Nrog rau kev maj mam nkag siab ntawm kev tswj hwm ib puag ncig hauv tebchaws thiab kev siv zog ntau dua, ntsuab chromium-dawb ib puag ncig tus phooj ywg alkaline refractories tau pom qhov zoo dua. Magnesia-aluminium spinel cib yog cov khoom lag luam uas siv nyob rau hauv qhov kev hloov pauv ntawm qhov loj thiab nruab nrab ntawm cov cement rotary kilns vim lawv qhov zoo ntawm lub zog siab, kub tsis kam, thermal shock resistance, thiab muaj zog thermal stress kuj tau lees paub thoob ntiaj teb. cov neeg siv sijhawm ntev. Nyob rau theem no, nws tseem yog thawj qhov kev xaiv rau cov khoom siv refractory rau kev hloov chaw. Hauv kev ua haujlwm no, cov txiaj ntsig ntawm pre-synthesized fused magnesia-aluminium spinel ntawm nws qhov kev ua tau zoo tau kawm.
1 xeem
1.1 Cov khoom siv raw
Qhov kev sim no siv sintered magnesia, fused magnesia, thiab fused magnesia aluminium spinel ua cov ntaub ntawv tseem ceeb.
1.2 Kev ntsuas qhov sib piv ntawm qhov ntxiv thiab qhov loj me ntawm magnesium aluminium spinel sib txawv
Ntsuas cov ntaub ntawv raws li proportioning yuav tsum tau. Ua ntej, ntxiv cov pellets rau hauv ntub zeb rau qhuav sib tov rau 2 mus rau 3 feeb, ntxiv 3 feem pua (w) lignin tov binder thiab sib tov rau 3 mus rau 5 feeb, ces ntxiv 0.088 mm nplua hmoov thiab sib tov rau. 8 mus rau 10 feeb. Txawm li cas los xij, cov hmoov zoo tau muab qhwv tag nrho ntawm cov pellets, tsis muaj cov khoom siv raw, tsis muaj av nkos, thiab txhais tes xav tias txawm thiab mos, thiab cov khoom tuaj yeem tawm. Nws yog tsim los ntawm 630 t hluav taws xob ntsia hlau xovxwm. Tom qab lub cev ntsuab qhuav ntawm 110 degree × 24 h, nws yog loaded rau hauv qhov kub kub qhov cub rau tua. Tom qab tag nrho ntawm 5 cov ntsiab lus kub kub tau khaws cia rau 8 teev, nws txias thiab tshem tawm ntawm qhov cub.
1.2 Kev ntsuas kev ua haujlwm
Kuaj lub ntim ntom ntom thiab pom tseeb porosity raws li GB / T 5998-2000, sim ua lub tshuab hluav taws xob raws li YB / T376. {{ 3}} ib.
2 Kev txheeb xyuas qhov tshwm sim
2.1 Kev cuam tshuam ntawm magnesium-aluminium spinel ntxiv rau cov khoom siv
2.1.1 Kev cuam tshuam ntawm qhov pom tseeb porosity thiab bulk ntom
Kev cuam tshuam ntawm tus nqi ntawm magnesium-aluminium spinel ntxiv rau qhov pom meej porosity thiab bulk ntom ntawm cov qauv.
2.1.2 Kev cuam tshuam ntawm lub zog compressive ntawm cov khoom ntawm chav tsev kub tom qab tua
Nws tuaj yeem pom tau tias nrog qhov nce ntawm magnesium-aluminium spinel, lub zog compressive ntawm cov qauv qhia tau hais tias qhov kev poob qis. Txawm hais tias qhov txo qis tsis loj, nws maj mam txo. Thaum cov nyiaj ntxiv (w) ntau dua 20 feem pua, lub zog txo qis dua pom tseeb.
2.1.3 Qhov cuam tshuam ntawm kev ua haujlwm tiv thaiv kev kub ntxhov
Nws tuaj yeem pom tau tias raws li tus nqi ntawm magnesium-aluminium spinel ntxiv nce, thermal poob siab tsis kam ntawm cov qauv maj mam nce. Thaum tus nqi ntawm magnesium-aluminium spinel (w) ntau dua 24 feem pua, cov thermal shock kuj zoo dua qub. Yuav luag tsis sawv lawm.
2.2 Kev cuam tshuam ntawm magnesia-aluminium spinel nrog ntau qhov sib txawv ntawm cov khoom ntawm cov khoom tom qab tua
2.2.1 Cuam tshuam txog bulk ntom thiab pom tseeb porosity
Nws tuaj yeem pom tau tias qhov me me ntawm cov magnesium-txhuas spinel cuam tshuam rau cov tuab tuab thiab pom porosity ntawm cov khoom. Qhov loj dhau los yog qhov me me dhau lawm tsis tsim nyog los txo qhov pom meej porosity thiab nce qhov ntom ntom. Qhov zoo tshaj plaws yog mus txog thaum lub particle loj nyob rau hauv lub sij hawm tsim nyog ntawm 3.5-1 hli. Qhov ntsuas qhov ntom ntom ntawm cov qauv B-1, B-2, B-3, thiab B-4 yog 2.94 g·cm-3 thiab 2.96 g·cm, raws li -3, 2.95 g·cm-3, 2.95 g·cm-3, qhov pom tseeb porosity yog 16.7 feem pua, 16.2 feem pua, 16.4 feem pua, 16.5 feem pua, raws li.
2.2.2 Kev cuam tshuam ntawm compressive zog ntawm chav tsev kub
Qhov loj me me ntawm magnesium-aluminium spinel cuam tshuam lub zog compressive ntawm chav tsev kub, thiab qhov loj me me uas tsim nyog yog qhov zoo los txhim kho lub zog compressive ntawm chav tsev kub, thiab qhov loj dua los yog me me tsis haum rau kev txhim kho lub zog compressive. ntawm chav tsev kub. Qhov nruab nrab chav tsev kub compressive zog ntawm cov qauv B-1, B-2, B-3, thiab B-4 yog 61.3 MPa, 68.5 MPa, 65.4 MPa, thiab 63.7 MPa, raws.
2.2.3 Qhov cuam tshuam ntawm kev ua haujlwm tiv thaiv kev kub ntxhov
Nrog rau qhov nce ntawm qhov loj me ntawm magnesium-aluminium spinel, thermal shock stability ntawm cov qauv qhia tau hais tias ib qho kev sib txawv ntawm thawj qhov nce thiab tom qab ntawd txo qis. Lub thermal shock resistance ntawm cov qauv B-1, B-2, B-3, thiab B-4 yog 14 zaug, 16 zaug, 12 zaug, thiab 9 zaug, raws li.
2.3 Kev tsom xam
Txij li lub ntim ntim ntawm qhov ntxiv fused magnesia-aluminium spinel (3.72 g·cm-1) yog siab dua li ntawm high-purity magnesia (3.25 g·cm-1), lub ntim ntom ntawm qhov ntxiv magnesia-aluminium spinel nce Nrog qhov nce, qhov pom meej porosity pom qhov kev poob qis. Thaum cov magnesia-aluminium spinel ntxiv rau ntau tshaj 20 feem pua, cov khoom yuav tsim cov spinel theem nrab thaum lub sij hawm firing txheej txheem, thiab lub cib lub cev yuav nthuav thiab microcracks yuav nce, uas ua rau ib tug txo nyob rau hauv volume ceev thiab nce nyob rau hauv pom porosity. Vim hais tias spinel thiab periclase yog tib yam equiaxed crystal system, thermal expansion coefficient ntawm magnesia-aluminium spinel yog 7.6 × 10-6, thiab cov periclase yog 13.5 × 10-6. M-MA cib feem ntau siv qhov zoo ntawm qhov sib txawv loj hauv thermal expansion coefficient ntawm ob. Qee tus lej ntawm micro-cracks yog tsim thaum lub sijhawm tua hluav taws thiab ua kom txias. Lub cim ntawm micro-cracks txhim kho cov thermal shock tsis kam ntawm cov khoom. Qhov tsim nyog ntawm micro-cracks tuaj yeem siv rau hauv kev siv. Tsis txhob thermal stress tshwm sim los ntawm qhov kub thiab txias hloov ntawm lub kiln thiab txo cov tev ntawm cov khoom. Txawm li cas los xij, ntau qhov micro-cracks yuav cuam tshuam rau lub zog ntawm cov khoom. Yog li ntawd, raws li tus naj npawb ntawm magnesium aluminium spinel nce, thermal shock kuj ntawm cov khoom txhim kho. Lub zog compressive ntawm chav tsev kub yog txo.
3 Kev xaus
(1) Nrog rau qhov nce ntawm cov magnesia-aluminium spinel, lub zog compressive ntawm magnesia-aluminium cib nyob rau hauv chav tsev kub yuav maj mam txo, thiab thermal shock kev ua tau zoo yuav maj mam txhim kho. Lub zog tag nrho lub ntom, pom meej porosity, thermal poob siab heev, thiab lwm yam ntxiv rau kev ntxiv 24 feem pua;
(2) Ntxiv magnesia-aluminium spinel los tsim cov spinel theem nrab nrog magnesia (M-MA) thaum lub sij hawm firing txheej txheem, ua rau ib tug tsim nyog tus nqi ntawm microcracks, uas yog zoo los txhim kho lub thermal shock kev ua tau zoo, tab sis lub zog yog txo;
(3) Tsim nyog nce qhov me me ntawm magnesium-aluminium spinel yog qhov zoo los txhim kho cov thermal poob siab. Qhov kev ntsuam xyuas yog tias qhov ntim ntom ntom ntawm cov khoom thaum qhov loj me yog 3. 5-1 hli ntxiv, qhov pom meej porosity yog qhov zoo tshaj plaws, lub zog yog nruab nrab, thiab thermal shock stability yog qhov zoo. .
