Magnesia alumina spinel tubali

Tubalan Magina na alumina spinel suna amfani da magnesia na farko da sinte magnesia alumina spinel yashi tare da rabon C/S na 0.4 azaman kayan albarkatu, tare da mahimmin ƙwayar 3mm. Girman barbashin magnesia yana ɗaukar manyan barbashi 3 ~ 1mm, <1mm matsakaiciyar barbashi da <0.088mm lafiya foda azaman sinadaran matakin uku. Yi amfani da ruwa mai datti na sulfite azaman wakili mai ɗaurewa, gauraya tare da rigar niƙa, da sifa ta latsa murfin bulo 300t. Bayan korewar jikin ya bushe, ana kunna shi a 1560 ~ 1590 ° C. Yakamata a sarrafa yanayi mai rauni na oxyidation yayin aiwatar da harbe -harben.

Manyan injina masu zafin zafin jiki da kwanciyar hankali mai ɗorewa na tubalin periclase-spinel sun fi na talakan magina alumina. Ƙarfin matsawa a zafin jiki na ɗakin shine 70-100MPa, kuma kwanciyar hankali na girgiza (1000 ℃, sanyaya ruwa) sau 14-19 ne. Za’a iya amfani da tubalin periclase-spinel a cikin babban yanayin zafin zafi na masu jujjuyawar lemun tsami mai aiki.

spinel na magnesium-aluminium na ƙasata yana ɗaukar matakai biyu na samarwa: nutsewa da haɗawa. Kayan albarkatun ƙasa galibi magnesite ne da alumina foda ko bauxite. Dangane da alamomi daban-daban na magnesia da alumina, an rarraba spinel mai arzikin magnesia da spinel mai arzikin aluminium a fannoni daban-daban.

1. Dangane da tsarin samarwa ko hanya: sintered magnesium aluminum spinel (sintered spinel) da fused aluminum magnesium spinel (fused spinel).

2. Dangane da kayan samar da kayan, ana iya raba shi zuwa: bauxite-tushen magnesia-aluminum spinel da alumina-tushen magnesia-aluminum spinel. (Sintering ko electrofusion)

3. Dangane da abun ciki da aiki, an raba shi zuwa: spinel mai arzikin magnesium, spinel mai arzikin aluminium da spinel mai aiki.

Magnesia alumina spinel tubalin kuma ana kiranta tubalin periclase-spinel, wanda aka yi da tsattsarkar fused magnesia ko tsattsarkar magnesia mai ƙyalli biyu da tsarkin da aka riga aka haɗa magnesia-aluminium spinel azaman manyan albarkatun ƙasa, ta amfani da madaidaicin sinadaran Samar da matsi mai ƙarfi da tsarin samar da wuta mai zafi. Idan aka kwatanta da tubalin magnesia-chromium, wannan magnesia-aluminum composite brick ba wai kawai yana kawar da lahani na hemivalent chromium ba, amma kuma yana da juriya mai kyau na lalata, juriya na rage-rage iskar shaka, juriya mai zafi da kwanciyar hankali. Babban siminti ne mai matsakaicin matsakaici Mafi kyawun kayan da ba a yarda da shi ba na chromium don yankin juyawa na murhun wuta. Hakanan an yi amfani da shi a cikin kayan aikin zafi mai zafi kamar ƙamshin lemun tsami, murhun gilashi, da kayan aikin tace mai daga cikin tanderu, kuma ya sami sakamako mai kyau.

Fihirisar jiki da sunadarai na tubalin magina-aluminium da aka samar sune: MgO 82.90%, Al2O3 13.76%, SiO2 1.60%, Fe2O3 0.80%, bayyanannen porosity 16.68%, ƙima mai yawa 2.97g/cm3, ƙarfin matsa lamba na al’ada 54.4MPa, Ƙarfin ƙarfi na 1400 6.0 XNUMXMPa.

An yi nasarar amfani da tubalin ƙarfe na Magnesium-aluminium a cikin yankin canzawa na murƙushe rotary ciminti, amma suna iya fuskantar ɓarna da ɓarnawar tsarin lokacin amfani da shi a yankin harbe-harben, yana da wahalar rataya akan fatar kiln, kuma suna da rashin juriya ga tururin alkali. da ciminti clinker ruwa lokaci permeability. Kuma talaucin ikon yin tsayayya da matsi na inji wanda lalacewar jikin kiln ya haifar yana iyakance aikace -aikacen a yankin harbi. A saboda wannan dalili, masu bincike sun ɓullo da tubalin magnesia-aluminum spinel tubalin da ya dace da yankin harbe-harben siminti rotary kilns. A lokacin harbe-harbe da amfani, wani ɓangare na Fe2+ a cikin tsarin jujjuyawar periclase-spinel an oxidized zuwa Fe3+. Daga baya, wani ɓangare na Fe2+ da Fe3+ a cikin baƙin ƙarfe-aluminum spinel ya bazu zuwa cikin periclase matrix don samar da MgOss. A lokaci guda, wasu Mg2+ a cikin matrix suma suna yaɗuwa a cikin ƙwayoyin ƙarfe-aluminium na ƙarfe-ƙarfe, kuma suna amsawa tare da ragowar Al2O3 daga bazuwar baƙin ƙarfe-aluminium don ƙirƙirar magnesium-aluminum spinel. Wannan jerin halayen suna tare da haɓaka ƙarar, wanda ke haifar da samuwar microcracks. Zuwa

Bricel-aluminum tubalin tubalin yana da kyawawan kaddarorin rataye da murƙushewar zafi. Daga cikin su, dalilin da yasa baƙin ƙarfe na aluminium na rataye da kyau akan fatar kiln yayi kama da na tubalin mafic-iron spinel. Hakanan saboda aikin CaO a cikin simintin siminti da ƙaƙƙarfan narkar da Fe2O3 a cikin periclase don ƙirƙirar lu’ulu’u waɗanda zasu iya jiƙa periclase. , Calcium ferrite wanda ke haɗe clinker da bulo na wuta tare. Dalilin kyakkyawan juriya na zafin zafi shine samuwar microcracks.

A cikin tsarin MgO-Al2O3, madaidaicin adadin Al2O3 a cikin periclase a 1600 ° C kusan 0 ne; da m bayani adadin a 1800 ° C ne kawai 5%, wanda shi ne mafi karami fiye da Cr2O3. A cikin tsarin MgO-Al2O3, kawai mahaɗin binary shine magnesium aluminum spinel. Matsayin narkewa na aluminium spinel spin ya kai 2135 ℃, kuma mafi ƙarancin yanayin zafi na MgO-MA shima 2050 ℃. Magnesium-aluminium spinel ma’adinai ne na halitta, wanda galibi ana samunsa a cikin ruwan yashi, don haka yana da kyakkyawan daidaiton sinadarai ga kayan halitta.

Modul of elasticity is small, magnesia alumina brick (0.12 ～ 0.228) × 105 MPa, yayin da tubalin magnesia shine (0.6 ～ 5) × 105MPa; MA na iya canja wurin MF daga periclase, kuma yana iya share FeO. Amsar ita ce kamar haka: FeO+MgO • AI2O3 → MgO+FeAl2O4, FeO+MgO → (Mg • Fe) O, MA yana jan Fe2O3 kuma yana faɗaɗa kaɗan kuma yana da babban narkewa. Spinel yana da wurin narkewa na 2135 ° C, kuma zafin zafin zafinsa na farko tare da periclase ya fi 1995 ° C. Haɗin biyun zai inganta aikin haɗin gwiwa na tubalin magnesia. Zazzabi mai laushi yana da girma, amma ƙirar spinel tana tare da haɓaka ƙarar, kuma tarawa da ikon sake kunnawa yana da rauni, don haka ana buƙatar zafin zafin wuta mafi girma. Excellent thermal juriya. babban ƙarfi. Ƙarfin yashwa mai ƙarfi.