Xauv lub peev xwm ntawm Pyrolytic Graphite: Cov Khoom thiab Kev Siv

Pyrolytic graphite yog ib daim ntawv tshwj xeeb ntawm graphite nrog cov khoom tshwj xeeb, ua rau nws muaj txiaj ntsig zoo tshaj plaws. Tsab ntawv no rho mus rau hauv cov yam ntxwv, ntau lawm, thiab cov kev siv ntau yam ntawmPyrolytic graphite, Qhia tias yog vim li cas nws yog cov khoom siv ntawm kev xaiv rau kev xav tau cov txheej txheem thev naus laus zis. Peb yuav tshawb nws cov qauv tshwj xeeb, thermal thiab hluav taws xob, thiab yuav ua li cas cov no pab nws siv nyob rau hauv txhua yam ntawm hluav taws xob rau aerospace. Rau cov tub txawg zoo li Markson, nkag siab cov ntsiab lus no tuaj yeem muab cov kev sib tw hauv kev ua lag luam thoob ntiaj teb.

1. Pyrolytic graphite?

Pyrolytic graphiteyog ib qho tshwj xeeb, txiv neej tsim daim ntawv ntawm graphite tsim los ntawm cov txheej txheem hu ua vaportso chaw(CVD). Tsis zoo li cov graphite ntawm cov graphite lossis cov graphite,Pyrolytic graphiteyog cov khoom siv polycrystalline, lub ntsiab lus nws tau tsim los ntawm ntau ntau cov muaju graphite me me. Txawm li cas los xij, cov muaju no yogHeev Oriented, muabPyrolytic graphiteQee yam khoom tshwj xeeb tshaj plaws. Cov khoom siv zoo ib yam li graphite yog tsim thaum aHydrocarbonroj (zoo li methane) yog rhuab rau heevQhov Kub Siabnyob rau hauv ib qho chaw inert. Qhov no ua rau cov pa rojkev txiav txim, thiab tusCarbon atoms yog tso cov txheej txheej los ntawm txheej rau ntawm asubstrate.

Tus qauv txheej txheem no yog qhov tseem ceeb kom nkag siabPyrolytic graphiteCov. Nws zoo ib yam li muab tso rau ntau nplooj ntawv nyias nyias. Txhua daim ntawv sawv cev ib txheej ntawmhoob, qhov twgCarbon atoms yog nruj nreem sib raug zoo hauv hexagonal lattice. Cov hlua khi no nyob hauv lub dav hlau muaj zog heev (kev sib txuas lus), tab sis cov nyiaj sib khi ntawm covGraphite txheej txheejyog ntau tsis muaj zog (van der waals rog). Qhov sib txawv no hauv lub zog sib txawv ntawm lub dav hlau thiab tawm ntawm lub dav hlau, ua rau cov khoom muajaniiotropy.

2. Pyrolytic graphite tau? Saib ntawm cov txheej txheem tso nyiaj.

Kev tsim khoom ntawmPyrolytic graphitekoom nrog cov txheej txheem uas muaj kev paub txog cov tshuaj lom neegVapor DepositionCov. Yeej tseem ceeb, aHydrocarbonroj, xws li methhane (ch4), tau qhia rau hauv lub nqus tsev nqus tsev muaj asubstrateCov. Lub chamber yog ces rhuab rau heevQhov Kub Siab, feem ntau nyob rau hauv thaj tsam ntawm 2000 ° C rau 3000 ° C. Qhov no khaus dawb ua rau lubHydrocarbonroj raukev txiav txim- ib qho txheej txheem hu lipyrolysis.

Thaumpyrolysis, tusCarbon atoms los ntawm decomposed roj yog tso rau hauvsubstrateCov. Cov atoms npaj lawv tus kheej hauv ib qho kev txiav txim siab, fawm txheej txheej, sib sauPyrolytic graphiteCov. Tus nqi ntawmtso chaw, qhov kub thiab txias, thiab lub siab sab hauv lub chamber yog txhua tus tswj hwm kom cuam tshuam cov khoom kawg ntawm covPyrolytic graphiteCov. Tswj cov txheej txheem no tso cai rau tailoring cov khoom siv ceev,thermal conductivity, thiab lwm yam ntxwv.
Qhov no tuaj yeem muaj peev xwm suav nrogPyrolytic Graphite Los xij.

3. Dab tsi yog cov khoom tseem ceeb ntawm pyrolytic graphite?

TusCov khoom ntawm pyrolytic graphiteBEM ncaj qha los ntawm nws cov cim, muaj cov qauv txheej txheem fawm. Qhov no tsim qhov sib txawv tseem ceeb hauv nws tus cwj pwm nyob ntawm kev taw qhia. Nov yog qee cov yam ntxwv tseem ceeb:

• Anisotropy:Qhov no yog kab tias qhov kev txhais ntawmPyrolytic graphiteCov. Nws cov khoom yog qhov tseeb tiag tiag. Nyob rau hauv lub dav hlau ntawm txheej (hauv-dav hlau), nws ua pov thawj zoo heevthermalthiabHluav Taws Xob Kev Tshaj TawmCov. Txawm li cas los xij, nyob rau hauvKev Taw Qhia Txuasrau cov khaubncaws sab nraud povtseg, cov khoom no tau txo qis.
• Siab thermal conductivity (hauv-dav hlau): Pyrolytic graphiteBoasts Adasthermal conductivityraws lub dav hlau ntawm nws txheej, txawm tias tshaj ntawd ntawm tooj liab ntawmChav Chav Kub.
• Tsawg thermal conductivity (txiav rau dav hlau):Hauv kev sib piv, nwsthermal conductivityTxiav rau txheej txheej yog tsawg heev, ua rau nws yog ib qho tshuaj insulator zoo heev hauv cov kev taw qhia ntawd.
• DiamnoNetism: Pyrolytic graphiteyog muaj zogCuab Yeej Siv Diam, lub ntsiab lus nws cov roj hmabhlauteb. Cov cuab yeej no tseem yog aniotropic.
• Kub siab:Nws tuaj yeem tiv taus heevQhov Kub Siabhauv inert atmospheres yam tsis muaj kev cuam tshuam tseem ceeb.
• Tshuaj lom neeg inertness: Pyrolytic graphiteyog tusinert, Tiv thaiv kev tawm tsam nrog ntau yam tshuaj lom neeg.

4. Vim li cas Pyrolytic graphite lub thermal conductivity yog li zoo kawg li?

Tshwj Xeebthermal conductivity ntawm pyrolytic graphiteHauv lub dav hlau ntawm nws txheej yog vim yog cov kev txav ntawm cov suab phonons (chibrations) los ntawm kev sib khi nrujCarbon atomNetwork. Xav txog nws zoo li nthwv dej mus ncig kom sai dua los ntawm cov khoom siv, kom nruj me ntsis dua li dhau los ntawm ib qho xoob, tsis txaus ntseeg. Cov kev sib cog lus muaj zog nyob hauv lubhoobTxheej txheej muab txoj kev ntshiab rau cov kev co no mus ncig nrog tsawg kawg nkaus. Tusthermal conductivitytuaj yeem mus txog tsib zaug ntawm tooj liab.

Txawm li cas los xij, vim txoj kev sib khi ntawm covGraphite txheej txheejYog li tsis muaj zog (van der waals rog), phonons muaj teeb meem hloov chaw kub hla cov khaubncaws sab nraud povtseg. Qhov no piav qhia qhov tsawgthermal conductivitynyob rau hauv txoj kev taug. Qhov no ua rau cov khoom siv no haum rauCua Sov Dej Sov.

5. Kawm txog lub anisotropy ntawm pyrolytic graphite.

Aniiotropy, raws li tau hais ua ntej lawm, yog ib yam ntxwv tseem ceeb ntawmPyrolytic graphiteCov. Nws txhais tau tias cov khoom siv cov khoom muaj sib txawv nyob ntawm cov kev taw qhia. Qhov no yog qhov tseeb ncaj qha ntawm nws cov qauv txheej txheem. Ib tug zoo analogy yog ntoo: nws yooj yim dua rau kev sib cais ntoo raws cov nplej ntau dua hla nws.

Cov kev taw qhia no yog qhov tseem ceeb rau ntau ntawm nws cov ntawv thov. Piv txwv li, nws siabhauv-dav hlau thermal conductivityThiab txiav txiav tsawgthermal conductivityUa kom nws zoo tagnrho rau cov tshuaj tiv thaiv cua sov hauv cov khoom siv hluav taws xob, ua kom muaj zog ntawm cov khoom siv hluav taws xob thaum tiv thaiv nws los ntawm kis mus rau lwm qhov chaw. Muaj peev xwmnpuabCov khaubncaws sab nraud povtseg ntawmPyrolytic graphite, zoo ib yam liib micayog cleaved, kuj tseem los ntawm qhov noaniiotropy.

6. Dab tsi yog cov ntawv thov ntawm pyrolytic graphite?

Qhov tshwj xeebCov khoom ntawm pyrolytic graphiteUa kom haum rau ntau yam ntawm cov ntawv thov, ntau ntawm cov khoom siv uas nws anisotropic thermal thiab cov khoom siv hluav taws xob. Qee qhov tseem ceeb siv suav nrog:

• Thaum tshav kub yug thiab cua sov:HauvCov Khoom Siv Hluav Taws Xob, Pyrolytic graphiteyog siv los ua kom muaj txiaj ntsig zooThaum tshav kub kub tsimLos ntawm cov khoom sib xyaw, tiv thaiv kev kub ntxhov thiab ua kom muaj kev ntseeg siab.
• Crucibles thiab pwm:Nws qhov kev kub siab ua tsis taus thiab tshuaj lom neeg ua kom nws cov khoom tsim nyog rau cov crucibles siv nyob rau hauv high-kub metallurgical cov txheej txheem.
• Monochromators:Dav siv nyob rau hauv xoo hluav taws xob, thiab neutron monochromators.
• Daim ntaub ntawv thov biomedical:Nws biocompatibility tau coj mus rau nws siv nyob rau hauv qee yam kev mob tshuaj tiv thaiv kev kho mob.
• Aerospace Cheebtsam:Nws qhov kev ruaj khov kub thiab lub teeb yuag ua rau nws muaj txiaj ntsig hauv kev siv daim ntawv thov aerospace.
• Scanning soj ntsuam me me:Pyrolytic graphite, tshwj xeebMas qhia tau pyrolytic graphite, yog siv raws li asubstraterauTshuaj ntsuam qhov nome me (STM) vim nws lub tiaj, conductive nto. Nws tuaj yeem ua rau muaj ntau zaus.

7. Pyrolytic graphite hauv cov khoom siv hluav taws xob thiab cov soobualductors.

Nyob rau hauvCov Khoom Siv Hluav Taws XobthiabSemiconductorKev lag luam,Pyrolytic graphiteUa si lub luag haujlwm tseem ceeb hauv kev tswj hwm thermal. Niaj hnub txawb hluav taws xob tsim kom muaj cov tseem ceeb ntawm cov kub, thiab siv tau tsis txaus ntseeg yog qhov tseem ceeb rau kev ua tau zoo thiab thiav.Pyrolytic graphite'S tshwj xeebhauv-dav hlau thermal conductivityUa rau nws yog cov khoom siv zoo rau kis tau sov kom sov ntawm cov kub me, xws li cov processors thiab lub hwj chim ua kom sov.

Tsis tas li ntawd, nws qisthermal conductivityKev txiav txim siab rau lub dav hlau pab cais tawm ntawm cov cua sov, tiv thaiv nws los ntawm kev cuam tshuam rau cov khoom sib txuam ze. Tus nyias, ua rau muajPyrolytic Graphite Los xijKuj ua rau lawv haum rau siv nyob rau hauv compact cov khoom siv hluav taws xob uas qhov chaw muaj tsawg. Cov khoom siv yuav siv nyob rau hauvRoj HlawvrauLub Zog Cia.

8. Pyrolytic graphite piv rau lwm cov ntaub ntawv ntawm graphite?

Thaum txhua cov ntaub ntawv ntawm graphite qhia cov txheej txheem hexagonal cov qauv,Pyrolytic graphitesawv tawm vim nws cov kev txiav txim siab, txheej txheem txheej txheem. Qhov no muab nws cov khoom sib txawv piv rau lwm hom, zoo li:

• Ntuj Graphite:Mined los ntawm lub ntiaj teb, ntuj graphite muaj cov qauv tsawg dua liPyrolytic graphite, ua rau qis duathermalthiabHluav Taws Xob Kev Tshaj Tawm.
• GraphitelossisKhoom cuav:Qhov no feem ntau yog tsim los ntawmCarbon DubThiab ib phau ntawv, tom qab ntawd ci thiab graphitized. Nws muaj cov qauv hluav taws xob ntxiv (thaj chaw zoo sib xws hauv txhua qhov kev qhia) piv rauPyrolytic graphite.
• Graphene:ThaumPyrolytic graphiteyog tsim los ntawm stackedhoobtxheej, ib-txheejhoobmuaj haj yam ntxiv uas muaj cov khoom tshwj xeeb tshaj plaws. Txawm li cas los xij, tsim cov ntawv loj, tsis muaj kev cuam tshuam ntawmhoobTsuas yog kev sib tw.

Muab piv rau ob yam khoom no,Pyrolytic graphitestrikes qhov sib npaug ntawm kev ua tau zoo thiab kev ua lag luam, ua kom muaj kev xaiv rau ntau yam kev siv. Txheeb xyuas qhovSiab zog graphite blockNplooj ntawv.

9. Dab tsi yog cov kev txwv thiab cov nyom ntawm kev siv pyrolytic graphite?

Txawm tias nws muaj ntau yam zoo,Pyrolytic graphitePuas muaj qee qhov kev txwv:

• Brittleness:Nws tuaj yeem yog qhov sib luag thiab nquag tawg, tshwj xeeb tshaj yog nyob ntawm cov dav hlau cleavage.
• Nqi:CVD cov txheej txheem ntau lawm yuav tau kim, uaPyrolytic graphitentau tus nqi ntau dua li lwm cov ntaub ntawv ntawm graphite.
• Machinability:Thaum nws tuaj yeem raug machined, nws aniiscropic xwm tuaj yeem ua rau nws nyuaj kom ua tiav cov duab zoo thiab thev taus. TusCrystallizationthiabinomogeneitytuaj yeem cuam tshuam qhov no.
• Oxidation thaum kub siab:Txawm hais tias ruaj khov nyob rau hauv inert atmospheres,Pyrolytic graphitetuaj yeem oxidize (hnov mob nrog oxygen) ntawmkom kub siabHauv huab cua, txwv nws siv hauv qee cov ntawv thov kev kub siab uas tsis muaj kev tiv thaiv kev tiv thaiv. Yuav tsum khaws cia hauv qab no400 ° C.

10. Lub neej tom ntej ntawm Pyrolytic Graphite: Qhov kev thov tawm thiab tshawb fawb.

Kev tshawb fawb txuas ntxiv tshawb xyuas cov ntawv tshiab thiab zoo siab rauPyrolytic graphiteCov. Thaj chaw ntawm kev txaus siab muaj xws li:

• Advanced thermal tswj:Raws li cov khoom siv hluav taws xob txuas ntxiv mus rau hauv cov khoom tawg thiab ua kom muaj zog dua, qhov xav tau ntau dua ntau cov kev daws teeb meem yooj yimPyrolytic graphite-Txhua cov ntaub ntawv.
• Zog Cia:NwsHluav Taws Xob Kev Tshaj TawmThiab cov txheej txheem txheej txheem ua rau nws muaj peev xwm sib tw rau kev siv hauv cov roj teeb siab thiab cov supercapacitors. Cov khoom yogTshuaj inert.
• Sensors:Nws cov khoom tshwj xeeb tau raug tshuaj xyuas rau kev siv ntau hom kev xav.
• Biomedical Engineering:Kev tshawb fawb ntxiv rau hauv nws biocompatibility yuav ua rau cov ntawv thov tshiab hauv cov khoom siv kho mob thiab cov pob txha.
  * Kev tshawb fawb ntawm cov lwg me meCov kws tshawb fawb saum npoo siv Hopg uas yog substrate uas yuav kawm ntau yam ntawmAlolulatic MoleculesCov. Hopg muab ib qhoRaug ntxuav kom huv sitxawm tias tom qab tshuav nyob rau hauvCua rau teevCov. Lub substrate tuaj yeemTswj cov molecules ** thiab muab lub dav hlau zoo.
• Nanostructuure: Tusnanostructuuretau pom los qhiasemiconductingkev coj cwj pwm.

Tseem ceeb takaways: pyrolytic graphite qhov tseem ceeb

• Pyrolytic graphiteyog ib daim ntawv tshwj xeeb ntawm graphite nrog ib qho kev txiav txim siab, fawm txheej txheej.
• Nws ua rau pom tshwj xeebaniiotropy, nrog siabthermalthiabHluav Taws Xob Kev Tshaj TawmHauv lub dav hlau ntawm txheej thiab tsawg kev coj ua ncaj qha rau lub dav hlau.
• Nws yog tsim los ntawm kev siv tshuaj lom neegtso chaw (pyrolysis), tus txheej txheem uas tso cai rau kev tswj hwm nws cov khoom.
• Cov ntawv thov tseem ceeb muaj xws li kub cov neeg tuaj yeem, cov ntoo khaub thuas, ib qho kev sib xyaw ua ke, thiab substrates rau metercopy.
• Nws yog cov khoom siv muaj txiaj ntsig hauvCov Khoom Siv Hluav Taws Xobthiab semiconductors rau kev tswj hwm thermal.
• Thaum ntau kim dua li lwm cov ntaub ntawv ntawm graphite, nws cov khoom tshwj xeeb uas tiv thaiv nws siv hauv kev thov cov ntawv thov.
• Kev tshawb fawb txuas ntxiv yog tshawb txog cov ntawv thov tshiab hauv kev cia khoom siv hluav taws xob, cov sensors, thiab biomedical engineering.
• Nco ntsoov tshawb pebMuaj Siab Purity 99.9% Graphite hmoovthiabKub kub tiv taus graphite crucible rau meltingCov nplooj ntawv khoom.
• Xav txog peb rau kojkhoom siv hluav taws xobxav tau.
  Graphite's DelocalizedΠ Txheej Systemdhau lubDaim Ntawv Graphene Cov Ntawvyog lub luag haujlwm rau hluav taws xobconductivity thiab thermalruaj khov.
• Nws yog ib qho tseem ceeb kom nkag siab txogDelocalized π-sib khinruab nrab ntawm cov ntawv txheebkom txiav txim siab yuav khoom.