Cov ntaub ntawv refractory rau aluminium melting furnace linings feem ntau yog khaws cia ntawm qhov kub thiab txias hauv qab 1000 degree. Fluorspar los yog barite thiab lwm yam khoom siv sintering thiab cov tshuaj tiv thaiv ntub dej ntxiv rau cov ntaub ntawv refractory no los txhawb kev kub siab sintering ntawm cov ntaub ntawv thiab txhim kho kev tiv thaiv rau txhuas kua nkag. Txawm li cas los xij, thaum lub cub tawg yog overheated rau qee qhov laj thawj, cov additives no tuaj yeem ua rau ntxov ntxov corrosion ntawm cov ntaub ntawv refractory. Txhawm rau kom kov yeej qhov teeb meem ntawm kev xeb ntxov ntxov ntawm cov ntaub ntawv refractory rau aluminium melting furnace linings, a (CaO-Al2O3) calcium aluminate refractory castables nrog calcium aluminate ua aggregate thiabcalcium aluminate cementraws li binder tau tsim. Feem ntau CAA yog tsim los ntawm melting raw cov ntaub ntawv nrog cov khoom piv ntawm Al2O3 rau CaO CaO/Al2O3=1 los yog 0.7 (molar ratio) thiab crushing rau hauv sib txawv particle loj. Txij li thaum CAA yog tsim los ntawm cov txheej txheem melting, nws pom meej porosity yuav luag xoom. Nyob rau hauv CAA cov ntaub ntawv, cov ntxhia theem feem ntau yog CaO-Al2O3, nrog ib tug melting point ntawm 1600 degree.
Calcium aluminate cement (abbreviated li CAC) tuaj yeem npaj los ntawm sintering thiab hluav taws xob melting txheej txheem, thiab nws cov tshuaj muaj pes tsawg leeg yog hais txog CaO27%, Al2O371%. Cov txiaj ntsig ntawm kev sib piv crucible self-etching test ntawm CAA castables thiab castables zoo tib yam ntawm 800 degree, 72h nrog AZ8GU aluminium alloy qhia tias CAC-bonded castables muaj peev xwm tiv thaiv tau zoo heev. Ntawm qhov tsis sib xws, CAC-bonded phaj zoo li alumina castables tuaj yeem nkag mus tob rau hauv nws cov qauv los ntawm aluminium alloy yaj, thiab muaj qhov pom tseeb corundum (-Al2O3) tiam. Cov txiaj ntsig kev sim kuj tseem qhia tau tias cov kua txhuas txhuas nkag mus tob rau hauv cov av nplaum castable nrog cov neeg sawv cev los tiv thaiv, txawm tias cov av nplaum castable nrog CAA ntxiv.
Nws tau raug lees paub tias kev sib cuam tshuam ntawm cov hlau yaj thiab cov khoom siv refractory nyob rau hauv aluminium smelting rauv yog qhov nkag ntawm cov yaj mus rau hauv lub qhov hws hauv cov qauv refractory ntawm lub qhov cub hauv ob sab phlu, ua rau txo qis ntawm SiO2 thiab / lossis aluminium oxides. tsim corundum (-Al2O3). Nyob rau hauv cov ntaub ntawv ntawm sodium-nplua nuj alloys los yog sodium-nplua nuj alkali ntsev, -Al2O3 yog tsim, uas ua rau cov aluminium-nplua nuj refractory hauv ob sab phlu kom tev tawm thiab ua ntej ua kev puas tsuaj. Txij li thaum CAA cov ntaub ntawv yuav luag tsis nkag los ntawm cov kua txhuas, yuav luag tsis muaj teeb meem ntawm cov txheej txheem tev thiab ua kom puas tsuaj rau cov ntaub ntawv refractory.
Cov txiaj ntsig ntawm qhov kev sib piv kuj qhia tau hais tias qhov permeability ntawm CAA low-cement refractory castables tsis muaj cov tshuaj tiv thaiv dej yog tib yam li cov tsoos alumina-based low-cement castables nrog BaSO4 (anti-wetting agent), thiab cov qub tuaj yeem. siv rau ntawm qhov kub txog li 1350 degree, uas ua kom ntseeg tau tias txawm tias thaum lub qhov cub kub dhau los, nws yuav tsis ua rau muaj kev xeb ua ntej ntawm lub qhov cub. refractory hauv ob sab phlu. Qhov no qhia tau hais tias CAA low-cement castables nrog CAA as aggregate thiab Calcium aluminate cement li binder yog tag nrho sib xws nrog cov kev siv ntawm aluminium smelting furnaces. Cov txiaj ntsig ntawm lwm cov kev tshawb fawb (500 degree, 100h CO erosion resistance test) qhia tau tias cov hlau tsis muaj CAA muaj qhov zoo heev CO yaig tiv thaiv tom qab cua sov rau 800 degree, qhia tias CAA castables nrog CAA li aggregate thiab CAC li binder kuj siv tau nyob rau hauv lub petrochemical kev lag luam.
