Daim ntawv thov ntawm α-alumina hauv cov khoom tshiabalumina ceramics
Txawm hais tias muaj ntau hom khoom siv ceramic tshiab, lawv tuaj yeem muab faib ua peb pawg raws li lawv cov haujlwm thiab kev siv: cov khoom siv ceramic ua haujlwm (tseem hu ua cov khoom siv ceramic hluav taws xob), cov khoom siv ceramic ua qauv (tseem hu ua cov khoom siv ceramic engineering) thiab cov khoom siv bioceramics. Raws li cov khoom siv raw sib txawv siv, lawv tuaj yeem muab faib ua cov khoom siv ceramic oxide, cov khoom siv ceramic nitride, cov khoom siv ceramic boride, cov khoom siv ceramic carbide thiab cov khoom siv ceramic hlau. Ntawm lawv, alumina ceramics tseem ceeb heev, thiab nws cov khoom siv raw yog α-alumina hmoov ntawm ntau yam kev qhia.
α-alumina yog siv dav hauv kev tsim ntau yam khoom siv ceramic tshiab vim nws lub zog siab, siab tawv, kub tsis kam, hnav tsis kam thiab lwm yam khoom zoo heev. Nws tsis yog tsuas yog cov khoom siv hmoov rau cov khoom siv alumina ceramics xws li cov khoom siv sib xyaw ua ke, cov pob zeb cuav, cov cuab yeej txiav, cov pob txha cuav, thiab lwm yam, tab sis kuj siv tau ua tus nqa phosphor, cov khoom siv refractory siab heev, cov khoom siv sib tsoo tshwj xeeb, thiab lwm yam. Nrog rau kev txhim kho ntawm kev tshawb fawb thiab thev naus laus zis niaj hnub, daim ntawv thov ntawm α-alumina tau nthuav dav sai, thiab qhov kev thov ntawm kev ua lag luam kuj nce ntxiv, thiab nws cov kev cia siab dav heev.
Daim ntawv thov ntawm α-alumina hauv cov khoom siv ceramics
Cov khoom siv ua los ntawm cov av nplaumXa mus rau cov khoom siv ceramics siab heev uas siv lawv cov khoom siv hluav taws xob, sib nqus, suab, kho qhov muag, thermal thiab lwm yam khoom lossis lawv cov teebmeem sib txuas kom ua tiav qee yam haujlwm. Lawv muaj ntau yam khoom siv hluav taws xob xws li rwb thaiv tsev, dielectric, piezoelectric, thermoelectric, semiconductor, ion conductivity thiab superconductivity, yog li lawv muaj ntau yam haujlwm thiab kev siv dav heev. Tam sim no, cov khoom tseem ceeb uas tau muab tso rau hauv kev siv tiag tiag ntawm qhov loj yog insulating ceramics rau cov khoom siv sib xyaw ua ke thiab ntim khoom, automotive spark plug insulating ceramics, capacitor dielectric ceramics siv dav hauv TV thiab video recorders, piezoelectric ceramics nrog ntau yam kev siv thiab cov khoom siv rhiab heev rau ntau yam sensors. Tsis tas li ntawd, lawv kuj siv rau cov raj teeb pom kev zoo sodium siab.
1. Cov khoom siv hluav taws xob rwb thaiv tsev
Cov khoom siv hluav taws xob rwb thaiv tsev uas siv hluav taws xob los ua lub txim hluav taws xob tam sim no yog tib qho kev siv loj tshaj plaws ntawm cov khoom siv hluav taws xob hauv lub cav. Vim tias alumina muaj kev rwb thaiv hluav taws xob zoo heev, muaj zog heev, tiv taus siab thiab tiv taus thermal shock, cov khoom siv hluav taws xob rwb thaiv tsev uas siv hluav taws xob rwb thaiv tsev alumina tau siv dav hauv ntiaj teb. Cov kev cai rau α-alumina rau cov khoom siv hluav taws xob yog cov hmoov me me uas muaj sodium tsawg, uas cov ntsiab lus sodium oxide yog ≤0.05% thiab qhov nruab nrab ntawm cov khoom me me yog 325 mesh.
2. Cov khoom siv sib xyaw ua ke thiab cov ntaub ntawv ntim khoom
Cov khoom siv ua los ntawm cov khoom siv av nplaum thiab cov khoom ntim khoom zoo dua li cov yas hauv cov hauv qab no: kev tiv thaiv rwb thaiv tsev siab, kev tiv thaiv tshuaj lom neeg corrosion siab, kev sib khi siab, kev tiv thaiv dej nkag mus, tsis muaj kev cuam tshuam, thiab tsis muaj kuab paug rau ultra-pure semiconductor silicon. Cov yam ntxwv ntawm α-alumina xav tau rau cov khoom siv hluav taws xob sib xyaw thiab cov khoom ntim khoom yog: coefficient nthuav dav thermal 7.0 × 10-6 / ℃, thermal conductivity 20-30W / K · m (chav sov), dielectric tas mus li 9-12 (IMZH), dielectric poob 3 ~ 10-4 (IMZH), ntim resistivity> 1012-1014Ω · cm (chav sov).
Nrog rau kev ua tau zoo thiab kev sib koom ua ke ntawm cov integrated circuits, cov kev cai nruj dua tau muab tso rau pem hauv ntej rau cov substrates thiab cov ntaub ntawv ntim khoom:
Raws li lub cua sov ntawm lub chip nce ntxiv, yuav tsum muaj cov thermal conductivity siab dua.
Nrog rau qhov ceev ceev ntawm lub computer, qhov dielectric tsis tu ncua qis yog qhov yuav tsum tau muaj.
Tus coefficient ntawm thermal expansion yuav tsum ze rau silicon. Qhov no ua rau muaj qhov xav tau ntau dua rau α-alumina, uas yog, nws tsim tawm hauv kev coj ntawm kev ntshiab thiab zoo.
3. Lub teeb ci ntsa iab siab
Cov khoom siv av nplaum zooUa los ntawm cov khoom siv alumina uas muaj cov khoom siv zoo heev, muaj cov yam ntxwv ntawm kev tiv taus kub, tiv taus corrosion, rwb thaiv tsev zoo, muaj zog, thiab lwm yam, thiab yog cov khoom siv ceramic zoo heev. Cov pob tshab polycrystalline ua los ntawm cov khoom siv alumina uas muaj cov khoom siv zoo heev nrog me ntsis magnesium oxide, iridium oxide lossis iridium oxide additives, thiab ua los ntawm huab cua sintering thiab kub nias sintering, tuaj yeem tiv taus qhov corrosion ntawm cov pa sodium kub thiab siv tau ua cov teeb pom kev zoo sodium siab nrog kev ua haujlwm siab.
Daim ntawv thov ntawm α-alumina hauv cov qauv ceramics
Raws li cov ntaub ntawv inorganic biomedical, cov ntaub ntawv bioceramic tsis muaj cov teebmeem lom piv rau cov ntaub ntawv hlau thiab cov ntaub ntawv polymer, thiab muaj kev sib raug zoo biocompatibility thiab corrosion tsis kam nrog cov ntaub so ntswg biological. Lawv tau raug suav tias yog qhov tseem ceeb los ntawm tib neeg. Kev tshawb fawb thiab kev siv tshuaj kho mob ntawm cov ntaub ntawv bioceramic tau tsim los ntawm kev hloov pauv luv luv thiab kev sau mus rau kev cog ruaj khov thiab ruaj khov, thiab los ntawm cov ntaub ntawv inert biological mus rau cov ntaub ntawv biologically active thiab cov ntaub ntawv sib xyaw ntau theem.
Nyob rau hauv xyoo tas los no, porousalumina ceramicstau siv los ua cov pob txha cuav, cov pob txha cuav hauv caug, cov taub hau cuav femoral, lwm cov pob txha cuav, cov hauv paus hniav cuav, cov ntsia hlau kho pob txha, thiab kev kho lub qhov muag vim lawv cov tshuaj tiv thaiv corrosion, hnav tsis kam, zoo kub ruaj khov, thiab thermoelectric khoom. Txoj kev rau kev tswj qhov loj me ntawm lub qhov thaum lub sijhawm npaj cov porous alumina ceramics yog sib tov alumina cov khoom sib txawv ntawm cov khoom sib txawv, ua npuas ncauj impregnate, thiab tsuag kom qhuav cov khoom. Cov phaj txhuas kuj tseem tuaj yeem anodized los tsim cov qhov me me nano-scale microporous channel-type.