00e4\u010d\u0161ina priemyseln\u00e9ho SiC sa vyr\u00e1ba synteticky. Varianty SSiC a SiSiC patria v\u010faka svojim tepeln\u00fdm vlastnostiam k naj\u010dastej\u0161ie vyu\u017e\u00edvan\u00fdm materi\u00e1lom pre n\u00e1ro\u010dn\u00e9 podmienky, ako je 3D tla\u010d, v\u00fdroba balistiky, chemick\u00e1 v\u00fdroba a aplik\u00e1cie v energetick\u00fdch technol\u00f3gi\u00e1ch, ako aj komponenty potrubn\u00fdch syst\u00e9mov; ich vy\u0161\u0161ia hustota v porovnan\u00ed s \u010dist\u00fdm kreme\u0148om rob\u00ed z t\u00fdchto zl\u00fa\u010den\u00edn atrakt\u00edvnu n\u00e1hradu kovov a pon\u00fakaj\u00fa dobr\u00fa tuhos\u0165, tvrdos\u0165 a odolnos\u0165 vo\u010di vysok\u00fdm teplot\u00e1m, ktor\u00e9 konkuruj\u00fa tepeln\u00fdm vlastnostiam \u010dist\u00e9ho kreme\u0148a v porovnan\u00ed s \u010dist\u00fdm kreme\u0148om a odolnos\u0165ou vo\u010di vysok\u00fdm teplot\u00e1m, \u010do rob\u00ed z t\u00fdchto zl\u00fa\u010den\u00edn atrakt\u00edvne alternat\u00edvy n\u00e1hrady kovov.<\/p>","protected":false},"excerpt":{"rendered":"
Silicon carbide, more commonly referred to as Carborundum or SiC, is a hard ceramic material with numerous applications. This versatile […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","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":[3],"tags":[],"class_list":["post-90","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\/90","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=90"}],"version-history":[{"count":1,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/90\/revisions"}],"predecessor-version":[{"id":91,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/90\/revisions\/91"}],"wp:attachment":[{"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/media?parent=90"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/categories?post=90"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/tags?post=90"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}