Hauv kev ua haujlwm refractory, cov lus "Qauv Alumina"Thiab" actuagas "yog buzzwords, raws li lawv tau ua qhov tseem ceeb ntawm qhov sib txawv ntawm ob thiab seb lub hom phiaj lus no yog tsim nyog.
Ua ntej, nws yog qhov tseem ceeb kom paub meej dab tsi tau rov qab alumina, siv nyob rau hauv refractory cov ntaub ntawv. Nws yog cov khoom tau los ntawm calcining aluminium hydroxide lossis muaj kev lag luam alumina ntawm qhov kub thiab txias, ib nrab lossis hloov tag nrho rau hauv- al2O3Cov. Kev kho cov khoom siv nyob rau ntawm qhov ntsuas kub thiab txias kom ua rau muaj kev cuam tshuam nrog, ua rau poob dej ntawm crystallization lossis volatile Cheebtsam. Dav dav hais, muaj txhuas oxide tau los ntawm cua sov aluminium kom tshem tawm cov dej ntawm crystallization, txawm tias nws yog feem ntau thermodynamically ruaj khov- al2O3, xws li - al2O3lossis ec - al2O3, yog suav tias yog cov txheej txheem alumina, feem ntau paub txog kev muaj tsheb alumina lossis kev lag luam alumina.
Lo lus "ua kom Alumina" muaj ob lub ntsiab lus. Alumina siv nyob rau hauv tsis nyob rau hauv tsis -}}}}}}} illalcants, thiab catalysts, feem ntau yog hais txog "activated alumina." Cov ntxeem tau zoo li no, cov khoom siv tsis muaj khoom siv muaj qhov chaw tshwj xeeb thaj tsam. Nws cov microporous sab nraud muaj cov khoom uas yuav tsum muaj rau catalysis, xws li kos duab, kev ua si saum npoo av, thiab zoo heev thermal stability. Yog li ntawd, nws tau siv dav siv raws li kev txhawb nqa thiab kev txhawb nqa catalyst muaj nyob hauv cov tshuaj lom neeg. Hom kev ua haujlwm no feem ntau yog tsim los ntawm ob hom khoom siv raw: {{{}} al₂o₃, tau los ntawm cua sov thiab feerite. Lwm tus yog pseudo- boehmite, ua los ntawm aluminates aluminates, ntsev txhuas, lossis ob qho tib si. Pom tseeb, hom kev ua haujlwm zoo li no tsis haum rau kev siv hauv ripractories. Ua kom Alumina rau refractories yuav tsum ua kom tau raws li cov hauv qab no:
1) muab alumina nrog -} al₂o₃ raws li thawj crystalline theem;
2) muaj thawj lub tshuab ua kom loj me me rau ntawm cov qib submicron;
3) Muaj lub lis lis grain morphology thiab loj faib hluav taws xob kom kaw.
Lo lus no, Ameslikas tau coined los ntawm almatis, sawv rau reactive alumina. Nws cov dav hlau yog nws lub peev xwm los tswj cov particle loj uas faib rau hauv cov submicron ntau thiab nws cov kev txhim kho sinterron thiab nws cov kev txhim kho. Nws cov haujlwm tau ntsuas los ntawm nws sinterability: editine alumina hmoov tau nias rau hauv pellets thiab sintered ntawm ib qho ntsuas kub, xws li 1540 degree, rau ib lub sijhawm. Qhov ze dua cov tuab ntom ntom ntawm lub resulting alumina sintered lub cev tau los ntawm theoretical density ntawm {}} al₂o₃, qhov siab dua nws cov haujlwm. Hauv Nyij Pooj, ua haujlwm Alumina yog tsuas yog hu ua "yooj yim- sintering alumina." Yog li - hu ua cov Alumina yog tsuas yog cov muaju me me uas muaj cov roj nyoos ntau dua li cov lag luam raw, ua rau nws yooj yim dua rau sinter.
Pom tseeb, tus me dua thawj cov siv lead ua me me ntawm alumina siv hauv cov khoom siv refractory, ntau dua nws cov kev ua si tshwj xeeb. Tom qab kev sib tsoo kom huv si kom tawg cov agglomerates, cov koom haum me me tuaj yeem siv los ua kom pom tus thawj cov siv lead ua loj. Piv txwv li, tus nruab nrab ntawm lub inch (d50) ntawm almatis's almatis's almatis's almatis's, thiab cl370 ua kom zoo li Aluminas yog ib txwm 0.5μm, 0.6μm, thiab 2.5μm, feem. Nyob rau hauv sib piv, cov nqi d50 tus nqi ntawm cov pa roj pemined alumina feem ntau yog ib txwm tshaj 3μm.
Lo lus "kev ua haujlwm" yog lub sijhawm xaiv tsa. Tam sim no, tsis muaj kev lees paub thoob ntiaj teb rau kev txwv rau qhov muaj peev xwm "nquag ntsuas," thiab feem ntau-}}}}}}}}}}}}}}}}}} Kev ntsuas kev kawm kom kim. Sinterability yog nyob ntawm ntau yam, suav nrog cov cheeb tsam tshwj xeeb, thiab yuav tsum tsis txhob txiav txim siab ntawm qhov loj me me. Thaum sib tham {4 4}}}}}}} microto₃ micropowders, kev lag luam zoo li tsis muaj zog ntxiv thiab muaj qhov ntau dua crystal. Txawm li cas los xij, siv cov lus sib koom ua ke "ALUMINED ALUMINA" los hais txog ib feem ntawm Alumina, thaum xa mus rau lwm qhov li "actived alumina," yog tsis txhob ntxig los sis kev tshawb fawb. Kev tsis muaj cov qauv yuav tsum tau siv los ua kom pom cov haujlwm thiab lwm yam khoom ntawm alumina micropowders.
