Cov ceramics tshwj xeeb yog hais txog cov chav kawm ntawm ceramics nrog cov khoom siv tshwj xeeb, lub cev lossis tshuaj lom neeg, cov khoom siv raw siv thiab cov cuab yeej tsim khoom yuav tsum tau sib txawv ntawm cov ceramics zoo tib yam thiab kev loj hlob. Raws li cov yam ntxwv thiab kev siv, tshwj xeeb ceramics tuaj yeem muab faib ua ob pawg: cov qauv ceramics thiab cov khoom siv ceramics. Ntawm lawv, cov txheej txheem ceramics xa mus rau ceramics uas tuaj yeem siv los ua cov khoom siv engineering, uas feem ntau muaj lub zog siab, siab hardness, siab elastic modulus, kub tsis kam, hnav tsis kam, corrosion kuj, oxidation tsis kam, thermal shock thiab lwm yam ntxwv.
Muaj ntau ntau hom qauv ceramics, qhov zoo thiab qhov tsis zoo, thiab daim ntawv thov kev taw qhia ntawm qhov zoo thiab qhov tsis zoo yog qhov sib txawv, ntawm cov "silicon nitride ceramics" vim tias qhov sib npaug ntawm kev ua tau zoo hauv txhua yam, yog lub npe hu ua qhov kev ua tau zoo tshaj plaws hauv cov tsev neeg ceramics, thiab muaj ntau yam kev siv ntau yam.
Qhov zoo ntawm silicon nitride ceramics
Silicon nitride (Si3N4) tuaj yeem muab faib ua covalent daim ntawv cog lus, nrog [SiN4] 4-tetrahedron ua chav tsev. Cov haujlwm tshwj xeeb ntawm nitrogen thiab silicon atoms tuaj yeem pom los ntawm daim duab hauv qab no, silicon nyob hauv nruab nrab ntawm tetrahedron, thiab cov haujlwm ntawm plaub qhov ntawm tetrahedron yog nyob ntawm nitrogen atoms, thiab tom qab ntawd txhua txhua peb tetrahedron sib koom ib lub atom, tas li. ncua nyob rau hauv peb-dimensional qhov chaw. Thaum kawg, lub network qauv tsim. Ntau yam khoom ntawm silicon nitride muaj feem xyuam rau cov qauv tetrahedral no.
Muaj peb cov qauv crystalline ntawm silicon nitride, uas yog α, β thiab γ theem, ntawm uas α thiab β theem yog cov feem ntau cov ntaub ntawv ntawm silicon nitride. Vim hais tias cov nitrogen atoms tau ruaj khov ua ke, silicon nitride muaj lub zog zoo, siab hardness thiab kub tsis kam, thiab hardness tuaj yeem ncav cuag HRA91 ~ 93; Zoo thermal rigidity, tuaj yeem tiv taus qhov kub ntawm 1300 ~ 1400 ℃; Cov tshuaj tiv thaiv me me nrog cov pa roj carbon thiab hlau ua rau muaj kev sib txhuam coefficient tsawg; Nws yog tus kheej-lubricating thiab yog li tiv taus hnav; Corrosion kuj muaj zog, ntxiv rau hydrofluoric acid, nws tsis hnov mob nrog lwm cov inorganic acids, kub kub kuj muaj oxidation kuj; Nws kuj muaj qhov zoo thermal shock tsis kam, ntse txias nyob rau hauv cov huab cua thiab ces ntse cua sov yuav tsis crumble; Lub creep ntawm silicon nitride ceramics txo qis ntawm qhov kub thiab txias, thiab cov yas deformation qeeb me me nyob rau hauv qhov kev txiav txim siab kub thiab ruaj khov.
Tsis tas li ntawd, silicon nitride ceramics kuj muaj lub zog tshwj xeeb, hom tshwj xeeb, siab thermal conductivity, cov khoom siv hluav taws xob zoo thiab lwm yam zoo, yog li nws muaj cov txiaj ntsig tshwj xeeb hauv qhov chaw huab cua xws li kub, kub ceev, muaj zog corrosive media, thiab yog suav tias yog ib qho kev cog lus zoo tshaj plaws ntawm cov khoom siv ceramic rau kev txhim kho thiab kev siv, thiab feem ntau yog thawj qhov kev xaiv hauv ntau daim ntawv thov uas yuav tsum tau sim.
Post lub sij hawm: Aug-15-2023