Qhia txog cov khoom tshwj xeeb thiab kev siv cov hmoov silicon carbide ntsuab
Hauv cov khoom siv thev naus laus zis siab niaj hnub no, cov hmoov silicon carbide ntsuab maj mam dhau los ua qhov tseem ceeb hauv zej zog kev tshawb fawb txog cov ntaub ntawv nrog nws cov khoom siv lub cev thiab tshuaj lom neeg tshwj xeeb. Cov khoom sib xyaw no muaj cov pa roj carbon thiab silicon tau pom tias muaj kev siv dav hauv ntau qhov chaw lag luam vim nws cov qauv siv lead ua tshwj xeeb thiab kev ua tau zoo heev. Tsab xov xwm no yuav tshawb nrhiav tob txog cov khoom tshwj xeeb ntawm cov hmoov silicon carbide ntsuab thiab nws cov peev xwm siv hauv ntau qhov chaw.
1. Cov yam ntxwv tseem ceeb ntawm cov hmoov silicon carbide ntsuab
Cov silicon carbide ntsuab (SiC) yog cov khoom siv hluavtaws superhard thiab yog cov khoom sib txuas covalent. Nws cov qauv siv lead ua rau muaj lub kaw lus hexagonal nrog kev npaj zoo li pob zeb diamond. Cov hmoov silicon carbide ntsuab feem ntau yog hais txog cov khoom hmoov nrog qhov loj me ntawm 0.1-100 microns, thiab nws cov xim muaj ntau yam xim los ntawm lub teeb ntsuab mus rau ntsuab tsaus vim muaj qhov sib txawv ntawm qhov huv thiab cov ntsiab lus tsis huv.
Los ntawm cov qauv me me, txhua lub silicon atom hauv cov xim ntsuab silicon carbide tsim cov kev sib koom ua ke tetrahedral nrog plaub lub carbon atoms. Cov qauv sib txuas no muaj zog ua rau cov khoom siv muaj zog heev thiab ruaj khov tshuaj lom neeg. Nws tsim nyog sau cia tias Mohs hardness ntawm ntsuab silicon carbide ncav cuag 9.2-9.3, thib ob tsuas yog pob zeb diamond thiab cubic boron nitride, uas ua rau nws tsis tuaj yeem hloov pauv hauv thaj chaw ntawm abrasives.
2. Cov khoom tshwj xeeb ntawm cov hmoov silicon carbide ntsuab
1. Cov khoom siv kho tshuab zoo heev
Qhov tshwj xeeb tshaj plaws ntawm cov hmoov silicon carbide ntsuab yog nws qhov nyuaj heev. Nws qhov Vickers hardness tuaj yeem ncav cuag 2800-3300kg / mm², uas ua rau nws ua tau zoo thaum ua cov khoom siv tawv. Tib lub sijhawm, cov silicon carbide ntsuab kuj muaj lub zog compressive zoo thiab tseem tuaj yeem tswj tau lub zog kho tshuab siab ntawm qhov kub siab. Qhov no ua rau nws siv tau rau hauv qhov chaw ib puag ncig hnyav.
2. Cov khoom siv thermal zoo heev
Qhov thermal conductivity ntawm ntsuab silicon carbide yog siab txog li 120-200W / (m · K), uas yog 3-5 npaug ntawm cov hlau ib txwm. Qhov thermal conductivity zoo heev no ua rau nws yog cov khoom siv zoo tshaj plaws rau kev tso cua sov. Qhov zoo tshaj plaws yog tias qhov coefficient thermal expansion ntawm ntsuab silicon carbide tsuas yog 4.0 × 10⁻⁶ / ℃, uas txhais tau tias nws muaj kev ruaj khov zoo heev thaum qhov kub hloov pauv, thiab yuav tsis tsim cov deformation pom tseeb vim yog thermal expansion thiab contraction.
3. Kev ruaj khov tshuaj zoo heev
Hais txog cov khoom siv tshuaj lom neeg, cov silicon carbide ntsuab muaj zog heev. Nws tuaj yeem tiv taus kev xeb ntawm feem ntau cov kua qaub, alkalis thiab cov tshuaj ntsev, thiab tseem tuaj yeem ruaj khov txawm tias nyob rau hauv qhov kub siab. Kev sim qhia tau hais tias cov silicon carbide ntsuab tseem tuaj yeem tswj tau qhov ruaj khov zoo hauv qhov chaw oxidizing qis dua 1000 ℃, uas ua rau nws muaj peev xwm siv tau ntev hauv qhov chaw corrosive.
4. Cov khoom siv hluav taws xob tshwj xeeb
Cov silicon carbide ntsuab yog cov khoom siv semiconductor dav dav nrog qhov dav ntawm bandgap ntawm 3.0 eV, uas loj dua li 1.1 eV ntawm silicon. Qhov no ua rau nws tuaj yeem tiv taus cov hluav taws xob siab dua thiab kub dua, thiab muaj cov txiaj ntsig tshwj xeeb hauv kev siv hluav taws xob fais fab. Tsis tas li ntawd, cov silicon carbide ntsuab kuj muaj kev txav mus los ntawm hluav taws xob siab, uas ua rau nws muaj peev xwm tsim cov khoom siv zaus siab.
3. Kev npaj cov txheej txheem ntawm cov hmoov silicon carbide ntsuab
Kev npaj cov hmoov silicon carbide ntsuab feem ntau siv cov txheej txheem Acheson. Txoj kev no sib tov cov xuab zeb quartz thiab roj av coke hauv ib qho piv txwv thiab ua kom sov rau 2000-2500 ℃ hauv lub cub tawg kom ua rau muaj kev sib xyaw. Cov silicon carbide ntsuab uas tsim los ntawm kev sib xyaw ua ke yuav raug zom, ntsuas, thiab pickling kom tau txais cov khoom me me ntawm ntau qhov loj me.
Nyob rau xyoo tas los no, nrog rau kev nce qib ntawm thev naus laus zis, qee txoj kev npaj tshiab tau tshwm sim. Chemical vapor deposition (CVD) tuaj yeem npaj cov hmoov silicon carbide ntsuab uas muaj qhov huv siab nano-scale; txoj kev sol-gel tuaj yeem tswj tau qhov loj me thiab morphology ntawm cov hmoov; txoj kev plasma tuaj yeem ua tiav kev tsim khoom tas mus li thiab txhim kho kev ua haujlwm zoo. Cov txheej txheem tshiab no muab ntau txoj hauv kev rau kev ua kom zoo dua qub thiab kev nthuav dav ntawm cov hmoov silicon carbide ntsuab.
4. Cov chaw siv tseem ceeb ntawm cov hmoov silicon carbide ntsuab
1. Kev sib tsoo thiab polishing precision
Ua ib qho abrasive superhard, ntsuab silicon carbide micropowder yog siv dav hauv kev ua cov cemented carbide, ceramics, iav thiab lwm yam khoom siv. Hauv kev lag luam semiconductor, cov hmoov ntsuab silicon carbide purity siab yog siv rau polishing silicon wafers, thiab nws cov kev ua tau zoo dua li cov alumina abrasives ib txwm muaj. Hauv kev ua cov khoom siv kho qhov muag, ntsuab silicon carbide hmoov tuaj yeem ua tiav nano-scale surface roughness thiab ua tau raws li cov kev xav tau ua tiav ntawm cov khoom siv kho qhov muag siab.
2. Cov ntaub ntawv ceramic siab heev
Hmoov silicon carbide ntsuab yog ib qho khoom siv tseem ceeb rau kev npaj cov khoom siv ceramics ua tau zoo. Cov khoom siv ceramics uas muaj cov khoom siv kho tshuab zoo heev thiab thermal stability tuaj yeem ua los ntawm kev nias kub sintering lossis cov txheej txheem sintering. Hom khoom siv ceramic no yog siv dav hauv cov khoom tseem ceeb xws li cov foob pob hluav taws xob, cov kabmob, thiab cov nozzles, tshwj xeeb tshaj yog nyob rau hauv cov xwm txheej ua haujlwm hnyav xws li kub thiab xeb.
3. Cov khoom siv hluav taws xob thiab cov khoom siv semiconductor
Hauv kev lag luam hluav taws xob, cov hmoov silicon carbide ntsuab yog siv los npaj cov ntaub ntawv semiconductor dav dav. Cov khoom siv fais fab raws li cov silicon carbide ntsuab muaj cov yam ntxwv ua haujlwm siab, siab voltage, thiab kub siab, thiab qhia txog lub peev xwm zoo hauv cov tsheb fais fab tshiab, cov ntse grids thiab lwm yam teb. Cov kev tshawb fawb tau qhia tias cov khoom siv fais fab silicon carbide ntsuab tuaj yeem txo qhov poob zog ntau dua 50% piv rau cov khoom siv silicon ib txwm muaj.
4. Kev txhawb zog sib xyaw
Ntxiv cov hmoov silicon carbide ntsuab ua ib theem txhawb zog rau cov hlau lossis polymer matrix tuaj yeem txhim kho lub zog, qhov nyuaj thiab kev hnav tsis kam ntawm cov khoom sib xyaw. Hauv kev lag luam aerospace, cov khoom sib xyaw ua los ntawm txhuas-raws li silicon carbide yog siv los tsim cov khoom sib xyaw ua ke uas sib dua thiab muaj zog; hauv kev lag luam tsheb, cov ntaub nres silicon carbide txhawb nqa qhia tau tias muaj kev tiv thaiv kub zoo heev.
5. Cov ntaub ntawv refractory thiab coatings
Siv qhov ruaj khov ntawm cov silicon carbide ntsuab hauv qhov kub thiab txias, cov khoom siv refractory ua tau zoo tuaj yeem npaj tau. Hauv kev lag luam smelting hlau, cov cib refractory silicon carbide siv dav hauv cov khoom siv kub xws li lub cub tawg thiab cov hloov pauv. Tsis tas li ntawd, cov txheej txheem silicon carbide tuaj yeem muab kev tiv thaiv zoo heev rau kev hnav thiab xeb rau cov khoom siv hauv paus, thiab siv rau hauv cov khoom siv tshuaj lom neeg, cov hniav turbine thiab lwm yam teb.