1 Daim ntawv thov thiab kev tshawb fawb kev nce qib ntawm silicon carbide txheej hauv carbon / carbon thermal field cov ntaub ntawv
1.1 Daim ntawv thov thiab kev tshawb fawb nce qib hauv kev npaj crucible
Nyob rau hauv ib tug crystal thermal teb, lubcarbon / carbon cruciblefeem ntau yog siv los ua lub nkoj nqa rau cov khoom siv silicon thiab yog nyob rau hauv kev sib cuag nrog covquartz crucible, raws li pom nyob rau hauv daim duab 2. Kev ua hauj lwm kub ntawm cov pa roj carbon / carbon crucible yog hais txog 1450 ℃, uas yog raug rau ob erosion ntawm cov khoom silicon (silicon dioxide) thiab silicon vapor, thiab thaum kawg lub crucible yuav nyias los yog muaj lub nplhaib tawg, ua rau lub crucible tsis ua hauj lwm.
Ib txheej txheej carbon / carbon composite crucible tau npaj los ntawm cov txheej txheem tshuaj vapor permeation thiab cov tshuaj tiv thaiv hauv qhov chaw. Cov txheej txheej yog tsim los ntawm silicon carbide txheej (100 ~ 300μm), silicon txheej (10 ~ 20μm) thiab silicon nitride txheej (50 ~ 100μm), uas tuaj yeem cuam tshuam qhov corrosion ntawm silicon vapor ntawm sab hauv ntawm carbon / carbon composite crucible. Hauv cov txheej txheem tsim khoom, qhov poob ntawm cov khoom sib xyaw coated carbon / carbon composite crucible yog 0.04 hli rau ib lub cub tawg, thiab lub neej kev pab cuam tuaj yeem ncav cuag 180 lub sijhawm cub.
Cov kws tshawb fawb tau siv cov tshuaj tiv thaiv kab mob los tsim cov txheej txheem silicon carbide rau saum npoo ntawm carbon / carbon composite crucible nyob rau hauv tej yam kub thiab kev tiv thaiv ntawm cov cab kuj roj, siv silicon dioxide thiab silicon hlau ua raw khoom nyob rau hauv ib tug high-kub sintering rauv. Cov txiaj ntsig tau pom tias qhov kev kho kub kub tsis yog tsuas yog txhim kho lub purity thiab lub zog ntawm sic txheej, tab sis kuj zoo heev txhim kho qhov hnav tsis kam ntawm cov pa roj carbon / carbon sib xyaw, thiab tiv thaiv corrosion ntawm qhov chaw ntawm lub crucible los ntawm SiO vapor thiab volatile oxygen atoms nyob rau hauv lub monocrystal silicon cub. Lub neej kev pab cuam ntawm lub crucible yog nce los ntawm 20% piv nrog cov crucible uas tsis muaj sic txheej.
1.2 Daim ntawv thov thiab kev tshawb fawb kev nce qib hauv cov raj xa dej
Daim ntawv qhia lub tog raj kheej nyob rau saum lub crucible (raws li qhia hauv daim duab 1). Nyob rau hauv tus txheej txheem ntawm siv lead ua rub, qhov kub ntawm qhov sib txawv ntawm sab hauv thiab sab nraud yog qhov loj, tshwj xeeb tshaj yog nyob rau hauv qab ntawm qhov chaw ze tshaj plaws ntawm cov khoom siv silicon, qhov kub thiab txias yog qhov siab tshaj plaws, thiab corrosion los ntawm silicon vapor yog qhov hnyav tshaj plaws.
Cov kws tshawb fawb tau tsim cov txheej txheem yooj yim thiab zoo oxidation tsis kam ntawm cov lus qhia raj los tiv thaiv oxidation txheej thiab kev npaj. Ua ntej, ib txheej ntawm silicon carbide whisker yog nyob rau hauv-situ loj hlob nyob rau hauv lub matrix ntawm cov kev taw qhia raj, thiab ces ib tug tuab silicon carbide txheej txheej tau npaj, thiaj li hais tias ib tug SiCw kev hloov txheej tau tsim nyob rau hauv lub matrix thiab ntom silicon carbide nto txheej, raws li qhia nyob rau hauv daim duab 3. Nws tuaj yeem txo qhov kev ntxhov siab thermal tshwm sim los ntawm qhov tsis sib xws ntawm thermal expansion coefficient.
Kev tsom xam pom tau hais tias nrog kev nce ntawm SiCw cov ntsiab lus, qhov loj thiab cov kab nrib pleb hauv txheej txo qis. Tom qab 10h oxidation nyob rau hauv 1100 ℃ huab cua, qhov hnyav poob ntawm cov qauv txheej tsuas yog 0.87% ~ 8.87%, thiab oxidation kuj thiab thermal shock kuj ntawm silicon carbide txheej yog zoo heev. Tag nrho cov txheej txheem kev npaj ua tiav tsis tu ncua los ntawm cov tshuaj vapor deposition, kev npaj ntawm silicon carbide txheej yog yooj yim heev, thiab cov kev ua tau zoo ntawm tag nrho cov nozzle muaj zog.
Cov kws tshawb fawb tau npaj ib txoj hauv kev ntawm matrix ntxiv dag zog thiab txheej txheej ntawm graphite qhia raj rau czohr monocrystal silicon. Cov tau txais silicon carbide slurry yog uniformly coated nyob rau saum npoo ntawm graphite qhia raj nrog ib tug txheej thickness ntawm 30 ~ 50 μm los ntawm txhuam txheej los yog tshuaj tsuag txheej txheej, thiab ces muab tso rau hauv ib tug kub kub rau in-situ cov tshuaj tiv thaiv, cov tshuaj tiv thaiv kub yog 1850 ~ 2300 ℃, thiab lub tshav kub preservation yog 2 ~ 6h. SiC txheej txheej tuaj yeem siv tau rau hauv 24 hauv (60.96 cm) ib qho kev loj hlob siv lead ua rauv, thiab siv qhov kub thiab txias yog 1500 ℃, thiab pom tias tsis muaj qhov tawg thiab poob hmoov rau saum npoo ntawm graphite qhia lub tog raj kheej tom qab 1500h.
1.3 Daim ntawv thov thiab kev tshawb fawb nce qib hauv lub tog raj kheej rwb thaiv tsev
Raws li ib qho ntawm cov khoom tseem ceeb ntawm monocrystalline silicon thermal field system, lub tog raj kheej rwb thaiv tsev feem ntau yog siv los txo cov cua sov thiab tswj qhov kub thiab txias ntawm qhov chaw thermal. Raws li kev txhawb nqa ntawm cov phab ntsa sab hauv txheej txheej ntawm ib qho siv lead ua rauv, silicon vapor corrosion ua rau slag poob thiab tawg ntawm cov khoom, uas thaum kawg ua rau cov khoom tsis ua haujlwm.
Txhawm rau ntxiv dag zog rau silicon vapor corrosion tsis kam ntawm C / C-sic rwb thaiv tsev raj, cov kws tshawb fawb tau muab cov khoom siv C / C-sic puas rwb thaiv tsev rau hauv cov tshuaj vapor cov tshuaj tiv thaiv rauv, thiab npaj ntom silicon carbide txheej ntawm C / C-sic composite rwb thaiv tsev raj khoom. Cov txiaj ntsig tau pom tias, Cov txheej txheem tuaj yeem cuam tshuam zoo rau kev xeb ntawm cov pa roj carbon fiber ntau ntawm cov tub ntxhais ntawm C / C-sic composite los ntawm silicon vapor, thiab corrosion kuj ntawm silicon vapor yog nce los ntawm 5 mus rau 10 npaug piv nrog carbon / carbon composite, thiab kev pab cuam lub neej ntawm cov rwb thaiv tsev lub tog raj kheej thiab kev nyab xeeb ntawm thermal teb ib puag ncig zoo heev.
2. Cov lus xaus thiab kev cia siab
Silicon carbide txheejyog ntau thiab ntau lug siv nyob rau hauv carbon / carbon thermal teb cov ntaub ntawv vim nws zoo heev oxidation kuj nyob rau hauv kub. Nrog rau qhov loj ntawm carbon / carbon thermal teb cov ntaub ntawv siv nyob rau hauv monocrystalline silicon ntau lawm, yuav ua li cas los txhim kho lub uniformity ntawm silicon carbide txheej nyob rau saum npoo ntawm thermal teb cov ntaub ntawv thiab txhim kho cov kev pab cuam lub neej ntawm carbon / carbon thermal teb cov ntaub ntawv tau dhau los ua teeb meem ceev yuav tsum tau daws.
Ntawm qhov tod tes, nrog kev txhim kho ntawm kev lag luam monocrystalline silicon, qhov kev thov rau high-purity carbon / carbon thermal field cov ntaub ntawv kuj nce, thiab SiC nanofibers kuj tau loj hlob ntawm cov pa roj carbon fiber ntau hauv cov tshuaj tiv thaiv. Qhov loj ablation thiab linear ablation tus nqi ntawm C / C-ZRC thiab C / C-sic ZrC composites npaj los ntawm kev sim yog -0.32 mg / s thiab 2.57 μm / s, feem. Qhov loj thiab kab ablation tus nqi ntawm C / C-sic -ZrC composites yog -0.24mg / s thiab 1.66 μm / s, feem. C / C-ZRC composites nrog SiC nanofibers muaj cov khoom zoo dua. Tom qab ntawd, cov teebmeem ntawm cov pa roj carbon sib txawv ntawm kev loj hlob ntawm SiC nanofibers thiab cov txheej txheem ntawm SiC nanofibers ntxiv dag zog rau cov khoom ntawm C / C-ZRC composites yuav raug kawm.
Ib txheej txheej carbon / carbon composite crucible tau npaj los ntawm cov txheej txheem tshuaj vapor permeation thiab cov tshuaj tiv thaiv hauv qhov chaw. Cov txheej txheej yog tsim los ntawm silicon carbide txheej (100 ~ 300μm), silicon txheej (10 ~ 20μm) thiab silicon nitride txheej (50 ~ 100μm), uas tuaj yeem cuam tshuam qhov corrosion ntawm silicon vapor ntawm sab hauv ntawm carbon / carbon composite crucible. Hauv cov txheej txheem tsim khoom, qhov poob ntawm cov khoom sib xyaw coated carbon / carbon composite crucible yog 0.04 hli rau ib lub cub tawg, thiab lub neej kev pab cuam tuaj yeem ncav cuag 180 lub sijhawm cub.
Post lub sij hawm: Feb-22-2024