Xim Thiab Cov Khoom Ntawm Silicon Carbide
Cov xim thiab cov khoom ntawm silicon carbidePure silicon carbide yog xim tsis muaj xim thiab pob tshab siv lead ua, muaj xim silicon carbide muaj pos huab xim, lub teeb daj, lub teeb ntsuab, tsaus ntsuab, lub teeb xiav, tsaus xiav thiab txawm dub, lub degree ntawm transparency txo nyob rau hauv lem. Silicon carbide feem ntau muab faib ua dub silicon carbide (feem ntau siv code C hauv Suav teb) thiab ntsuab silicon carbide (code GC) ob pawg. Uas los ntawm cov xim pos huab mus rau tsaus ntsuab SiC raug cais ua ntsuab silicon carbide; Tsaus xiav rau dub yog cais raws li dub silicon carbide.Qhov laj thawj rau cov xim ntawm silicon carbide tsis to taub tag nrho. Nws yog feem ntau ntseeg hais tias nws muaj feem xyuam rau lub hav zoov ntawm ntau yam impurities. Thaum cov pa roj carbon ntau yaj hauv cov khoom siv lead ua, SiC siv lead ua yog xim dub; Aluminium muaj kev cuam tshuam zoo rau cov xim ntawm SiC, uas tuaj yeem ua rau cov khoom siv lead ua xim av-dub lossis xim dub; Boron tuaj yeem ua rau SiC siv lead ua dub; Lub xub ntiag ntawm hlau tsis cuam tshuam rau kev tsim ntawm ntsuab silicon carbide; Qee lub ntiaj teb tsis tshua muaj oxides (xws li Ce2O3, thiab lwm yam) tuaj yeem yog ntsuab lossis tsaus ntsuab hauv SiC crystals. Tsis tas li ntawd, dispersion ntawm nitrogen atoms nyob rau hauv SiC crystals yuav ua rau cov crystals tig ntsuab. Qhov siab dua qhov concentration ntawm nitrogen atoms, qhov xim ntawm SiC muaju tsaus. Xim thiab cov khoom ntawm sicNws muaj qee qhov kev sib raug zoo ntawm cov xim ntawm silicon carbide thiab hom crystallization. Ntsuab silicon carbide yog hom 6H, qee qhov muaj 5% ~ 10% ntawm 15R hom; Dub silicon carbide kuj tseem yog hom 6H, tab sis muaj ntau hom 15R thiab 4H (saib Table 2-3-1). Xim thiab cov khoom ntawm silicon carbide.
Los ntawm cov tshuaj muaj pes tsawg leeg, nws tuaj yeem pom tias cov silicon carbide dub muaj dawb Si, C (graphite-zoo li), Fe203, MgO, Al203 thiab lwm yam impurities feem ntau siab dua ntsuab silicon carbide (saib Table 2-3-2). Tab sis qhov no tsis zoo, dub silicon carbide nyob rau hauv SiC cov ntsiab lus yog siab tshaj ntsuab silicon carbide kuj yog ib yam khoom; Tsis muaj xim pob tshab silicon carbide tsis tas yuav siab hauv SiC, thiab feem ntau muaj SiO2 ntau dua. Silicon carbide xim thiab cov yam ntxwv
Dub thiab ntsuab silicon carbide muaj cov khoom sib txawv me ntsis. Nws yog feem ntau ntseeg tias piv nrog ob, ntsuab silicon carbide yog nyuaj thiab nkig, thiab dub silicon carbide yog tougher thiab me ntsis softer. Muaj ib pab pawg sib piv cov ntaub ntawv: ntsuab SiC Vickers microhardness 32000 ~ 34000MPa, microbrittleness Performance index 7.5 ~ 9; Dub SiC yog 31000 ~ 328000 MPa thiab 6.2 ~ 8.0.Green SiC yog txawv ntawm dub SiC manufacturing txheej txheem cov yam ntxwv yog: ① kev siv cov ntaub ntawv raw khoom purer; ② ntsev ntxiv rau cov khoom xyaw. Silicon carbide refractories feem ntau siv cov xim dub silicon carbide ua raw cov ntaub ntawv, ib qho yog nws lub siab toughness, thiab lwm yam yog pheej yig dua li ntsuab silicon carbide nyob rau hauv nqe.Green thiab dub silicon carbide hmoov zoo yog feem ntau txheeb xyuas los ntawm tshuaj ntsuam xyuas, cov qub SiO2, Fe203, cov ntsiab lus tsawg, tom kawg yog siab. Xim thiab cov khoom ntawm silicon carbide