R\u00e4nikarbiid (SiC) on \u00e4\u00e4rmiselt k\u00f5va r\u00e4ni ja s\u00fcsiniku s\u00fcnteetiline \u00fchend, mis esineb looduslikult moissanitina ja v\u00e4hemal m\u00e4\u00e4ral ka s\u00fcsinikdioksiidi sisaldavates meteoriitides.<\/p>\n
Kvartsi, mida toodetakse r\u00e4niliiva ja koksi sulatamisel k\u00f5rgel temperatuuril elektriahjus, on v\u00e4hemalt 70 erinevat kristallvormi; k\u00f5ige levinum on vurttsiidi sarnase heksagonaalse kristallstruktuuriga alfavorm.<\/p>\n
R\u00e4nikarbiid, mida \u00fcldisemalt nimetatakse karborundiks, on erakordse k\u00f5vaduse ja keemilise vastupidavuse omadustega mitteoks\u00fcdeeriv keraamiline \u00fchend, mis on teemandi j\u00e4rel teisel kohal. Lisaks sellele peab r\u00e4nikarbiid puhtal kujul vastu oks\u00fcdeerumisele k\u00f5rgematel temperatuuridel, mis tagab usaldusv\u00e4\u00e4rsema elektrijuhtivuse ja elektrijuhtivuse.<\/p>\n
Kuumutage r\u00e4niliiva koos s\u00fcsinikuga elektriahjus, et toota SiC. Saadud rohelisest kuni sinakasmustani ulatuvat kristallilist materjali saab seej\u00e4rel eraldada erinevate f\u00fc\u00fcsikaliste omadustega klassidesse: n\u00e4iteks metallurgilise klassi A kristallid on j\u00e4medate kihtidega, samas kui klassi b kristallid moodustavad siledamad struktuurid.<\/p>\n
Need mitmekihilised kihilised struktuurid on eriliste elektriliste, optiliste ja soojuslike omadustega. Nende aatomisidemed koosnevad neljast r\u00e4ni aatomist, mis on seotud nelja s\u00fcsinikuaatomiga korrap\u00e4ratult ruudukujuliselt, moodustades neli kuusnurkset kristalli; see tagab laia ribal\u00f5hega pooljuhtide omadused. Ekstrusiooni v\u00f5i k\u00fclma isostaatilise pressimisega saab neid materjale vormida vardadeks v\u00f5i torudeks, mida saab kasutada varrastena ja torudena.<\/p>\n
R\u00e4nikarbiid (SiC), mida \u00fcldisemalt nimetatakse karborundiks, on r\u00e4ni ja s\u00fcsiniku sitke keemiline \u00fchend, millel on laia ribal\u00f5hega pooljuhtide omadused. SiC on oma olemuselt tulekindel ja tuntud ka oma k\u00f5rge soojusjuhtivuse ja madala soojuspaisumise omaduste poolest, mis muudavad selle v\u00e4ga vastupidavaks soojus\u0161okkide suhtes.<\/p>\n
Kristalliline SiC kristalliseerub tihedalt pakitud struktuuris, kus neli r\u00e4ni ja neli s\u00fcsiniku aatomit on seotud tetraeedrilise koordinatsiooniga, ja sellel on \u00fcle 70 pol\u00fct\u00fc\u00fcbi; alfa-SiC esineb k\u00f5ige sagedamini temperatuuril \u00fcle 2000 kraadi, mille kristallstruktuur on heksagonaalne, sarnane Wurttsiidile. Vahepeal esineb madalamatel temperatuuridel beetamoodustus, mille tsinkblendeline kristallstruktuur sarnaneb teemandile ja sfaleriidi moodustumine.<\/p>\n
Karborund on looduses \u00e4\u00e4rmiselt haruldane aine, kuid kosmoses leiduvas s\u00fcsinikusisaldusega meteoriidis on see p\u00f5hielement. Esmakordselt s\u00fcnteesiti seda materjali kunstlikult 1891. aastal Edward Achesoni poolt osana tema t\u00f6\u00f6st kunstlike teemantide valmistamisel, kuid l\u00f5puks avastati see materjal looduslikult 1893. aastal Arizona Canyon Diablo meteoriidist ja nimetati Moissanite'iks Nobeli preemia laureaadi Henri Moissani j\u00e4rgi.<\/p>\n
R\u00e4nikarbiidil on \u00e4\u00e4rmiselt k\u00f5va pind, mille Mohsi skaala hinnang Mohsi skaalal on 9, mis teeb sellest k\u00f5ige k\u00f5vema mittekoksiidkeraamika ja \u00fche k\u00f5ige k\u00f5vema materjali \u00fcldiselt. See on suurep\u00e4rane materjalivalik mehaanilise kulumisega seotud rakenduste jaoks, n\u00e4iteks abrasiivide ja tulekindlate materjalide jaoks, samas on tal head soojusomadused, mis taluvad nii k\u00f5rgeid temperatuure kui ka termilisi \u0161okke.<\/p>\n
R\u00e4ni asendab poole s\u00fcsinikuaatomitest, mis tagab paremad soojusjuhtimisomadused t\u00e4nu r\u00e4ni ja s\u00fcsiniku sarnasele aatomiraadiusele - see aitab v\u00e4hendada footonide hajumist.<\/p>\n
R\u00e4nikarbiid esineb kollastest rohelistest kuni sinakasmustani helendavate kristallidena, mis lagunemisel 2700 kraadi juures sublimeeruvad. Kuigi r\u00e4nikarbiid on vees lahustumatu, lahustub ta sulatatud leelistes, nagu NaOH ja KOH, ning sulatatud rauas ning tema Youngi moodul ja k\u00f5vadus s\u00f5ltuvad tekstuurist, virnastamisvigadest, terade suurusest ja terapiiride iseloomust.<\/p>\n
R\u00e4nikarbiidi lai sagedusvahe v\u00f5imaldab taluda r\u00e4nist k\u00f5rgemat temperatuuri ja pinget, mist\u00f5ttu see sobib rakendusteks, mis n\u00f5uavad kiireid ja samas usaldusv\u00e4\u00e4rseid elektroonikaseadmeid. Lisaks sellele on selle v\u00f5ime taluda sellist pinget hindamatu v\u00e4\u00e4rtusega elektris\u00f5idukite akus\u00fcsteemides, mis v\u00e4hendavad nii suurust kui ka kaalu, j\u00e4ttes t\u00e4ielikult v\u00e4lja inverterid.<\/p>\n
SiC on populaarne materjal t\u00e4nu oma keraamiliste ja pooljuhtide omaduste kombinatsioonile, mis aitab kaasa elektroonikatehnoloogia arengule. Lisaks sellele on tema k\u00f5vadus, tugevus, madal soojuspaisumine ja keemilise reaktsiooni vastupidavus aidanud kaasa selle populaarsuse t\u00f5usule.<\/p>\n
R\u00e4nikarbiidi toodetakse puhta r\u00e4niliiva ja s\u00fcsiniku kuumutamisel elektriahjus, mille k\u00e4igus saadakse nii metallurgilisi kui ka abrasiivseid valuplokke, mida tuntakse vastavalt kvaliteedile ja kasutusotstarbele a-SiC ja b-SiC nime all. P\u00e4rast valuplokkide vormimist l\u00f5igatakse need vastavalt soovitud rakendustele eri suurusteks ja kujuga, enne kui need segatakse soovitud omaduste saavutamiseks t\u00e4iendavate elementidega, n\u00e4iteks alumiiniumi v\u00f5i l\u00e4mmastikuga.<\/p>","protected":false},"excerpt":{"rendered":"
Silicon Carbide (SiC) is an extremely hard synthetic compound of silicon and carbon that occurs naturally as the gem moissanite […]<\/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-62","post","type-post","status-publish","format-standard","hentry","category-sic-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/posts\/62","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/comments?post=62"}],"version-history":[{"count":1,"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/posts\/62\/revisions"}],"predecessor-version":[{"id":63,"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/posts\/62\/revisions\/63"}],"wp:attachment":[{"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/media?parent=62"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/categories?post=62"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/et\/wp-json\/wp\/v2\/tags?post=62"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}