Karburidi i silicit i sinteruar pa presion konsiderohet si karburidi i silicit i sinteruar m\u00eb premtues, dhe forma komplekse dhe madh\u00ebsi t\u00eb m\u00ebdha t\u00eb qeramikave t\u00eb karburidit t\u00eb silicit mund t\u00eb p\u00ebrgatiten me procesin e sinterimit pa presion. N\u00eb var\u00ebsi t\u00eb mekanizmit t\u00eb sinterimit, ky lloj karburidi silici i sinteruar mund t\u00eb ndahet m\u00eb tej n\u00eb sinterim n\u00eb faz\u00eb t\u00eb ngurt\u00eb dhe sinterim n\u00eb faz\u00eb t\u00eb l\u00ebng\u00ebt. \u03b2-SiC q\u00eb p\u00ebrmban sasi t\u00eb vogla gjurm\u00ebsh SiO mund t\u00eb sinterizohet n\u00eb presion atmosferik duke shtuar B dhe C. Kjo metod\u00eb p\u00ebrmir\u00ebson ndjesh\u00ebm kinetik\u00ebn e sinterizimit t\u00eb karbhidit t\u00eb silicit. I dopuar me nj\u00eb sasi t\u00eb p\u00ebrshtatshme B, B gjendet n\u00eb kufijt\u00eb e grimcave t\u00eb SiC gjat\u00eb sinterizimit dhe formon pjes\u00ebrisht nj\u00eb zgjidhje t\u00eb ngurt\u00eb me SiC, duke ulur k\u00ebshtu energjin\u00eb e kufirit t\u00eb grimcave t\u00eb SiC. Dopimi me nj\u00eb sasi t\u00eb moderuar t\u00eb karbonit t\u00eb lir\u00eb \u00ebsht\u00eb i dobish\u00ebm p\u00ebr sinterimin n\u00eb faz\u00eb t\u00eb ngurt\u00eb sepse sip\u00ebrfaqja e SiC zakonisht oksidohet me formimin e nj\u00eb sasie t\u00eb vog\u00ebl SiO, dhe shtimi i nj\u00eb sasie t\u00eb moderuar t\u00eb C ndihmon q\u00eb filmi i SiO n\u00eb sip\u00ebrfaqen e SiC t\u00eb reduktohet dhe hiqet, duke rritur k\u00ebshtu energjin\u00eb e sip\u00ebrfaqes. Megjithat\u00eb, sinterimi n\u00eb faz\u00eb t\u00eb l\u00ebng\u00ebt do t\u00eb ket\u00eb nj\u00eb efekt negativ, sepse C do t\u00eb reagoj\u00eb me shtesat oksiduese p\u00ebr t\u00eb gjeneruar gaz, duke formuar nj\u00eb num\u00ebr t\u00eb madh hapjesh n\u00eb trupin qeramik t\u00eb sinteruar, gj\u00eb q\u00eb ndikon n\u00eb procesin e dend\u00ebsimit. Past\u00ebrtia, imt\u00ebsia dhe p\u00ebrb\u00ebrja fazore e l\u00ebnd\u00ebs s\u00eb par\u00eb jan\u00eb shum\u00eb t\u00eb r\u00ebnd\u00ebsishme n\u00eb procesin e sinterimit t\u00eb karbhidit t\u00eb silikonit. S. Proehazka sinteroi karbhid silikoni me dend\u00ebsi m\u00eb t\u00eb lart\u00eb se 98% n\u00eb 2020\u00b0C n\u00ebn presion atmosferik duke shtuar sasi t\u00eb p\u00ebrshtatshme t\u00eb B dhe C nj\u00ebkoh\u00ebsisht n\u00eb pluhurat ultrafine \u03b2-SiC (q\u00eb p\u00ebrmbajn\u00eb m\u00eb pak se 2% oksigjen). Megjithat\u00eb, sistemi SiC-B-C i p\u00ebrket kategoris\u00eb s\u00eb sinterimit n\u00eb faz\u00eb t\u00eb ngurt\u00eb, i cili k\u00ebrkon nj\u00eb temperatur\u00eb t\u00eb lart\u00eb sinterimi, dhe ka rezistenc\u00eb t\u00eb ul\u00ebt ndaj thyerjes, me modalitet thyerjeje tipik p\u00ebrmes kristalit, kokrra t\u00eb trasha dhe nj\u00ebtrajtshm\u00ebri t\u00eb dob\u00ebt. Fokusi i k\u00ebrkimeve t\u00eb huaja mbi SiC \u00ebsht\u00eb kryesisht i p\u00ebrqendruar n\u00eb sinterimin n\u00eb faz\u00eb t\u00eb l\u00ebng\u00ebt, dometh\u00ebn\u00eb, me nj\u00eb num\u00ebr t\u00eb caktuar shtesash p\u00ebr sinterim, n\u00eb nj\u00eb temperatur\u00eb m\u00eb t\u00eb ul\u00ebt p\u00ebr t\u00eb arritur dend\u00ebsimin e SiC. Sinterimi n\u00eb faz\u00eb t\u00eb l\u00ebng\u00ebt i SiC jo vet\u00ebm q\u00eb ul temperatur\u00ebn e sinterimit krahasuar me sinterimin n\u00eb faz\u00eb t\u00eb ngurt\u00eb, por gjithashtu p\u00ebrmir\u00ebson mikrostruktur\u00ebn, dhe k\u00ebshtu pronat e trupit t\u00eb sinteruar p\u00ebrmir\u00ebsohen krahasuar me ato t\u00eb trupit t\u00eb sinteruar n\u00eb faz\u00eb t\u00eb ngurt\u00eb.
\nM. Omori et al. p\u00ebrdor\u00ebn oksidet e tokave t\u00eb rralla t\u00eb p\u00ebrziera me AlO ose boride p\u00ebr t\u00eb sinteruar dend\u00ebsisht SiC. Suzuki, nga ana tjet\u00ebr, sinteroi SiC vet\u00ebm me AlO si shtes\u00eb n\u00eb rreth 2000 \u00b0C. A. Mulla et al. sinteruan \u03b2-SiC me madh\u00ebsi 0.5 \u03bcm (me nj\u00eb sasi t\u00eb vog\u00ebl SiO n\u00eb sip\u00ebrfaqen e grimcave) me AlO dhe YO si shtesa n\u00eb 1850\u20131950 \u00b0C, dhe arrit\u00ebn nj\u00eb dend\u00ebsi relative t\u00eb qeramik\u00ebs SiC m\u00eb t\u00eb madhe se 95.1% t\u00eb dend\u00ebsis\u00eb teorike, dhe grimcat ishin t\u00eb im\u00ebta, me madh\u00ebsi mesatare 1.5 \u03bcm.
\nMikro-struktura e qeramik\u00ebs s\u00eb karbidit t\u00eb silikonit u gjet se kishte grimca t\u00eb m\u00ebdha dhe nj\u00eb struktur\u00eb n\u00eb form\u00eb shkopi me rezistenc\u00eb t\u00eb mir\u00eb ndaj thyerjes. Grimcat n\u00eb form\u00eb shkopi rrisin rezistenc\u00ebn ndaj thyerjes, nd\u00ebrsa ulin fort\u00ebsin\u00eb e qeramik\u00ebs s\u00eb karbidit t\u00eb silikonit. P\u00ebr t\u00eb arritur fort\u00ebsi dhe rezistenc\u00eb m\u00eb t\u00eb mir\u00eb ndaj thyerjes, duke ulur temperatur\u00ebn e sinterimit, jan\u00eb b\u00ebr\u00eb shum\u00eb p\u00ebrpjekje p\u00ebr t\u00eb p\u00ebrmir\u00ebsuar pronat e k\u00ebtij karbidi silikoni t\u00eb sinteruar, duke rregulluar p\u00ebrb\u00ebrjen e faz\u00ebs xhami me shtesa t\u00eb ndryshme. Gjat\u00eb procesit t\u00eb sinterimit, futja e faz\u00ebs s\u00eb l\u00ebngshme n\u00eb kufirin e kokrr\u00ebs dhe struktura unike nd\u00ebrfaq\u00ebsore \u00e7uan n\u00eb dob\u00ebsimin e struktur\u00ebs nd\u00ebrfaq\u00ebsore dhe thyerja e materialit u ndryshua n\u00eb nj\u00eb modalitet t\u00eb plot\u00eb thyerjeje p\u00ebrgjat\u00eb kristalit, gj\u00eb q\u00eb rezultoi n\u00eb nj\u00eb rritje t\u00eb konsiderueshme t\u00eb fort\u00ebsis\u00eb dhe q\u00ebndrueshm\u00ebris\u00eb s\u00eb materialit. Megjithat\u00eb, duke marr\u00eb parasysh se p\u00ebrdorimi i shtes\u00ebs AlO gjeneron nj\u00eb faz\u00eb xhami me pik\u00eb t\u00eb ul\u00ebt t\u00eb shkrirjes dhe avullueshm\u00ebri t\u00eb lart\u00eb, e cila do t\u00eb p\u00ebsoj\u00eb avullim t\u00eb fort\u00eb n\u00eb temperatura m\u00eb t\u00eb larta, duke shkaktuar humbje peshe t\u00eb materialit dhe duke ndikuar negativisht n\u00eb dend\u00ebsimin e materialit, fraksioni masiv i AlO n\u00eb shtes\u00eb duhet t\u00eb rritet n\u00eb m\u00ebnyr\u00eb t\u00eb p\u00ebrshtatshme.<\/p>","protected":false},"excerpt":{"rendered":"
Pressureless sintered silicon carbide is considered to be the most promising sintered silicon carbide, and complex shapes and large sizes of silicon carbide ceramics can be prepared by the pressureless sintering process. Depending on the sintering mechanism, this kind of sintered silicon carbide can be further divided into solid-phase sintering and liquid-phase sintering. \u03b2-SiC containing […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[30],"tags":[],"class_list":["post-578","post","type-post","status-publish","format-standard","hentry","category-sic-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/posts\/578","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/comments?post=578"}],"version-history":[{"count":1,"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/posts\/578\/revisions"}],"predecessor-version":[{"id":579,"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/posts\/578\/revisions\/579"}],"wp:attachment":[{"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/media?parent=578"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/categories?post=578"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/siliconcarbide.net\/sq\/wp-json\/wp\/v2\/tags?post=578"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}