Txhuas (Al) yog ib hom hlau uas tsis hnyav, dawb thiab nyiaj uas yog qhov thib peb muaj ntau tshaj plaws hauv lub ntiaj teb lub plhaub, tom qab tsuas yog oxygen thiab silicon xwb. Txawm li cas los xij, vim nws muaj zog heev rau kev ua haujlwm ntawm cov tshuaj lom neeg, nws yeej tsis tshwm sim hauv nws daim ntawv hlau ntshiab. Hloov chaw, nws pom muaj nyob rau hauv cov tshuaj sib xyaw, feem ntau yog nyob rau hauv bauxite ore, ib qho sib xyaw ntawm cov hydrated aluminium oxides suav nrog gibbsite (Al(OH)₃), boehmite (AlO(OH)), thiab diaspore.
Cov Txheej Txheem Refining hauv Ob Theem
Kev mus los ntawm bauxite nyoos mus rautxhuas purity siab muaj xws liob txoj kev lag luam sib txawv.
Theem ib yog Bayer txheej txheem, tsim tawm xyoo 1888. Bauxite uas raug tsoo yog sib xyaw nrog cov kua sodium hydroxide kub hauv qab kev nias, yaj cov zaub mov uas muaj txhuas thaum tseem tshuav cov khoom tsis huv xws li hlau oxides thiab silica. Cov kua sodium aluminate uas tshwm sim ces raug lim kom tshem tawm cov av nkos liab, muab cov siv lead ua los ntawm txhuas hydroxide, thiab calcined ntawm kwv yees li 1,100 ° C los tsim cov alumina dawb huv, lossis txhuas oxide (Al₂O₃). Ntau tshaj 90% ntawm lub ntiaj teb alumina tam sim no yog tsim los ntawm txoj kev no.
Theem ob yog txheej txheem Hall Héroult. Alumina muaj qhov kub yaj tshaj 2,000°C, ua rau electrolysis ncaj qha tsis yooj yim. Cov tshuaj yog yaj Al₂O₃ hauv cryolite uas yaj (Na₃AlF₆), uas txo qhov kub ua haujlwm mus txog li 950 ~ 1,000°C. Tom qab ntawd muaj hluav taws xob hla dhau qhov sib tov. Cov txhuas uas yaj yuav sib sau ua ke hauv qab (cathode), thaum cov pa oxygen sib xyaw nrog cov anodes carbon los tsim CO₂. Txoj kev electrolytic no tseem yog tib txoj kev lag luam rau kev tsim cov txhuas thawj, uas ua rau muaj hlau ntawm 99.5 ~ 99.8% purity.
Aluminium Muaj Cov Khoom Dab Tsi?
Txhuas ntshiab nws tus kheej muaj tsuas yog cov khoom Al, nrog tus lej atomic ntawm 13 thiab qhov hnyav atomic ntawm kwv yees li 26.98 g / mol. Kev lag luam ntshiab txhuas (98.8–99.7% Al) muaj cov cim me me ntawm hlau thiab silicon ua cov khoom tsis huv ntuj. Txawm li cas los xij, feem ntaucov ntawv thov vam khom rau cov hlau txhuas, qhov twg cov ntsiab lus tshwj xeeb raug ntxiv rau kom kho cov khoom siv kho tshuab.
Rau cov ntawv thov kev tsim kho, 6000 series (piv txwv li, 6061) siv magnesium thiab silicon ua nws cov ntsiab lus tseem ceeb, feem ntau yog 0.8 ~ 1.2% Mg thiab 0.400 ~ .8% Si. Cov hlau no muaj qhov sib npaug zoo heev ntawm lub zog nruab nrab, kev vuam zoo, thiab kev siv tshuab zoo dua.
Rau cov kev xav tau siab zog, 7000 series (piv txwv li, 7075) suav nrog zinc thiab tooj liab ua cov ntsiab lus tseem ceeb, nrog kwv yees li 5.16 ~ .1% Zn thiab 1.2 ~ 2.0% Cu. Lub T6 temper ntawm 7075 muab ze li ob npaug ntawm lub zog tensile ntawm 6061-T6, ua rau nws yog cov khoom siv xaiv rau aerospace thiab cov khoom ua haujlwm siab.
Muaj cov chromium, manganese, thiab titanium me me uas feem ntau pom muaj nyob rau hauv cov hlau ua lag luam, txhua yam ua lub luag haujlwm hauv kev ua kom cov noob zoo thiab tiv taus xeb. Kev nkag siab txog cov khoom sib xyaw ua ke ntawm txhua hlau yog qhov tseem ceeb rau kev xaiv cov khoom siv zoo rau kev ua haujlwm lossis kev tsim khoom tshwj xeeb.
Lub sijhawm tshaj tawm: Tsib Hlis-13-2026