Silisyum karb\u00fcr son derece serttir, ancak yine de elmastan daha az serttir. Ancak yine de son derece sert bir malzeme olarak ikinci s\u0131rada yer al\u0131r.<\/p>\n
G\u00f6zenekli karbon ba\u011fl\u0131 elmas preformlar, erime noktas\u0131n\u0131 a\u015fan s\u0131cakl\u0131klarda k\u0131lcal kuvvet yoluyla silikonun inf\u00fcze edilmesiyle infiltrasyona u\u011frar ve bunun \u00fczerine karbon ba\u011flay\u0131c\u0131 grafite d\u00f6n\u00fc\u015f\u00fcr.<\/p>\n
Silisyum karb\u00fcr elmas, elektrik, elektronik ve end\u00fcstri m\u00fchendisli\u011fi alanlar\u0131nda yayg\u0131n olarak kullan\u0131lan, m\u00fckemmel termal iletkenli\u011fe sahip son derece y\u00fcksek s\u0131cakl\u0131kta bir malzemedir. Uygulamalar aras\u0131nda so\u011futma ve \u0131s\u0131tma yar\u0131 iletkenleri, transist\u00f6rler ve g\u00fc\u00e7 LED'lerinin yan\u0131 s\u0131ra LED ekran ayd\u0131nlatma uygulamalar\u0131 yer al\u0131r. SiC\/elmas kompozitler i\u00e7in termal iletkenlik, elmas miktar\u0131 ve boyutu, ba\u011flay\u0131c\u0131 malzemelerinin bile\u015fimi ve bile\u015fenler aras\u0131ndaki aray\u00fczlerinin yap\u0131s\u0131 ve grafitik ara katman\u0131n bu malzemenin termal iletkenli\u011fi \u00fczerindeki etkisi gibi \u00e7e\u015fitli fakt\u00f6rlere ba\u011fl\u0131d\u0131r.<\/p>\n
Son on y\u0131ldan bu yana, m\u00fckemmel termal iletkenli\u011fe sahip a\u015f\u0131nmaya kar\u015f\u0131 y\u00fcksek diren\u00e7li malzemeler olu\u015fturmak, ara\u015ft\u0131rma ve geli\u015ftirmenin devam eden bir hedefi olmu\u015ftur. \u201cSilisyum karb\u00fcr elmas\u201d malzemeler, end\u00fcstriyel uygulamalarda rulman, conta veya astar olarak geleneksel \u00e7elik malzemelerin yerini alabilecek k\u00fcbik b-SiC yap\u0131lar\u0131 olu\u015fturmak i\u00e7in 1425 degC'yi a\u015fan s\u0131cakl\u0131klarda k\u0131lcal kuvvetler yoluyla s\u0131v\u0131 silikonun infiltrasyonu yoluyla \u00fcretilebilir.<\/p>\n
SiC\/elmas kompozitlerinde optimum termal iletkenlik i\u00e7in, termal iletkenli\u011fi art\u0131rmak amac\u0131yla \u00e7e\u015fitli boyut ve fraksiyonlardaki elmas tanelerinin bimodal da\u011f\u0131l\u0131m\u0131 kullan\u0131labilir. Bimodal sistemler, elmas taneleri ile b-SiC matris malzemesinin ana matrisi aras\u0131nda grafitik atomik katmanlara sahip olmalar\u0131 nedeniyle monomodal sistemlere k\u0131yasla \u00f6nemli \u00f6l\u00e7\u00fcde daha fazla termal iletkenlik sunar.<\/p>\n
Ek olarak, grafitik atomik katmanlar aray\u00fcze dik olarak hizalan\u0131r ve termal iletkenli\u011fi art\u0131ran nispeten geni\u015f y\u00fczey alanlar\u0131na sahip bimodal sistemler olu\u015fturur. Elmas daha y\u00fcksek s\u0131cakl\u0131klarda sinterlenirse veya silikon infiltrasyonu s\u0131ras\u0131nda daha k\u0131sa bekletme s\u00fcreleri i\u00e7in tutulursa termal iletkenlik daha da artar - saf b-SiC'nin \u00f6tesine ge\u00e7er! Ayr\u0131ca, malzemelerin termal iletkenli\u011fi serbest silikon ve elmas miktarlar\u0131na da ba\u011fl\u0131d\u0131r.<\/p>\n
Silisyum ve karbon atomlar\u0131ndan olu\u015fan silisyum karb\u00fcr, 9,5'lik ola\u011fan\u00fcst\u00fc bir Mohs sertli\u011fine sahiptir ve b\u00f6ylece sertlik a\u00e7\u0131s\u0131ndan elmastan sonra ikinci s\u0131rada yer al\u0131r. G\u00fcc\u00fc ve dayan\u0131kl\u0131l\u0131\u011f\u0131 nedeniyle silisyum karb\u00fcr \u00e7ok say\u0131da end\u00fcstriyel kullan\u0131m alan\u0131 bulmaktad\u0131r.<\/p>\n
Silisyum karb\u00fcr, d\u00f6rty\u00fczl\u00fc kristal yap\u0131s\u0131 (her elementten d\u00f6rt atom, elmas\u0131n g\u00fc\u00e7l\u00fc d\u00f6rty\u00fczl\u00fc ba\u011flar\u0131na benzer g\u00fc\u00e7l\u00fc kovalent ba\u011flar olu\u015fturmak i\u00e7in bir y\u00fcz merkezli k\u00fcbik kafesi payla\u015f\u0131r), y\u00fcksek gerilme mukavemeti ve d\u00fc\u015f\u00fck s\u00fcrt\u00fcnme katsay\u0131s\u0131 dahil olmak \u00fczere elmasla ayn\u0131 \u00f6zelliklerin \u00e7o\u011funu payla\u015f\u0131r ve her iki malzemeyi de m\u00fckemmel i\u015f par\u00e7as\u0131 malzemeleri haline getirir.<\/p>\n
Silisyum karb\u00fcr \u00e7e\u015fitli teknikler kullan\u0131larak \u00fcretilebilir; sentetik silisyum karb\u00fcr kuvars kumu, petrol kok k\u00f6m\u00fcr\u00fc (veya k\u00f6m\u00fcr kok k\u00f6m\u00fcr\u00fc), odun yongalar\u0131 veya di\u011fer hammaddelerin y\u00fcksek s\u0131cakl\u0131ktaki f\u0131r\u0131nlarda eritilmesi yoluyla \u00fcretilir. Silisyum karb\u00fcr olu\u015fturulduktan sonra sertlik g\u00f6sterir, y\u00fcksek bir erime noktas\u0131na sahiptir ve a\u015f\u0131r\u0131 s\u0131cakl\u0131k ko\u015fullar\u0131 alt\u0131nda bile oksidasyona kar\u015f\u0131 diren\u00e7 g\u00f6sterir.<\/p>\n
Silisyum karb\u00fcr\u00fcn end\u00fcstri i\u00e7in bir\u00e7ok pratik kullan\u0131m\u0131 vard\u0131r. Bu uygulamalardan biri de a\u015f\u0131nd\u0131r\u0131c\u0131lard\u0131r. Ola\u011fan\u00fcst\u00fc diren\u00e7 ve mukavemet \u00f6zellikleri sayesinde silisyum karb\u00fcr, z\u0131mpara ka\u011f\u0131tlar\u0131n\u0131n, ta\u015flama ta\u015flar\u0131n\u0131n ve kesici tak\u0131mlar\u0131n vazge\u00e7ilmez bir par\u00e7as\u0131d\u0131r. Silisyum karb\u00fcr ayr\u0131ca end\u00fcstriyel f\u0131r\u0131nlarda yal\u0131t\u0131m bile\u015feni olarak, pompalarda ve roket motorlar\u0131nda a\u015f\u0131nmaya dayan\u0131kl\u0131 par\u00e7alar ve \u0131\u015f\u0131k yayan diyotlar (LED) i\u00e7in kullan\u0131lan yar\u0131 iletken alt tabakalar olarak da kullan\u0131m alan\u0131 bulmaktad\u0131r.<\/p>\n
Silisyum karb\u00fcr \u00fcretmenin \u00e7e\u015fitli y\u00f6ntemleri vard\u0131r. Geleneksel teknikler, toz halindeki silisyum ve karbonun y\u00fcksek bas\u0131n\u00e7l\u0131 bir eriyikte birle\u015ftirilerek daha sonra istenen \u015fekil ve boyutlarda kesilebilen sinterlenmi\u015f bir silisyum karb\u00fcr blo\u011fu olu\u015fturdu\u011fu bir sinterleme i\u015fleminin kullan\u0131lmas\u0131n\u0131 i\u00e7erir. Di\u011fer bir alternatif ise s\u0131v\u0131 silikonun g\u00f6zenekli grafit ile reaksiyona sokulmas\u0131d\u0131r; bu i\u015flem, ayn\u0131 mekanik \u00f6zelliklerden baz\u0131lar\u0131na sahip olan ancak maliyeti y\u00fcksek olmayan siyah sentetik mozanit olu\u015fturur.<\/p>\n
Aray\u00fczlerinde grafitik ara katmanlar bulunan \u00f6zel olarak \u00fcretilmi\u015f silikon karb\u00fcr ba\u011fl\u0131 elmas malzemelerin, grafitsiz elmas\/SiC aray\u00fczlerini bile a\u015fan ola\u011fan\u00fcst\u00fc y\u00fcksek mukavemetlere sahip oldu\u011fu bulunmu\u015ftur, ancak bunun aray\u00fczey grafitik katmanlardan kaynaklan\u0131p kaynaklanmad\u0131\u011f\u0131 belirsizdir.<\/p>\n
Silisyum karb\u00fcr elmaslar m\u00fckemmel kimyasal stabiliteye sahip son derece esnek malzemelerdir ve bu da onlar\u0131 contalar, astarlar ve nozullar gibi a\u015f\u0131nma uygulamalar\u0131 i\u00e7in uygun hale getirir. Ayr\u0131ca, bu elmaslar harika kesme aletleri olu\u015fturur. G\u00fc\u00e7l\u00fc kristal yap\u0131lar\u0131 ve iyi sertlik \u00f6zellikleri nedeniyle, silisyum karb\u00fcr elmaslar\u0131n i\u015flenmesi di\u011fer bir\u00e7ok sert malzemeye k\u0131yasla nispeten kolayd\u0131r ve ayr\u0131ca d\u00fc\u015f\u00fck s\u00fcrt\u00fcnme katsay\u0131s\u0131na sahiptirler, bu da onu end\u00fcstriyel kullan\u0131mlar i\u00e7in uygun hale getirir.<\/p>\n
Silisyum karb\u00fcr elmaslar, artan a\u015f\u0131nma direnci gereksinimleri nedeniyle h\u0131zl\u0131 bir geli\u015fme g\u00f6stermi\u015ftir. Alt\u0131gen kristal yap\u0131ya sahip karbon ve silikondan olu\u015fan inorganik bir bile\u015fik olan silisyum karb\u00fcr, \u00e7e\u015fitli \u015fekil ve boyutlarda \u00fcretilebilmektedir. Edward Goodrich Acheson ilk silisyum karb\u00fcr bile\u015fi\u011fini 1891'de kil ve toz kok k\u00f6m\u00fcr\u00fcn\u00fc demir bir kapta karborundum olarak bilinen mavi kristaller olu\u015fana kadar \u0131s\u0131tarak yaratt\u0131 - Acheson bu malzemenin metal yap\u0131m\u0131nda kullan\u0131labilece\u011fi i\u00e7in k\u00f6m\u00fcrden daha y\u00fcksek de\u011fere sahip olaca\u011f\u0131na inan\u0131yordu.<\/p>\n
Silisyum karb\u00fcr, y\u00fcksek s\u0131cakl\u0131k ko\u015fullar\u0131nda daha fazla stabiliteye sahip olmas\u0131 ve d\u00fc\u015f\u00fck s\u00fcrt\u00fcnme katsay\u0131s\u0131na sahip olmas\u0131n\u0131n yan\u0131 s\u0131ra \u00f6nemli \u00f6l\u00e7\u00fcde daha ucuz olmas\u0131yla saf elmastan b\u00fcy\u00fck \u00f6l\u00e7\u00fcde farkl\u0131d\u0131r. Bu nedenle, silisyum karb\u00fcr end\u00fcstriyel kullan\u0131mlar i\u00e7in tercih edilen bir malzeme haline gelmi\u015ftir.<\/p>\n
Elmas-siC preformlar i\u00e7in yatak tozu olarak kullan\u0131ld\u0131\u011f\u0131nda, a-Si3N4 yatak tozu silikon karb\u00fcr olu\u015fumunu ve \u015firket katmanlar\u0131n\u0131n olu\u015fumunu \u00f6nler - b\u00f6ylece erimi\u015f silikon i\u00e7ine g\u00f6m\u00fcl\u00fc geleneksel numunelere g\u00f6re elmas-siC aray\u00fcz\u00fcn\u00fcn mukavemetini b\u00fcy\u00fck \u00f6l\u00e7\u00fcde art\u0131r\u0131r.<\/p>\n
Bununla birlikte, bu aray\u00fczlerin kesin do\u011fas\u0131 b\u00fcy\u00fck \u00f6l\u00e7\u00fcde a\u00e7\u0131klanamam\u0131\u015ft\u0131r. Bu durum, grafitik d\u00fczlemler aras\u0131ndaki daha zay\u0131f ba\u011flar\u0131n veya aray\u00fczdeki farkl\u0131 fazlar\u0131n bir sonucu olabilir ve tam olarak anla\u015f\u0131lmas\u0131 i\u00e7in daha fazla ara\u015ft\u0131rma yap\u0131lmas\u0131 gerekmektedir.<\/p>\n
Enerji da\u011f\u0131l\u0131ml\u0131 X-\u0131\u015f\u0131n\u0131 spektrometresi (EDX), 3 C-SiC\/elmas malzemeden yap\u0131lm\u0131\u015f amorf bir tabakadaki atomik yo\u011funluk da\u011f\u0131l\u0131m\u0131n\u0131 de\u011ferlendirmek i\u00e7in kullan\u0131lm\u0131\u015ft\u0131r. Karbon ve silisyum atomlar\u0131 i\u00e7in yo\u011funluk profillerinde, karbonun daha az dik e\u011fim g\u00f6stermesiyle birlikte, ba\u011flanm\u0131\u015f aray\u00fczeylerinin yak\u0131n\u0131nda kademeli bir azalma g\u00f6zlenmi\u015ftir. Silisyum hafif i\u00e7b\u00fckey yo\u011funluk profilleri g\u00f6sterirken karbonunki daha kademeli olmu\u015ftur.<\/p>\n
Elmaslar milyonlarca y\u0131lda olu\u015fan do\u011fal m\u00fccevherlerdir, ancak \u00fcretimleri bir laboratuvarda \u00e7ok daha az paraya sentetik olarak yap\u0131labilir. Benzer \u00f6zelliklere sahip ancak \u00e7ok daha d\u00fc\u015f\u00fck maliyetli bir ba\u015fka sentetik de\u011ferli ta\u015f olan silisyum karb\u00fcr \u00e7ok daha dayan\u0131kl\u0131 ve uygun maliyetlidir. Y\u00fcksek k\u0131r\u0131lma indeksi, \u0131\u015f\u0131\u011f\u0131 di\u011fer de\u011ferli ta\u015flardan daha etkili bir \u015fekilde yans\u0131tmas\u0131n\u0131 sa\u011flarken, dayan\u0131kl\u0131l\u0131\u011f\u0131 onu g\u00fcnl\u00fck kullan\u0131m i\u00e7in uygun hale getirir. Ayr\u0131ca, d\u00fc\u015f\u00fck erime noktas\u0131, bas\u0131n\u00e7 alt\u0131nda \u00e7atlamadan hem y\u00fcksek s\u0131cakl\u0131klara hem de kimyasallara dayanabilece\u011fi anlam\u0131na gelir.<\/p>\n
Elmas-silisyum karb\u00fcr kompozitlerinin mikroyap\u0131s\u0131 tipik olarak SiC ve elmastan olu\u015fan i\u00e7 i\u00e7e ge\u00e7mi\u015f \u00fc\u00e7 boyutlu a\u011flardan olu\u015fur. Par\u00e7ac\u0131k boyutu ve morfolojisi, \u00fc\u00e7l\u00fc ba\u011flant\u0131 silisyum karb\u00fcrlerin nihai yap\u0131s\u0131n\u0131 belirler; tipik olarak grafitik aray\u00fcz atom katmanlar\u0131, elmas\/SiC y\u00fczeyiyle s\u0131k\u0131 ba\u011flar olu\u015fturmak i\u00e7in y\u00fczeye dik olarak y\u00f6nelir - kal\u0131nl\u0131klar\u0131 tipik olarak silisyum karb\u00fcr atomlar\u0131 ile elmas atom katmanlar\u0131 aras\u0131ndaki ba\u011f uzunlu\u011fundan \u00e7ok daha azd\u0131r.<\/p>\n
Silisyum karb\u00fcr elmas\u0131n optimum termal iletkenli\u011fi i\u00e7in atomlar\u0131n\u0131n nas\u0131l etkile\u015fime girdi\u011fini anlamak \u00e7ok \u00f6nemlidir. Elmas-silisyum karb\u00fcr aray\u00fczlerini ve bunlar\u0131n yap\u0131sal parametrelerini ve etkile\u015fimlerini incelemek i\u00e7in bir senkrotron X-\u0131\u015f\u0131n\u0131 \u0131\u015f\u0131n\u0131 kullan\u0131labilir. Sonu\u00e7lar par\u00e7ac\u0131klar aras\u0131 etkile\u015fimlerin zay\u0131f oldu\u011funu g\u00f6stermi\u015ftir; elmas ve SiC par\u00e7ac\u0131klar\u0131 aras\u0131ndaki temas alanlar\u0131 cams\u0131 karbon katmanlar\u0131, grafitik s\u0131n\u0131r katmanlar\u0131 ve mikro g\u00f6zenekler i\u00e7erir - bu da elmas\u0131n zay\u0131f termal iletkenli\u011finin bir g\u00f6stergesidir.<\/p>\n
SiC ve elmas yak\u0131n etkile\u015fim i\u00e7indedir, ancak mukavemeti ayn\u0131 zamanda mikro yap\u0131s\u0131na da ba\u011fl\u0131d\u0131r. Bu mikro yap\u0131, y\u00fczey alan\u0131 boyunca yaln\u0131zca minimum grafitik ara katman kaplamas\u0131yla \u00fc\u00e7 boyutlu bir elmas ve silisyum karb\u00fcr par\u00e7ac\u0131klar\u0131 a\u011f\u0131ndan olu\u015fur; ayr\u0131ca bu mikro yap\u0131, k\u0131r\u0131lma direnci gibi mekanik \u00f6zellikleri de belirler.<\/p>\n
Paralel aray\u00fczlerin molek\u00fcler dinamik sim\u00fclasyonlar\u0131nda g\u00f6sterildi\u011fi gibi, daha fazla elmas\/SiC aray\u00fcz\u00fc y\u00fckl\u00fc ucuna do\u011fru e\u011fildik\u00e7e bir konsol numunesinin g\u00fcc\u00fc artar. 40 nanometre e\u011fime sahip bir numunenin \u00f6zellikle g\u00fc\u00e7l\u00fc oldu\u011fu kan\u0131tlanm\u0131\u015ft\u0131r.<\/p>","protected":false},"excerpt":{"rendered":"
Silicon carbide is extremely hard, yet still less so than diamond. But it still ranks second as an extremely hard material. Porous carbon-bonded diamond preforms undergo infiltration by infusing silicon through capillary force at temperatures exceeding its melting point, whereupon the carbon binder transforms into graphite. Thermal Conductivity Silicon carbide diamond is an extremely high-temperature […]<\/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-409","post","type-post","status-publish","format-standard","hentry","category-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/posts\/409","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/comments?post=409"}],"version-history":[{"count":1,"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/posts\/409\/revisions"}],"predecessor-version":[{"id":410,"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/posts\/409\/revisions\/410"}],"wp:attachment":[{"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/media?parent=409"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/categories?post=409"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ceramicatijolart.com\/tr\/wp-json\/wp\/v2\/tags?post=409"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}