Aluminium oxide
Khoom: dawb khoom insoluble nyob rau hauv dej, odorless, tasteless, nyuaj heev, yooj yim rau nqus noo noo tsis delixing (kub ya raws).Alumina yog ib hom amphoteric oxide (corundum yog α-puab thiab belongs rau lub densiest hexagonal packing, yog ib tug inert compound, me ntsis soluble nyob rau hauv acid thiab alkali corrosion kuj [1]), soluble nyob rau hauv inorganic acid thiab alkaline daws, yuav luag insoluble nyob rau hauv dej. thiab non-polar organic solvents;txheeb ze ntom ntom (d204) 4.0;Melting point: 2050 ℃.
Cia: Khaws cia thiab qhuav.
Siv: Siv ua tshuaj reagent, organic solvent dehydration, adsorbent, organic tshuaj tiv thaiv catalyst, abrasive, polishing tus neeg saib xyuas, raw khoom rau smelting aluminium, refractory
Cov khoom xyaw tseem ceeb
Alumina muaj cov ntsiab lus txhuas thiab oxygen.Yog tias bauxite raw cov ntaub ntawv los ntawm kev kho tshuaj, tshem tawm cov oxides ntawm silicon, hlau, titanium thiab lwm yam khoom yog ntshiab alumina raw cov ntaub ntawv, Al2O3 cov ntsiab lus feem ntau yog ntau tshaj 99%.Cov ntxhia theem yog tsim los ntawm 40% ~ 76% γ-Al2O3 thiab 24% ~ 60% α-Al2O3.γ-Al2O3 hloov mus rau α-Al2O3 ntawm 950 ~ 1200 ℃, nrog lub ntim tseem ceeb shrinkage.
aluminium oxide (aluminium oxide) yog ib hom inorganic, tshuaj hom Al2O3, yog ib hom kev sib txuas siab hardness, melting point ntawm 2054 ℃, boiling point ntawm 2980 ℃, ionized siv lead ua nyob rau hauv high kub, feem ntau siv nyob rau hauv lub tsim ntawm refractory ntaub ntawv. .
Muaj alumina yog npaj los ntawm bauxite (Al2O3·3H2O) thiab diaspore.Rau Al2O3 nrog siab purity yuav tsum tau, nws yog feem ntau npaj los ntawm cov tshuaj.Al2O3 muaj ntau homogenous heterocrystals, muaj ntau tshaj 10 paub, muaj tsuas yog 3 hom siv lead ua, xws li α-Al2O3, β-Al2O3, γ-Al2O3.Ntawm lawv, cov qauv thiab cov khoom sib txawv, thiab α-Al2O3 yuav luag tag nrho hloov mus rau α-al2o3 ntawm qhov kub siab tshaj 1300 ℃.
Lub cev muaj zog
InChI = 1 / Al 2 o / rAlO ₂ / c2-1-3
Molecular Luj: 101.96
Melting point: 2054 ℃
Kub taw tes: 2980 ℃
Qhov ceev: 3.97g / cm3
Loose packing ceev: 0.85 g / mL (325 mesh ~ 0) 0.9 g / mL (120 mesh ~ 325 mesh)
Crystal qauv: hex tripartite system
Solubility: insoluble nyob rau hauv dej ntawm chav tsev kub
Hluav taws xob conductivity: Tsis muaj hluav taws xob conductivity ntawm chav tsev kub
Al₂O₃ yog ib qho siv lead ua ionic
Alumina ib feem siv ---- dag corundum
Corundum hmoov hardness yuav siv tau raws li abrasive, polishing hmoov, kub sintered alumina, hu ua dag corundum lossis dag gemstone, tuaj yeem ua los ntawm cov neeg kho tshuab bearings lossis watches hauv pob zeb diamond.Alumina kuj tseem siv los ua cov khoom kub kub refractory, ua refractory cib, crucible, porcelain, dag gems, alumina kuj yog raw khoom ntawm txhuas smelting.Calcined aluminium hydroxide tuaj yeem tsim γ-.Gamma-al ₂O₃ (vim nws muaj zog adsorption thiab catalytic kev ua si) yuav siv tau raws li ib tug adsorbent thiab catalyst.Qhov tseem ceeb ntawm corundum, alpha-al ₂O₃.Lub tripartite siv lead ua nyob rau hauv cov duab ntawm lub thoob los yog lub khob hliav qab.Nws muaj iav luster los yog pob zeb diamond luster.Qhov ceev yog 3.9 ~ 4.1g / cm3, hardness yog 9, lub melting point yog 2000 ± 15 ℃.Insoluble hauv dej, thiab insoluble hauv acids thiab bases.Kub kub kuj.Tsis muaj xim pob tshab hais tias dawb jade, muaj cov kab ntawm trivalent chromium liab hu ua ruby;Cov xim xiav uas muaj ob -, peb - lossis plaub - valent hlau hu ua sapphire;Muaj me me ntawm ferric oxide tsaus grey, tsaus xim hu ua corundum hmoov.Nws tuaj yeem siv los ua cov kabmob rau cov cuab yeej precision, pob zeb diamond rau moos, sib tsoo lub log, polishes, refractories thiab hluav taws xob insulators.Brightly xim gemstones siv rau kho kom zoo nkauj.Synthetic ruby ib leeg siv lead ua laser khoom.Ntxiv nrog rau cov zaub mov ntuj, nws tuaj yeem ua los ntawm hydrogen thiab oxygen nplaim melting aluminium hydroxide.
Alumina ceramic
Alumina muab faib ua calcined alumina thiab zoo tib yam muaj alumina.Calcined alumina yog ib qho tseem ceeb raw khoom rau zus tau tej cov antique bricks, thaum muaj alumina yuav siv tau rau zus tau tej cov pob zeb microcrystalline.Nyob rau hauv ib txwm glazes, alumina feem ntau yog siv los ua kom dawb.Kev siv cov alumina tseem nce xyoo los ntawm xyoo raws li cov khoom qub cib thiab cov pob zeb microcrystalline tau nyiam los ntawm kev ua lag luam.
Yog li ntawd, alumina ceramics tau tshwm sim hauv kev lag luam ceramic - alumina ceramics yog ib hom khoom siv ceramic nrog Al₂O₃ ua cov khoom tseem ceeb thiab corundum ua lub ntsiab crystalline theem.Vim hais tias ntawm nws cov neeg kho tshuab muaj zog, siab hardness, siab zaus dielectric poob, kub rwb thaiv tsev tsis kam, tshuaj corrosion kuj thiab zoo thermal conductivity thiab lwm yam zoo ntawm cov kev kawm zoo heev.
