Silica (SiO2 ) plays lub luag haujlwm tseem ceeb thiab tseem ceeb hauvE-iav, tsim lub bedrock rau tag nrho nws cov khoom zoo heev. Cias muab, silica yog "network qub" lossis "skeleton" ntawm E-iav. Nws txoj haujlwm tuaj yeem raug cais tshwj xeeb rau hauv cov hauv qab no:
1. Tsim cov iav Network Structure (Core Function)
Qhov no yog qhov tseem ceeb tshaj plaws ntawm silica. Silica yog iav-forming oxide nws tus kheej. Nws SiO4 tetrahedra txuas rau ib leeg los ntawm kev sib txuas cov pa oxygen atoms, tsim kom muaj kev sib txuas ntxiv, muaj zog, thiab random peb-dimensional network qauv.
- Analogy:Qhov no zoo li cov pob txha steel ntawm lub tsev nyob hauv kev tsim kho. Silica muab lub hauv paus ntsiab lus rau tag nrho cov iav qauv, thaum lwm yam khoom (xws li calcium oxide, aluminium oxide, boron oxide, thiab lwm yam) yog cov ntaub ntawv uas sau los yog hloov cov pob txha no los kho cov kev ua tau zoo.
- Yog tsis muaj cov pob txha silica no, cov khoom siv khov kho hauv lub xeev tsis tuaj yeem tsim.
2. Kev muab hluav taws xob rwb thaiv tsev zoo heev
- High Electrical Resistivity:Silica nws tus kheej muaj qhov tsis tshua muaj ion txav mus los, thiab cov khoom siv tshuaj lom neeg (Si-O daim ntawv cog lus) ruaj khov thiab muaj zog, ua rau nws nyuaj rau ionize. Lub network txuas ntxiv nws tsim tau zoo heev txwv tsis pub txav ntawm cov nqi hluav taws xob, muab E-iav ntim siab heev thiab tiv thaiv qhov chaw.
- Tsawg Dielectric Constant thiab Tsawg Dielectric poob:E-iav cov khoom dielectric yog qhov ruaj khov ntawm cov khoom siv siab thiab kub siab. Qhov no feem ntau yog vim qhov sib luag thiab ruaj khov ntawm SiO2 lub network qauv, uas ua rau muaj qhov qis ntawm polarization thiab tsawg zog poob (hloov mus rau cua sov) hauv qhov hluav taws xob ntau zaus. Qhov no ua rau nws zoo tagnrho rau siv los ua cov khoom siv txhawb zog hauv hluav taws xob Circuit Court boards (PCBs) thiab high-voltage insulators.
3. Ua kom muaj tshuaj lom neeg ruaj khov
E-iav ua pov thawj zoo heev rau dej, acids (tshwj tsis yog hydrofluoric thiab kub phosphoric acid), thiab tshuaj.
- Inert Nto:Qhov ntom ntom Si-O-Si network muaj cov tshuaj lom neeg tsawg heev thiab tsis yooj yim rau cov dej los yog H + ions. Yog li ntawd, nws cov hydrolysis tsis kam thiab acid kuj zoo heev. Qhov no ua kom ntseeg tau tias cov ntaub ntawv sib xyaw ntxiv los ntawm E-iav fiber ntau tswj lawv cov kev ua tau zoo nyob rau lub sijhawm ntev, txawm tias nyob rau hauv ib puag ncig hnyav.
4. Kev pab cuam rau kev siv tshuab siab
Txawm tias lub zog kawg ntawmiav fibersNws kuj tseem cuam tshuam los ntawm cov yam ntxwv xws li qhov tsis xws luag thiab micro-cracks, lawv lub zog theoretical feem ntau yog los ntawm Si-O covalent bonds muaj zog thiab peb-seem network qauv.
- High Bond Zog:Lub zog daim ntawv cog lus ntawm Si-O daim ntawv cog lus yog siab heev, uas ua rau cov iav pob txha nws tus kheej muaj zog heev, muab cov fiber ntau nrog lub zog tensile siab thiab elastic modulus.
5. Muab cov khoom cua sov zoo tshaj plaws
- Tsawg Thermal Expansion Coefficient:Silica nws tus kheej muaj tsawg coefficient ntawm thermal expansion. Vim tias nws ua haujlwm raws li lub cev pob txha loj, E-iav kuj muaj qhov sib txawv thermal expansion coefficient. Qhov no txhais tau hais tias nws muaj qhov zoo ntawm qhov ruaj khov thaum lub sijhawm hloov pauv kub thiab tsis tshua muaj peev xwm ua kom muaj kev ntxhov siab ntau dhau vim thermal expansion thiab contraction.
- High Softening Point:Silica lub melting point yog siab heev (kwv yees li 1723∘C). Txawm hais tias qhov sib ntxiv ntawm lwm cov fluxing oxides txo qis qhov kawg melting kub ntawm E-iav, nws cov SiO2 core tseem ua kom cov iav muaj qhov muag txaus siab thiab thermal stability kom tau raws li qhov yuav tsum tau ua ntawm feem ntau cov ntawv thov.
Hauv ib txwmE-iavmuaj pes tsawg leeg, cov ntsiab lus silica feem ntau yog 52% -56% (los ntawm qhov hnyav), ua rau nws yog ib qho loj tshaj plaws oxide tivthaiv. Nws txhais cov yam ntxwv tseem ceeb ntawm cov iav.
Division of Labor ntawm Oxides hauv E-iav:
- SiO 2(Silica): Lub cev pob txha; muab cov qauv kev ruaj ntseg, hluav taws xob rwb thaiv tsev, tshuaj lom neeg ruaj khov, thiab lub zog.
- Al2O3(Alumina): Pab network qub thiab stabilizer; tsub kom tshuaj stability, mechanical zog, thiab txo devitrification nyiam.
- B2O3(Boron Oxide): Flux thiab khoom modifier; txo qhov kub ntawm melting (lub zog txuag) thaum txhim kho thermal thiab hluav taws xob zog.
- CaO/MgO(Calcium Oxide / Magnesium Oxide): Flux thiab stabilizer; pab nyob rau hauv melting thiab kho chemical durability thiab devitrification zog.
Post lub sij hawm: Oct-10-2025
