Karbid krem\u00edka (karborundum) je tvrd\u00fd materi\u00e1l - na Mohsovej stupnici tvrdosti miner\u00e1lov je tesne pod diamantom - vyskytuje sa v \u010diernej alebo tmavozelenej kry\u0161t\u00e1lovej forme.<\/p>\n
Extr\u00e9mne tvrd\u00fd br\u00fasny materi\u00e1l pou\u017e\u00edvan\u00fd na br\u00fasenie ne\u017eelezn\u00fdch kovov a keramiky. Vhodn\u00fd aj na br\u00fasenie, opracovanie horn\u00edn a pieskovanie.<\/p>\n
Karbid krem\u00edka (SiC), neredukovate\u013ene tvrd\u00e1 kovalentn\u00e1 zl\u00fa\u010denina zlo\u017een\u00e1 z at\u00f3mov uhl\u00edka a krem\u00edka, sa v rebr\u00ed\u010dku tvrdosti pod\u013ea Mohsovej stupnice rad\u00ed na druh\u00e9 miesto po diamante a kubickom nitride b\u00f3ru.<\/p>\n
Diamantov\u00e9 br\u00fasne kot\u00fa\u010de s\u00fa v\u010faka svojim abraz\u00edvnym vlastnostiam ide\u00e1lne na br\u00fasenie a le\u0161tenie ne\u017eelezn\u00fdch kovov, keramiky a sklenen\u00fdch povrchov. Okrem toho sa diamantov\u00e9 le\u0161tiace kot\u00fa\u010de be\u017ene pou\u017e\u00edvaj\u00fa aj v leteckom a automobilovom priemysle ako met\u00f3da br\u00fasenia metalurgick\u00fdch komponentov.<\/p>\n
\u010cierny SiC je drobiv\u00fd, \u010do umo\u017e\u0148uje jeho viacn\u00e1sobn\u00fa recykl\u00e1ciu v kamenn\u00fdch bubnoch. \u010casom sa jeho zlo\u017eky fragmentuj\u00fa a mikrotrhaj\u00fa, \u010d\u00edm sa vytv\u00e1raj\u00fa nov\u00e9 ostr\u00e9 hrany na zlep\u0161enie br\u00fasnych\/le\u0161tiacich oper\u00e1ci\u00ed.<\/p>\n
SiC vynik\u00e1 medzi tvrd\u00fdmi materi\u00e1lmi svojou extr\u00e9mnou tvrdos\u0165ou, jedine\u010dn\u00fdmi vlastnos\u0165ami a schopnos\u0165ou br\u00fasi\u0165 oce\u013e r\u00fdchlej\u0161ie a \u00fa\u010dinnej\u0161ie ako oxid hlinit\u00fd (Brown Fused Alumina) alebo in\u00e9 pr\u00edrodn\u00e9 br\u00fasiv\u00e1, ako napr\u00edklad B4C. Okrem toho sa SiC m\u00f4\u017ee pochv\u00e1li\u0165 lep\u0161\u00edmi tepeln\u00fdmi vlastnos\u0165ami ako B4C, \u010do z neho rob\u00ed vynikaj\u00facu vo\u013ebu na pou\u017eitie pri vysok\u00fdch teplot\u00e1ch.<\/p>\n
Karbid krem\u00edka (SiC) je h\u00fa\u017eevnat\u00fd, odoln\u00fd keramick\u00fd materi\u00e1l, ktor\u00fd sa \u0161iroko vyu\u017e\u00edva v r\u00f4znych priemyseln\u00fdch odvetviach pre svoju tvrdos\u0165 a \u010fal\u0161ie \u017eiaduce vlastnosti, ako je chemick\u00e1 inertnos\u0165, vysok\u00e1 tepeln\u00e1 vodivos\u0165, n\u00edzky koeficient roz\u0165a\u017enosti, teplotn\u00e1 stabilita a odolnos\u0165 proti kor\u00f3zii a oderu.<\/p>\n
SiC m\u00e1 vynikaj\u00facu mechanick\u00fa pevnos\u0165, vysok\u00fa pevnos\u0165 v \u0165ahu a tlaku a p\u00f4sobiv\u00fa hodnotu Youngovho modulu. Okrem toho je odoln\u00fd vo\u010di kyselin\u00e1m a l\u00fahom a m\u00f4\u017ee sa pochv\u00e1li\u0165 vynikaj\u00facimi vlastnos\u0165ami odolnosti vo\u010di tepeln\u00fdm \u0161okom.<\/p>\n
SiC sa okrem svojej prim\u00e1rnej \u00falohy ako abraz\u00edvneho materi\u00e1lu v br\u00fasnych papieroch a br\u00fasnych kot\u00fa\u010doch \u0161iroko pou\u017e\u00edva na viacer\u00e9 aplik\u00e1cie vr\u00e1tane v\u00fdmuroviek priemyseln\u00fdch pec\u00ed, rezn\u00fdch n\u00e1strojov, s\u00fa\u010diastok odoln\u00fdch proti opotrebovaniu pre \u010derpadl\u00e1 a raketov\u00e9 motory, polovodi\u010dov\u00fdch substr\u00e1tov pre sveteln\u00e9 di\u00f3dy (LED), ako aj polovodi\u010dov\u00fdch substr\u00e1tov pre sveteln\u00e9 di\u00f3dy (LED). Zelen\u00fd SiC sa zvy\u010dajne vyzna\u010duje vy\u0161\u0161ou \u00farov\u0148ou \u010distoty ako \u010dierny SiC na presn\u00e9 br\u00fasenie\/le\u0161tenie, ako aj na polovodi\u010dov\u00e9 substr\u00e1ty; obe odrody pon\u00fakaj\u00fa jedine\u010dn\u00e9 v\u00fdhody v porovnan\u00ed s in\u00fdmi keramick\u00fdmi materi\u00e1lmi, ako je oxid hlinit\u00fd\/zirk\u00f3n, pokia\u013e ide o tvrdos\u0165\/tepeln\u00fa vodivos\u0165\/v\u00fdkonnos\u0165 lomovej h\u00fa\u017eevnatosti, ako aj v pr\u00edpade polovodi\u010dov\u00fdch substr\u00e1tov v porovnan\u00ed s keramick\u00fdmi materi\u00e1lmi, ako je oxid hlinit\u00fd\/zirk\u00f3n, pokia\u013e ide o tvrdos\u0165\/tepeln\u00fa vodivos\u0165\/v\u00fdkonnos\u0165 lomovej h\u00fa\u017eevnatosti v porovnan\u00ed s in\u00fdmi keramick\u00fdmi materi\u00e1lmi, ako je oxid hlinit\u00fd\/zirk\u00f3n, pokia\u013e ide o tvrdos\u0165\/tepeln\u00fa vodivos\u0165\/v\u00fdkonnos\u0165 lomovej h\u00fa\u017eevnatosti v porovnan\u00ed s in\u00fdmi keramikami, ako je Alumina\/Zrconia, ktor\u00fdm sa in\u00e9 keramiky nem\u00f4\u017eu vyrovna\u0165, jej vynikaj\u00face v\u00fdkonnostn\u00e9 charakteristiky, ako je tvrdos\u0165\/tepeln\u00e1 vodivos\u0165\/ lomov\u00e1 h\u00fa\u017eevnatos\u0165\/ lomov\u00e1 h\u00fa\u017eevnatos\u0165, oproti keramik\u00e1m, ako je Alumina\/Zirconia, pokia\u013e ide o tvrdos\u0165\/tepeln\u00fa vodivos\u0165\/ lomov\u00fa h\u00fa\u017eevnatos\u0165\/ lomov\u00fa h\u00fa\u017eevnatos\u0165\/ lomov\u00fa h\u00fa\u017eevnatos\u0165 v\u00fdkonnostn\u00e9 charakteristiky\/ lomov\u00fa h\u00fa\u017eevnatos\u0165\/ lomov\u00fa h\u00fa\u017eevnatos\u0165ness performance characteristics alum \/ zirconia \/ zirconia \/ fractoughness performance \/ fractture toughness \/ fraconia in terms of hardness \/ fractalusive in terms of hardness \/ thermal conductivity \/ fract toughness \/ fractture toughness \/ fractture toughness etc vs etc... ZIN(I\/zirk\u00f3n+ lomov\u00e1 h\u00fa\u017eevnatos\u0165 at\u010f.). vs==f =5=koniak=5. Si=4. ZIN=1<\/p>\n
Karbid krem\u00edka (SiC) je jednou z naj\u013eah\u0161\u00edch, najtvrd\u0161\u00edch a najpevnej\u0161\u00edch modern\u00fdch keram\u00edk na s\u00fa\u010dasnom trhu. Vyzna\u010duje sa vynikaj\u00facou tepelnou vodivos\u0165ou, ako aj vysokou odolnos\u0165ou vo\u010di kyselin\u00e1m a z\u00e1sad\u00e1m, pri\u010dom odol\u00e1va teplot\u00e1m a\u017e 1400 stup\u0148ov C bez toho, aby do\u0161lo k zn\u00ed\u017eeniu pevnosti alebo v\u00fdkonu.<\/p>\n
V\u010faka svojej neuverite\u013enej tvrdosti sa materi\u00e1l kevlar(r) vo ve\u013ekej miere pou\u017e\u00edva na v\u00fdrobu nepriestreln\u00fdch viest. Okrem toho t\u00e1to odoln\u00e1 tkanina pon\u00faka v\u00fdnimo\u010dn\u00e9 vlastnosti odolnosti proti oderu a er\u00f3zii, v\u010faka \u010domu je vynikaj\u00facou vo\u013ebou materi\u00e1lu na v\u00fdrobu d\u00fdz, cykl\u00f3nov a s\u00fa\u010dast\u00ed postrekov.<\/p>\n
Chemick\u00fa odolnos\u0165 SiC mo\u017eno \u010falej zv\u00fd\u0161i\u0165 dopovan\u00edm, napr\u00edklad b\u00f3rom a hlin\u00edkom; po dopovan\u00ed b\u00f3rom sa st\u00e1va polovodi\u010dom typu p; po dopovan\u00ed hlin\u00edkom vznik\u00e1 polovodi\u010d typu n.<\/p>\n
Mechanick\u00e9 vlastnosti karbidu krem\u00edka sa m\u00f4\u017eu v\u00fdrazne zlep\u0161i\u0165, ak sa na\u0148 nanesie atom\u00e1rne tenk\u00fd epitaxn\u00fd povlak graf\u00e9nu. Berkovichove testy vtl\u00e1\u010dania do diamantu odhalili, \u017ee jeho pokrytie graf\u00e9nom m\u00e1 za n\u00e1sledok a\u017e 30% vy\u0161\u0161iu tvrdos\u0165 - pri h\u013abke vtla\u010denia a\u017e 175 nanometrov; predpoklad\u00e1 sa, \u017ee tento jav sa pripisuje tvorbe diam\u00e9nu z tlaku, ktor\u00fd vyv\u00edja indentor po\u010das vtl\u00e1\u010dania.<\/p>\n
Karbid krem\u00edka vynik\u00e1 ako v\u00fdnimo\u010dne tvrd\u00fd a odoln\u00fd materi\u00e1l s ve\u013emi n\u00edzkou tepelnou roz\u0165a\u017enos\u0165ou a vysokou tepelnou vodivos\u0165ou, v\u010faka \u010domu je vhodn\u00fd na aplik\u00e1cie s vysok\u00fdmi teplotn\u00fdmi v\u00fdkyvmi.<\/p>\n
SiC je zn\u00e1my t\u00fdm, \u017ee odol\u00e1va vysok\u00fdm teplot\u00e1m a je odoln\u00fd vo\u010di degrad\u00e1cii chemick\u00fdmi a jadrov\u00fdmi procesmi, pri\u010dom je elektrick\u00fdm polovodi\u010dom s u\u017eito\u010dn\u00fdmi elektrick\u00fdmi vlastnos\u0165ami.<\/p>\n
Edward G. Acheson prv\u00fdkr\u00e1t syntetizoval karborundum v r\u00e1mci svojho pokusu o synt\u00e9zu syntetick\u00fdch diamantov v roku 1891, pri\u010dom pou\u017eil vlastn\u00fd postup na vytvorenie tvrd\u00fdch zelen\u00fdch kry\u0161t\u00e1lov z reakci\u00ed pr\u00e1\u0161kov\u00e9ho krem\u00edka a uhl\u00edka, ktor\u00e9 vytvoril, a nazval svoj v\u00fdtvor karborundum pod\u013ea jeho latinsk\u00e9ho n\u00e1zvu corundum - n\u00e1zov, ktor\u00fd sa d\u00e1va vz\u00e1cnym drah\u00fdm kame\u0148om, ako je korund.<\/p>\n
Reak\u010dne viazan\u00fd karbid krem\u00edka sa vyr\u00e1ba zmie\u0161an\u00edm pr\u00e1\u0161ku SiC s plastifik\u00e1torom a jeho tvarovan\u00edm pred op\u00e4tovnou reakciou s plynn\u00fdm alebo kvapaln\u00fdm krem\u00edkom na v\u00fdrobu \u010fal\u0161ieho SiC. Na druhej strane, priamo spekan\u00fd karbid krem\u00edka sa m\u00f4\u017ee pochv\u00e1li\u0165 jemnej\u0161\u00edmi zrnami s ni\u017e\u0161\u00edmi v\u00fdrobn\u00fdmi n\u00e1kladmi a z\u00e1rove\u0148 vynikaj\u00facou mechanickou pevnos\u0165ou pri izbovej teplote 300 \u00b0C a viac.<\/p>","protected":false},"excerpt":{"rendered":"
Silicon carbide (carborundum) is a hard material – just below diamond on the Mohs scale of mineral hardness – found in black or dark green crystal form. An extremely hard abrasive material used for grinding nonferrous metals and ceramics. Also suitable for sanding, rock tumbling and sandblasting applications. Abrasive Properties Silicon carbide (SiC), an irreducibly […]<\/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-144","post","type-post","status-publish","format-standard","hentry","category-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts\/144","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=144"}],"version-history":[{"count":1,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts\/144\/revisions"}],"predecessor-version":[{"id":145,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/posts\/144\/revisions\/145"}],"wp:attachment":[{"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/media?parent=144"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/categories?post=144"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ceramicatijolart.com\/sk\/wp-json\/wp\/v2\/tags?post=144"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}