{"id":332,"date":"2024-09-30T20:07:51","date_gmt":"2024-09-30T12:07:51","guid":{"rendered":"https:\/\/aluminaceramics.net\/?p=332"},"modified":"2024-10-07T21:19:27","modified_gmt":"2024-10-07T13:19:27","slug":"alumiiniumoksiidkeraamika-moned-omadused-nagu-mikrostruktuur-ja-kristall","status":"publish","type":"post","link":"https:\/\/aluminaceramics.net\/et\/some-characteristics-of-alumina-ceramics-such-as-microstructure-and-crystal\/","title":{"rendered":"Alumiiniumoksiidkeraamika m\u00f5ned omadused, nagu mikrostruktuur ja kristallid."},"content":{"rendered":"

Alumiiniumoksiidkeraamika materjalide omadused s\u00f5ltuvad peamiselt nende keemilistest sidemetest, kristallstruktuurist ja kristallidefektidest. Kristallstruktuuri seisukohast on keraamiliste materjalide aatomitevahelised sidemed peamiselt ioonsidemed, kovalentsed sidemed v\u00f5i ioon-kovalentsed segasidemed. Nendel keemilistel sidemetel on mitte ainult suur sidumisj\u00f5ud, vaid ka suunatus. Kristalldefektid (eriti joondefektid ja dislokatsioonid) v\u00f5ivad kristallis liikuda ning kriitiline nihkepinge, mis on vajalik dislokatsiooni liikumiseks k\u00f5ige tihedamalt joondunud tasapinna ja suuna m\u00f6\u00f6da, on v\u00e4ga v\u00e4ike. Dislokatsioonide ulatuslik liikumine p\u00f5hjustab kristallitasapinnal m\u00e4rgatavat libisemist ja makroplastilist deformatsiooni. Metallide sidemete tugevus ei muutu makroplastilise deformatsiooni eel ja j\u00e4rel oluliselt, kuid keraamikas esinevad ioon- ja kovalentsed sidemed on teistsugused. Keraamika keeruka kristallstruktuuri ja madala s\u00fcmmeetria t\u00f5ttu on dislokatsiooni libisemispinnal liikumisel kristallstruktuuri taastumine raske (positiivsete ja negatiivsete ioonide paigutuse minimaalse energiaseisundi h\u00e4vimise t\u00f5ttu), mis v\u00f5ib viia aatomside h\u00e4vimiseni ja rabedani murdumiseni ilma plastilise deformatsioonita. Erinevate keemiliste sidemete t\u00f5ttu erinevad metalli ja keraamiliste materjalide omadused oluliselt. Keraamika sulamistemperatuur ja k\u00f5vadus v\u00f5ivad olla mitu kuni k\u00fcmme korda k\u00f5rgemad kui sama elementi sisaldavatel metallidel. N\u00e4iteks on Al\u2082O\u2083 sulamistemperatuur umbes kolm korda k\u00f5rgem kui metallilisel alumiiniumil, samas kui k\u00f5vadus on \u00fcle 10 korra k\u00f5rgem kui metallilisel alumiiniumil.<\/p>\n

Alumiiniumoksiidkeraamilise materjali struktuuri teine iseloomulik tunnus on mikrostruktuuri heterogeensus ja keerukus. Metallmaterjalid tahkestuvad tavaliselt \u00fcsna \u00fchtlasest metallisulamist, mille j\u00e4rel saab materjali mikrostruktuuri parandada ja \u00fchtlustada k\u00fclm- ja kuumt\u00f6\u00f6tlemise abil. Metallmaterjalid ei sisalda poore v\u00f5i sisaldavad neid v\u00e4ga v\u00e4he. Keraamilised materjalid aga valmistatakse \u00fcldjuhul pulbri vormimise ja paagutamise teel, mille tulemusena tekib paratamatult teatud hulk poore. Kuigi erineva koostise ja osakeste suurusega pulbreid segatakse kuulveskis, on siiski raske saavutada t\u00e4iesti \u00fchtlast tulemust. Lisaks esineb keraamiliste terade piiridel sageli klaasifaase, mis erinevad maatriksi koostisest ja struktuurist.<\/p>\n

Keraamiliste materjalide struktuurilised omadused m\u00e4\u00e4ravad materjalide omadused, sealhulgas mehaanilised, elektrilised, magnetilised, akustilised, optilised, termilised ja muud omadused. Alumiiniumoksiidkeraamika struktuuriliste omaduste p\u00f5hjal ei ole raske m\u00f5ista, miks struktuurkeraamilistel materjalidel on k\u00f5rge sulamistemperatuur, suur tugevus, kulumiskindlus, korrosioonikindlus ja muud p\u00f5hiomadused, kuid samas on neil ka olulisi puudusi, nagu rabedus, keeruline t\u00f6\u00f6tlemine, madal usaldusv\u00e4\u00e4rsus ja reprodutseeritavus. Need puudused tekitavad struktuurkeraamika inseneritehnilises rakendamises palju raskusi.<\/p>\n

\"alumiiniumoksiidkeraamika\"<\/p>","protected":false},"excerpt":{"rendered":"

The properties of alumina ceramics materials are mainly determined by their chemical bonds, crystal structure and crystal defects. From the […]<\/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":"default","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":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","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":[6],"tags":[],"class_list":["post-332","post","type-post","status-publish","format-standard","hentry","category-alumina-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/posts\/332","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/comments?post=332"}],"version-history":[{"count":3,"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/posts\/332\/revisions"}],"predecessor-version":[{"id":342,"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/posts\/332\/revisions\/342"}],"wp:attachment":[{"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/media?parent=332"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/categories?post=332"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aluminaceramics.net\/et\/wp-json\/wp\/v2\/tags?post=332"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}