Vl\u00e1kno z karbidu krem\u00edka je vysoko v\u00fdkonn\u00fd keramick\u00fd materi\u00e1l s mnoh\u00fdmi v\u00fdhodami, medzi ktor\u00e9 patr\u00ed odolnos\u0165 vo\u010di oxid\u00e1cii pri vysok\u00fdch teplot\u00e1ch, tvrdos\u0165, pevnos\u0165 a n\u00edzka hustota. Okrem toho sa vyzna\u010duje vynikaj\u00facou odolnos\u0165ou vo\u010di kor\u00f3zii a tepelnou stabilitou.<\/p>\n
COVID-19 mal nepriazniv\u00fd vplyv na dopyt a dod\u00e1vate\u013esk\u00e9 re\u0165azce v mnoh\u00fdch odvetviach, \u010do viedlo k spomaleniu v\u00fdroby u v\u00fdrobcov v leteckom a obrannom priemysle.<\/p>\n
Vl\u00e1kna z karbidu krem\u00edka sa vyzna\u010duj\u00fa ako v\u00fdnimo\u010dn\u00e1 vo\u013eba pre kompozity s kovovou a keramickou matricou v\u010faka svojej mimoriadnej odolnosti vo\u010di vysok\u00fdm teplot\u00e1m, ktor\u00fa zabezpe\u010duje ich v\u00fdnimo\u010dn\u00e1 pevnos\u0165 v lome a odolnos\u0165 vo\u010di oxid\u00e1cii, \u010do im umo\u017e\u0148uje zosta\u0165 nepo\u0161koden\u00e9 pri teplot\u00e1ch presahuj\u00facich 1000 F (540 \u00b0F). Ich stabilita spo\u010d\u00edva v n\u00edzkom obsahu kysl\u00edka, ktor\u00fd zais\u0165uje dlhodob\u00fa stabilitu pri vysok\u00fdch teplot\u00e1ch.<\/p>\n
Tento materi\u00e1l predstavuje \u013eahk\u00fa, ale z\u00e1rove\u0148 vysoko v\u00fdkonn\u00fa alternat\u00edvu k superzliatin\u00e1m na b\u00e1ze niklu, pri\u010dom pon\u00faka podobn\u00fa pevnos\u0165, tepeln\u00fa odolnos\u0165 a chemick\u00fa inertnos\u0165, no je z\u00e1rove\u0148 \u013eah\u0161\u00ed a odolnej\u0161\u00ed. Okrem toho v\u010faka svojej chemickej inertnosti odol\u00e1va kor\u00f3zii aj chemick\u00e9mu po\u0161kodeniu.<\/p>\n
Bol vyvinut\u00fd inovat\u00edvny v\u00fdrobn\u00fd proces na v\u00fdrobu vl\u00e1kien z karbidu krem\u00edka odoln\u00fdch vo\u010di vysok\u00fdm teplot\u00e1m. Ako surovina sa pou\u017e\u00edva n\u00edzkomolekul\u00e1rny sil\u00e1n (LPS), ktor\u00fd sa nech\u00e1 reagova\u0165 s organickou zl\u00fa\u010deninou obsahuj\u00facou zhut\u0148ovacie prvky, \u010d\u00edm vznikaj\u00fa polykarbosil\u00e1ny obsahuj\u00face AL a Y (PACS a PYCS). Z nich sa potom pomocou technol\u00f3gie taven\u00e9ho spriadania spriadaj\u00fa nekone\u010dn\u00e9 vl\u00e1kna, ktor\u00e9 sa n\u00e1sledne spekaj\u00fa, \u010d\u00edm vznikaj\u00fa vl\u00e1kna z karbidu krem\u00edka odoln\u00e9 vo\u010di vysok\u00fdm teplot\u00e1m.<\/p>\n
Vl\u00e1kno z karbidu krem\u00edka je pevn\u00fd materi\u00e1l, ktor\u00fd odol\u00e1va extr\u00e9mnym teplot\u00e1m. V\u010faka svojmu stechiometrick\u00e9mu zlo\u017eeniu a polykry\u0161talickej mikrostrukt\u00fare m\u00e1 vysok\u00e9 pevnosti v \u0165ahu, pri\u010dom jeho tvrdos\u0165 a chemick\u00e1 odolnos\u0165 ho predur\u010duj\u00fa na pou\u017eitie pri procesoch kalenia kovov, ako aj pri kalen\u00ed v oleji v r\u00e1mci oper\u00e1ci\u00ed kalenia kovov. Okrem toho karbid krem\u00edka odol\u00e1va prostrediam s vysok\u00fdm tlakom, \u010do z neho rob\u00ed vynikaj\u00facu vo\u013ebu pre tesnenia olejov\u00fdch \u010derpadiel, ako aj pre in\u00e9 mechanick\u00e9 v\u00fdrobky prev\u00e1dzkovan\u00e9 za t\u00fdchto podmienok.<\/p>\n
O\u010dak\u00e1va sa, \u017ee rast\u00faca leteck\u00e1 a vojensk\u00e1 v\u00fdroba, zv\u00fd\u0161en\u00e9 financovanie NASA a \u010fal\u0161ie faktory poved\u00fa k n\u00e1rastu severoamerick\u00e9ho dopytu po vl\u00e1knach z karbidu krem\u00edka, ktor\u00e9 sa pou\u017e\u00edvaj\u00fa v keramick\u00fdch brzdov\u00fdch kot\u00fa\u010doch pre \u0161portov\u00e9 aut\u00e1, ako aj v nepriestreln\u00fdch vest\u00e1ch.<\/p>\n
V\u00fdskumn\u00e9 centrum NASA Glenn vyvinulo mikrovlnn\u00fd proces na v\u00fdrobu SiC vl\u00e1kien s vy\u0161\u0161ou pevnos\u0165ou, ktor\u00fd pom\u00e1ha v\u00fdrobcom zn\u00ed\u017ei\u0165 spotrebu energie, spracovate\u013esk\u00e9 teploty a dobu spracovania, ako aj opravi\u0165 po\u0161koden\u00e9 alebo nekvalitn\u00e9 SiC vl\u00e1kna s cie\u013eom dosiahnu\u0165 lep\u0161\u00ed v\u00fdkon. Okrem toho tento inovat\u00edvny proces \u0161etr\u00ed n\u00e1klady na pracovn\u00fa silu a z\u00e1rove\u0148 zvy\u0161uje v\u00fd\u0165a\u017eok pou\u017eite\u013en\u00e9ho SiC.<\/p>\n
Vl\u00e1kna z karbidu krem\u00edka s\u00fa zn\u00e1me ako mimoriadne pevn\u00e9 a odoln\u00e9 materi\u00e1ly s vynikaj\u00facou tepelnou vodivos\u0165ou a odolnos\u0165ou vo\u010di tepelnej roz\u0165a\u017enosti, ktor\u00e9 s\u00fa odoln\u00e9 vo\u010di kor\u00f3zii, vyzna\u010duj\u00fa sa vysok\u00fdm modulom pru\u017enosti a maj\u00fa n\u00edzku mieru tepelnej roz\u0165a\u017enosti a vynikaj\u00face pevnostn\u00e9 vlastnosti \u2013 v\u010faka t\u00fdmto vlastnostiam s\u00fa vhodn\u00e9 na procesy kalenia v oleji pri tvrden\u00ed kovov, ako aj na pou\u017eitie v materi\u00e1loch odoln\u00fdch vo\u010di oderu alebo v kompozitoch s keramickou matricou.<\/p>\n
Rast trhu s vl\u00e1knami z karbidu krem\u00edka Trh s nekone\u010dn\u00fdmi vl\u00e1knami z karbidu krem\u00edka sa r\u00fdchlo roz\u0161iruje v\u010faka dopytu leteck\u00e9ho a obrann\u00e9ho priemyslu po \u013eahk\u00fdch komponentoch. V\u010faka svojej vynikaj\u00facej odolnosti vo\u010di oxid\u00e1cii a chemickej \u010distote sa nepretr\u017eit\u00e9 vl\u00e1kna z karbidu krem\u00edka vyu\u017e\u00edvaj\u00fa v mnoh\u00fdch aplik\u00e1ci\u00e1ch; zatia\u013e \u010do tkan\u00e9 vl\u00e1kna z karbidu krem\u00edka m\u00f4\u017eu by\u0165 vhodn\u00e9 aj pre vysokoteplotn\u00e9 aplik\u00e1cie, ako s\u00fa jadrov\u00e9 reaktory alebo hutn\u00edcke pece.<\/p>\n
Na sk\u00famanie povrchovej morfol\u00f3gie pripraven\u00fdch vl\u00e1kien SiC-9 a SiC-14 vyroben\u00fdch v na\u0161ej laborat\u00f3riu sme pou\u017eili SEM. Obsah kysl\u00edka v t\u00fdchto vzork\u00e1ch bol iba 0,07 hmotnostn\u00e9ho percenta \u2013 \u010do je v\u00fdrazne menej ako ich stechiometrick\u00fd pomer SiC. Tepeln\u00e1 stabilita bola vynikaj\u00faca, pri\u010dom sa nezistili \u017eiadne zmeny ani po\u010das dlhodob\u00fdch tepeln\u00fdch \u00faprav.<\/p>\n
Vl\u00e1kna z karbidu krem\u00edka s\u00fa pokro\u010dil\u00fdm keramick\u00fdm materi\u00e1lom s vynikaj\u00facimi tepeln\u00fdmi, chemick\u00fdmi a mechanick\u00fdmi vlastnos\u0165ami. V\u010faka svojej odolnosti vo\u010di vysok\u00fdm teplot\u00e1m s\u00fa vhodn\u00e9 pre aplik\u00e1cie, v ktor\u00fdch by sa in\u00e9 materi\u00e1ly r\u00fdchlo po\u0161kodili alebo zlyhali; ich odolnos\u0165 proti te\u010deniu, oxid\u00e1cii a \u00fanave z nich z\u00e1rove\u0148 rob\u00ed vhodn\u00e9 materi\u00e1ly pre pou\u017eitie v leteckom a vojenskom priemysle.<\/p>\n
Odolnos\u0165 SiC vl\u00e1kien vo\u010di kor\u00f3zii vypl\u00fdva z ich n\u00edzkej hustoty p\u00f3rov a ve\u013ekej \u0161pecifickej povrchovej plochy, ktor\u00fdch dosiahnutie je v\u00fdsledkom procesu infiltr\u00e1cie a pyrol\u00fdzy. Polykarbosil\u00e1n z prekurzorov\u00fdch molek\u00fal vstupuje do p\u00f3rov, kde vytv\u00e1ra sekund\u00e1rny karbid krem\u00edka, ktor\u00fd n\u00e1sledne zmen\u0161uje ve\u013ekos\u0165 p\u00f3rov; surov\u00e9 vzorky vyroben\u00e9 v tomto kroku potom prech\u00e1dzaj\u00fa viacer\u00fdmi cyklami infiltr\u00e1cie a pyrol\u00fdzy, \u010d\u00edm sa zvy\u0161uje ich hustota a zni\u017euje por\u00e9znos\u0165.<\/p>\n
Pand\u00e9mia COVID-19 sp\u00f4sobila chaos v dod\u00e1vate\u013esk\u00fdch a odberate\u013esk\u00fdch re\u0165azcoch mnoh\u00fdch odvetv\u00ed. Mnoh\u00e9 tov\u00e1rne museli zastavi\u0165 prev\u00e1dzku, zatia\u013e \u010do leteck\u00e9 spolo\u010dnosti a obrann\u00fd priemysel \u010delia \u0165a\u017ekostiam pri prev\u00e1dzke v d\u00f4sledku obmedzen\u00ed cestovania a n\u00e1kladnej dopravy.<\/p>","protected":false},"excerpt":{"rendered":"
Silicon carbide fiber is a high-performance ceramic material with numerous advantages, including high temperature oxidation resistance, hardness, strength and low […]<\/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-52","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\/52","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=52"}],"version-history":[{"count":1,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/52\/revisions"}],"predecessor-version":[{"id":53,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/posts\/52\/revisions\/53"}],"wp:attachment":[{"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/media?parent=52"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/categories?post=52"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/siliconcarbideceramic.net\/sk\/wp-json\/wp\/v2\/tags?post=52"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}