Cov hlau tsis tshua muaj hauv ntiaj teb tau siv dav hauv kev lag luam, thiab ntau dua purity tsawg lub ntiaj teb hlau yog siv los txiav txim siab lub cev thiab tshuaj lom neeg. Muaj plaub txoj kev ua kom huv huv tseem ceeb siv hauv chav kuaj, uas yog lub tshuab nqus tsev, lub tshuab nqus tsev distillation lossis sublimation, electromigration, thiab cheeb tsam melting.
Vacuum melting method
Cov hlau tsis tshua muaj lub ntiaj teb uas tsis tshua muaj vapor siab, xws li scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, gadolinium, terbium, thiab lutetium, yog melted thiab purified ntawm lub tshuab nqus tsev siab tshaj 10-6 Torr ntawm qhov kub thiab txias {{ 1}} degree siab dua qhov melting point ntawm cov hlau. Nyob rau hauv cov ntaub ntawv no, impurities nrog siab vapor siab xws li alkali hlau, alkaline ntiaj teb hlau, fluorides, thiab tsawg valent oxides (RO) yuav distilled tawm, tab sis cov nyhuv ntawm boiling point impurities xws li tantalum, hlau, vanadium, thiab chromium tsis zoo.
Vacuum distillation method
Kuj tseem hu ua lub tshuab nqus tsev sublimation. Distillation purification ntawm yttrium, gadolinium, terbium, thiab lutetium yog nqa tawm ntawm lub tshuab nqus tsev ntawm 10-6-10-9 degree C thiab qhov kub ntawm 1600-1725 degree C, thaum sublimation purification ntawm scandium, dysprosium, holmium, erbium, thulium, samarium, europium, thiab ytterbium yog nqa tawm ntawm 1550-1650 degree C. Cov kev mob no, hlau impurities nrog tsawg vapor siab xws li tantalum thiab tungsten, nrog rau cov tebchaw uas muaj carbon, nitrogen, thiab oxygen, yuav nyob twj ywm hauv crucible. Txoj kev no feem ntau yog siv ua ke nrog lub tshuab nqus tsev melting.
Txoj kev electromigration
Siv ncaj qha tam sim no rau lub ntiaj teb tsis tshua muaj hlau pas nrig hauv ultra-high nqus los yog inert cua, thiab tuav nws ntawm 100-200 degree qis dua qhov melting point ntawm cov hlau rau 1-3 lub lis piam. Raws li qhov kub thiab txias tam sim no hluav taws xob tam sim no, ntau yam impurity cov ntsiab lus sib sau ua ke ntawm cov pas ntsuas ntawm ob qhov kawg vim qhov sib txawv ntawm cov nqi zoo, diffusion coefficient, thiab kev txav mus los. Txiav tawm ob qho kawg ntawm qhov ntsuas pas nrig, thiab ua kom huv electromigration dua nyob rau hauv nruab nrab seem. Kev ua kom huv ntawm lanthanum, cerium, praseodymium, neodymium, gadolinium, terbium, yttrium, thiab lutetium siv cov txheej txheem electromigration hauv chav kuaj muaj txiaj ntsig zoo rau kev tshem tawm cov impurities xws li carbon, oxygen, thiab nitrogen.
Regional melting txoj kev
Tsis tshua muaj lub ntiaj teb hlau rods yog melted ntau zaus nyob rau hauv ib cheeb tsam melting rauv ntawm ib tug qeeb ceev ceev (xws li 0.4 mm/min rau yttrium purification), uas muaj ib tug tseem ceeb rau kev tshem tawm cov hlau impurities xws li hlau, txhuas. , magnesium, tooj liab, thiab npib tsib xee, tab sis tsis zoo rau oxygen, nitrogen, carbon, thiab hydrogen. Tsis tas li ntawd, electrolytic refining thiab cheeb tsam melting hluav taws xob tsiv teb tsaws ua ke txoj kev kuj muaj qee yam cuam tshuam rau purifying tsis tshua muaj ntiaj teb.
