Nitr\u00ed\u00f0bundi\u00f0 k\u00edsilkarb\u00ed\u00f0 f\u00e6r ekki s\u00f6mu athygli og vi\u00f0brag\u00f0sbundi\u00f0 e\u00f0a brennt k\u00edsilkarb\u00ed\u00f0. \u00dea\u00f0 er \u00ed lagi. \u00dea\u00f0 er uppteki\u00f0 af \u00fev\u00ed a\u00f0 sty\u00f0ja ofnvagna, kl\u00e6\u00f0a \u00e1lfrumur og \u00feola slitskemmdir sem ox\u00ed\u00f0bundnar m\u00farsteinar \u00feola ekki. \u00c9g hef eytt n\u00e6gum t\u00edma me\u00f0 NSiC \u2014 einnig skrifa\u00f0 NBSiC e\u00f0a nitride-bonded SiC \u2014 til a\u00f0 segja \u00feetta sk\u00fdrt: \u00feetta er ekki \u201c\u00f3d\u00fdr \u00fatg\u00e1fa\u201d af \u00fe\u00e9ttum SiC. \u00deetta er anna\u00f0 efni me\u00f0 annan tilgang.<\/p>\n
Uppskriftin er einf\u00f6ld \u00e1 bla\u00f0i. \u00de\u00fa tekur k\u00edsilkarb\u00ed\u00f0korn, b\u00e6tir vi\u00f0 k\u00edsilm\u00e1lmi, m\u00f3tar formi\u00f0 og brennir \u00ed nitri. K\u00edsillinn umbreytist \u00ed k\u00edsiln\u00edtr\u00ed\u00f0 og \u00fea\u00f0 n\u00edtr\u00ed\u00f0 ver\u00f0ur bindiefni sem heldur k\u00edsilkarb\u00ed\u00f0kornunum saman. Venjuleg hlutf\u00f6ll eru um 70\u201380% SiC og 20\u201330% Si\u2083N\u2084. Samdr\u00e1ttur vi\u00f0 n\u00edtreringu er l\u00edtill, sem gerir \u00fea\u00f0 kleift a\u00f0 b\u00faa til st\u00f3rar pl\u00f6tur, m\u00farsteina og fl\u00f3kin form \u00e1n afl\u00f6gunarvandam\u00e1la sem einkenna \u00f6nnur keramik.<\/p>\n
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\u00de\u00e9ttleiki er venjulega \u00e1 bilinu 2,6\u20132,8 g\/cm\u00b3. Opin porleiki \u00ed sta\u00f0alflokkum er oft um 12\u201317%. \u00deessi porleiki er \u00fea\u00f0 fyrsta sem f\u00f3lk misskilur. \u00deetta er ekki galli \u00ed e\u00f0li s\u00ednu. \u00deetta er \u00e1st\u00e6\u00f0an fyrir \u00fev\u00ed a\u00f0 efni\u00f0 \u00feolir varmaskokk sem myndi sprengja full\u00fe\u00e9ttan l\u00edkama, og \u00e1st\u00e6\u00f0an fyrir \u00fev\u00ed a\u00f0 \u00fea\u00f0 er l\u00e9ttara en bindu-SiC \u00ed k\u00edlnvagni. Sumar n\u00fat\u00edma ger\u00f0ir eru aftur brenndar e\u00f0a form\u00faluger\u00f0ar til a\u00f0 loka yfirbor\u00f0sholr\u00fdmum me\u00f0 k\u00edsilskel. \u00de\u00e6r haga s\u00e9r frekar eins og \u00fe\u00e9ttur hita\u00feolandi efni en svampur.<\/p>\n
Styrkurinn er l\u00e6gri en \u00ed \u00fe\u00e9ttum SiSiC. Brotmod\u00fall vi\u00f0 stofuhita \u00ed venjulegum ofns- og hita\u00feolnum flokkum getur veri\u00f0 \u00ed tugum MPa, ekki 250 MPa sagan sem \u00fe\u00fa heyrir um bindireaksj\u00f3narbundnar geisla. Hinn gagnlegi hluti er hva\u00f0 gerist vi\u00f0 hitastig. Nitr\u00ed\u00f0bundi\u00f0 k\u00edsilkarb\u00ed\u00f0 heldur bur\u00f0argetu vel fyrir ofan \u00feann punkt \u00fear sem frj\u00e1ls k\u00edsill \u00ed vi\u00f0brag\u00f0sbundnu SiC byrjar a\u00f0 m\u00fdkjast. Hagn\u00fdt \u00fej\u00f3nustuhiti er oft gefinn upp \u00e1 bilinu 1450\u20131600 \u00b0C, allt eftir andr\u00famslofti, \u00e1lagi og hvort um er a\u00f0 r\u00e6\u00f0a f\u00ednan, steyp\u00f0an kjarna e\u00f0a gr\u00f3fari pressa\u00f0an m\u00farstein. \u00de\u00fa munt samt beygja pl\u00f6tu ef \u00fe\u00fa treystir marka\u00f0st\u00f6lum \u00e1n \u00feess a\u00f0 kanna \u00e1lags\u00feol.<\/p>\n
Hitaeinkennileiki er g\u00f3\u00f0ur mi\u00f0a\u00f0 vi\u00f0 kordier\u00edt e\u00f0a mull\u00edt, venjulega l\u00e6gri en \u00ed \u00fe\u00e9ttum RBSiC. \u00deensla er l\u00edtil. S\u00fa samsetning, \u00e1samt n\u00edtr\u00ed\u00f0bindingu, er \u00e1st\u00e6\u00f0an fyrir \u00fev\u00ed a\u00f0 h\u00fasg\u00f6gnin \u00feola upphitun og k\u00f3lnun \u00e1n \u00feess a\u00f0 f\u00e1 \u00f6rsm\u00e1a sprungul\u00ednu \u00e1 \u00feri\u00f0judegi.<\/p>\n
Efnafr\u00e6\u00f0ilega er \u00fea\u00f0 seigt \u00ed m\u00f6rgum i\u00f0na\u00f0arumhverfum. Br\u00e1\u00f0i\u00f0 \u00e1l og kyr\u00f3l\u00edt eru fr\u00e6gt d\u00e6mi: SiC me\u00f0 n\u00edtr\u00ed\u00f0bindingu var\u00f0 efni\u00f0 sem vali\u00f0 var fyrir hli\u00f0arveggir \u00ed afoxunarsellum, \u00fev\u00ed kolefni\u00f0 brann upp og ox\u00ed\u00f0steinninn entist ekki. \u00dea\u00f0 \u00feolir einnig betur slitskemmdir, margar sl\u00f6ggjar og \u00f3hreinan gas \u00ed s\u00edkl\u00f3num en leirbundin SiC-m\u00farsteinn. \u00dea\u00f0 er \u00fe\u00f3 ekki \u00f3dau\u00f0legt. Sterk l\u00fatn, l\u00e9leg n\u00edtrering me\u00f0 eftirliggjandi fr\u00edu k\u00edsli og \u00f3stj\u00f3rnu\u00f0 oxun \u00e1 heita andlitinu munu samt ey\u00f0a \u00fev\u00ed.<\/p>\n
Kyndingarf\u00f6r\u00f0un er daglegt brau\u00f0. Mottur, pl\u00f6tur, settarar, staurar og bj\u00e1lkar \u00ed salernisv\u00f6rum, bor\u00f0b\u00fana\u00f0i, rafmagns postul\u00edni og t\u00e6knilegum keramik. Bori\u00f0 saman vi\u00f0 kordier\u00edt f\u00e6r\u00f0u h\u00e6rri hita\u00feol, betri bur\u00f0argetu, \u00feynnri \u00feversni\u00f0 og minna dautt mass \u00ed ofninum. \u00deessi s\u00ed\u00f0asta sta\u00f0h\u00e6fing er ekki lj\u00f3\u00f0list. Minni massa \u00ed ofnb\u00fana\u00f0i \u00fe\u00fd\u00f0ir meira magn af v\u00f6rum og minna eldsneyti \u00ed hverjum hring.<\/p>\n
\u00c1l er hitt st\u00f3ra heimili\u00f0. Hli\u00f0arveggsblokkir \u00ed pottl\u00ednum \u00feurfa varmalei\u00f0ni, v\u00e9lr\u00e6na styrk og vi\u00f0n\u00e1m gegn ba\u00f0efnafr\u00e6\u00f0i. NSiC sinnir \u00fev\u00ed verki \u00e1 ver\u00f0i sem verksmi\u00f0jur geta s\u00e6tt sig vi\u00f0. Ne\u00f0ri hluti stafns \u00ed sprengikraftsofni, slitbelti \u00ed \u00fargang-til-orku ferlum og s\u00edkl\u00f3nf\u00f3\u00f0ringar \u00ed n\u00e1muvinnslu e\u00f0a orkuframlei\u00f0slu byggja \u00e1 s\u00f6mu r\u00f6kum: har\u00f0korna SiC, bindiefni sem \u00feolir hita og form sem h\u00e6gt er a\u00f0 setja upp sem m\u00farstein e\u00f0a steyptan hlut.<\/p>\n
Slitasv\u00e6\u00f0i koma einnig fram \u2014 fl\u00edsar, \u00fa\u00f0ap\u00edpur, d\u00e6luhlutar \u2014 \u00feegar umhverfi\u00f0 er heitt og sl\u00edfandi en \u00fe\u00fa \u00fearft ekki n\u00e6stum t\u00f3ma porosity \u00ed bindu\u00f0u SiC. Ef slampi\u00f0 er kalt og eini \u00f3vinurinn er rennisl\u00edfin, endist \u00fe\u00e9tt SiSiC-f\u00f3\u00f0run oft lengur. Ef \u00f3vinurinn er hiti \u00e1samt sliti og hitahv\u00f6rfum, byrjar NSiC a\u00f0 vir\u00f0ast snjall.<\/p>\n
K\u00edsilkarb\u00ed\u00f0 sem er bundi\u00f0 me\u00f0 vi\u00f0brag\u00f0sbinding er \u00fe\u00e9ttara, sterkara og me\u00f0 minni innri spennu. \u00dea\u00f0 hentar einstaklega vel til a\u00f0 framlei\u00f0a bj\u00e1lka, r\u00fallur og n\u00e1kv\u00e6mnis\u00feolparta vi\u00f0 hitastig undir um 1350\u20131380 \u00b0C. Yfir \u00fev\u00ed er frj\u00e1lst k\u00edsill drottnandi. NSiC hefur ekki \u00feann m\u00e1lmpoel \u00ed \u00f6rbyggingunni, svo \u00fea\u00f0 heldur \u00e1fram a\u00f0 starfa vi\u00f0 h\u00e6rri hita. \u00dea\u00f0 er einnig raunh\u00e6fasta vali\u00f0 fyrir st\u00f3r eldfast form \u00fear sem innrennsli k\u00edsils \u00ed risast\u00f3ran kubb er ekki tilgangurinn.<\/p>\n
Endukristalla\u00f0 SiC \u00feolir enn h\u00e6rri hita og helst hreinna \u00ed sumum ofnloftum, en \u00fea\u00f0 er poraslegri og yfirleitt veikara. Ox\u00ed\u00f0bundi\u00f0 SiC er \u00f3d\u00fdrara en tapar \u00ed hita\u00feoli og h\u00f6gg\u00feoli. Sintera\u00f0 SiC er hinn d\u00fdri, \u00fe\u00e9tti fr\u00e6ndi og ver\u00f0lagt \u00ed samr\u00e6mi vi\u00f0 \u00fea\u00f0. NSiC er \u00ed flokknum \u00fear sem verksmi\u00f0jur \u00feurfa SiC-frammist\u00f6\u00f0u \u00ed st\u00f3rum stykkjum \u00e1n \u00feess a\u00f0 kaupa ranns\u00f3knarstofu-keramik.<\/p>\n
\u00d3fullkominn n\u00edtrering er hinn \u00fe\u00f6gli mor\u00f0ingi. Blokk getur liti\u00f0 vel \u00fat a\u00f0 utan en fali\u00f0 eftirbleiki k\u00edsil e\u00f0a veikt kjarna. \u00cd \u00e1lfrumu veldur \u00fea\u00f0 snemma t\u00e6ringu. \u00cd ofnpl\u00f6tu ver\u00f0ur \u00fea\u00f0 oxun sem myljar yfirbor\u00f0i\u00f0 \u00ed duft og dregur \u00far styrknum. Raki \u00ed porositykri byggingu, sem svo er brenndur hratt, er anna\u00f0 klass\u00edskt d\u00e6mi. Gufan hefur engan \u00e1huga \u00e1 framlei\u00f0slu\u00e1\u00e6tlun \u00feinni.<\/p>\n
F\u00f3lk ofhitnar einnig \u00fe\u00e9ttan hugsunarh\u00e1tt \u00e1 porosity-stigi. NSiC er ekki loku\u00f0 r\u00f6r. Ef lofti\u00f0 getur komist inn skiptir oxun og \u00fe\u00e9ttiefnafr\u00e6\u00f0i m\u00e1li. Og ef notkunin er h\u00e1hra\u00f0a slurry vi\u00f0 h\u00f3flega hitastig g\u00e6tir\u00f0u keypt \u00fe\u00e9r tryggingu gegn varmaskoki sem \u00fe\u00fa \u00feurftir ekki.<\/p>\n
Ekki senda \u201cSiC-m\u00farstein\u201d og vona a\u00f0 \u00fea\u00f0 dugi. Kalla\u00f0u \u00fea\u00f0 n\u00edtr\u00ed\u00f0bundi\u00f0. Gef\u00f0u h\u00e1markshitastig, andr\u00famsloft, \u00e1lag, hringt\u00edma og efnasamsetningu \u2014 \u00e1lbat\u00edu, alkalagufu, flug\u00f6sku, glersteypu, hva\u00f0 sem raunverulega snertir hlutinn. Spyr\u00f0u um \u00fe\u00e9ttleika, s\u00fdnilega porosity, heitt brotmod\u00fal og eftirstandandi frj\u00e1lst k\u00edsil. Fyrir ofnb\u00fana\u00f0 skaltu spyrja hvort hluturinn s\u00e9 f\u00ednkorn\u00f3tt steypupl\u00e1stur (slip-cast) e\u00f0a gr\u00f3fur pressa\u00f0ur. \u00deessar tv\u00e6r v\u00f6rur slitna ekki n\u00e9 lei\u00f0a hita \u00e1 sama h\u00e1tt.<\/p>\n
Nitr\u00ed\u00f0bundi\u00f0 SiC er efni\u00f0 sem \u00fe\u00fa notar \u00feegar ox\u00ed\u00f0b\u00fana\u00f0ur er or\u00f0inn \u00fereyttur, en vi\u00f0brag\u00f0bundi\u00f0 SiC er of takmarka\u00f0 af hitastigi e\u00f0a of d\u00fdrt \u00ed st\u00f3rum hlutum, og verksmi\u00f0jan \u00fearf samt a\u00f0 vera \u00ed gangi. \u00dea\u00f0 er ekki gl\u00e6silegt. \u00dea\u00f0 er platan sem kemur beint \u00far ofninum, hli\u00f0veggurinn sem hn\u00edgur ekki og f\u00f3\u00f0ri\u00f0 sem er enn\u00fe\u00e1 \u00fear eftir s\u00ed\u00f0ustu herfer\u00f0. Tilgreindu flokkinn mi\u00f0a\u00f0 vi\u00f0 \u00e1lagi\u00f0 og hann helst \u00f3breyttur.<\/p>","protected":false},"excerpt":{"rendered":"
Hotter Than RBSiC, Tougher Than the Old Bricks: A Practical Guide to Nitride Bonded Silicon Carbide Nitride bonded silicon carbide does not get the same attention as reaction bonded SiC or sintered SiC. That is fine. It is busy holding up kiln cars, lining aluminum cells, and taking abrasion that oxide-bonded brick cannot survive. I […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-54","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/posts\/54","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/comments?post=54"}],"version-history":[{"count":2,"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/posts\/54\/revisions"}],"predecessor-version":[{"id":56,"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/posts\/54\/revisions\/56"}],"wp:attachment":[{"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/media?parent=54"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/categories?post=54"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nitridebondedsic.com\/is\/wp-json\/wp\/v2\/tags?post=54"}],"curies":[{"name":"vp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}