Spheroidized cov ntsiab lus feem ntau muaj cov khoom nram qab no:
(1) Muaj ib los yog ob lub valence electrons nyob rau hauv lub sab nrauv electron plhaub ntawm ib lub caij, thiab 8 electrons nyob rau hauv lub plhaub innermost. Cov qauv hluav taws xob no ua rau lub caij muaj kev sib raug zoo nrog cov sulfur, oxygen thiab carbon, uas qhia txog kev ruaj ntseg ntawm cov khoom thiab tuaj yeem txo cov leej faj thiab cov pa oxygen hauv qhov luv nqi.
(2) Lub solubility ntawm cov ntsiab lus nyob rau hauv molten hlau yog tsawg thiab muaj ib tug tseem ceeb nyiam sib cais thaum lub sij hawm solidification txheej txheem.
(3) Txawm hais tias nws muaj qee yam affinity nrog carbon, nws solubility nyob rau hauv graphite lattice yog tsawg. Raws li cov yam ntxwv saum toj no, Mg, Ce, Y, thiab Ca yog cov ntsiab lus spheroidizing zoo.
Ua ntej, lub vapor siab nyob rau hauv cov hlau molten yog siab, ua rau cov hlau molten effervescent. Lub atomic qhov hnyav thiab qhov ceev ntawm magnesium yog me dua li cov hlau molten, nrog lub melting point ntawm 650 degrees thiab lub boiling point ntawm 1108 degrees. Ntawm qhov ua haujlwm kub ntawm cov hlau molten, lub vapor siab tsim los ntawm magnesium yog siab heev (ntau tshaj 1Mpa). Lub tshav kub ntawm fusion ntawm magnesium yog 21J / g thiab latent cua sov ntawm evaporation yog 406J / g. Yog li ntawd, thaum magnesium ntxiv rau molten hlau, nws yuav vaporize thiab ua rau cov hlau molten churn.
Qhov thib ob, nws muaj kev sib raug zoo nrog cov sulfur thiab oxygen. Lub generated MgO thiab MgS muaj ib tug siab melting point thiab ib tug ceev npaum li cas me dua hlau, ua rau lawv yooj yim cais los ntawm molten hlau. Yog li ntawd, cov ntsiab lus ntawm leej faj thiab yaj hauv molten hlau tom qab kev kho magnesium yog tsawg heev;
Thib peb, muaj kev nyiam sib cais hauv graphite thaum lub sij hawm solidification txheej txheem ntawm molten hlau. Thaum nws cov seem seem nyob rau hauv cov hlau molten tshaj {{0}}.035%, cov hmoov tuaj yeem raug spheroidized. Txawm li cas los xij, thaum cov nyiaj seem ntawm magnesium ntau tshaj 0.07%, ib feem ntawm magnesium cais ntawm cov ciam teb. , thiab cov tshuaj tiv thaiv exothermic tshwm sim nrog cov pa roj carbon, phosphorus, thiab lwm yam nyob rau hauv cov ciam teb ntawm grain los tsim MgC2, Mg2C3, Mg3P2, thiab lwm yam. Thaum cov nyiaj seem ntawm magnesium yog loj, cov intergranular carbides nce.
