Cov khoom siv silicon carbide porcelain uas muaj cov tshuaj reaction-sintered muaj lub zog compressive zoo ntawm qhov kub thiab txias, tiv taus cua sov rau huab cua oxidation, tiv taus hnav zoo, tiv taus kub zoo, coefficient me me ntawm linear expansion, coefficient hloov cua sov siab, hardness siab, tiv taus kub thiab kev puas tsuaj, tiv thaiv hluav taws thiab lwm yam zoo. Siv dav hauv tsheb, tshuab automation, kev tiv thaiv ib puag ncig ecological, aerospace engineering, cov ntaub ntawv cov ntsiab lus hluav taws xob, lub zog fais fab thiab lwm yam teb, tau dhau los ua cov khoom siv ceramics pheej yig thiab tsis muaj qhov hloov pauv hauv ntau qhov chaw lag luam.
Kev sintering tsis muaj siab yog hu ua txoj kev calcination SiC zoo. Rau cov tshuab casting txuas ntxiv sib txawv, kev sintering tsis muaj nias tuaj yeem faib ua cov khoom siv calcination thiab cov kua ua haujlwm siab calcination. Los ntawm kev ntxiv B thiab C (cov pa oxygen tsawg dua 2%) ua ke hauv cov hmoov Beta SiC zoo heev, S. Proehazka raug sintered rau hauv lub cev SIC calcined nrog qhov ceev ntawm ntau dua 98% ntawm xyoo 2020, nrog Al2O3 thiab Y2O3 ua cov khoom ntxiv. Calcined 0.5m-SiC hauv qab 1850-1950 (qhov chaw me me nrog me ntsis SiO2), qhov xaus lus yog tias qhov ceev ntawm SiC porcelain tshaj 95% ntawm qhov ceev theoretical yooj yim, qhov loj me ntawm cov noob yog me me, thiab qhov nruab nrab loj, uas yog 1.5μm.
Reactive sintering silicon carbide yog hais txog tag nrho cov txheej txheem ntawm kev cuam tshuam cov qauv porous billet nrog cov kua theem lossis cov kua theem siab, txhim kho qhov zoo ntawm billet, txo qhov qhov cua, thiab calcining cov khoom tiav nrog qee lub zog thiab qhov tseeb. Plutonium-sic hmoov thiab siab purity graphite yog sib xyaw hauv qee qhov sib piv thiab cua sov rau txog 1650 los tsim cov plaub hau embryo. Tib lub sijhawm, nws nkag mus lossis nkag mus rau hauv cov hlau los ntawm cov kua theem Si, cuam tshuam nrog silicon carbide los tsim plutonium-sic, thiab fuses nrog cov plutonium-sic uas twb muaj lawm. Tom qab Si infiltration, lub cev sintered tshuaj tiv thaiv nrog cov ntsiab lus sib piv thiab qhov loj me tsis tau ntim tuaj yeem tau txais. Piv nrog rau lwm txoj kev sintering, nyob rau hauv cov txheej txheem ntawm cov khoom siv sintering siab, qhov loj me hloov pauv yog me me, tuaj yeem tsim qhov loj me ntawm cov khoom, tab sis muaj ntau SiC ntawm lub cev calcined, cov yam ntxwv kub siab ntawm cov tshuaj tiv thaiv sintered SiC porcelain yuav phem dua. Cov khoom siv SiC uas tsis muaj zog calcined, cov khoom siv SiC kub isostatic calcined thiab cov khoom siv SiC uas muaj tshuaj sintered muaj cov yam ntxwv sib txawv.
Cov chaw tsim khoom siv silicon carbide sintering: Piv txwv li, SiC porcelain ntawm qib calcined relative density thiab bending strength, kub nias sintering thiab kub isostatic nias calcination ntau dua, thiab reactive sintering SiC yog qhov tsawg. Tib lub sijhawm, cov khoom siv lub cev ntawm SiC porcelain hloov pauv nrog kev hloov pauv ntawm calcination modifier. Lub non-pressure sintering, kub nias sintering thiab reaction sintering ntawm SiC porcelain muaj kev tiv thaiv alkaline zoo thiab acid tsis kam, tab sis cov tshuaj tiv thaiv sintered SiC porcelain muaj kev tiv thaiv tsis muaj zog rau HF thiab lwm yam acid corrosion muaj zog heev. Thaum qhov kub thiab txias tsawg dua 900, lub zog khoov ntawm feem ntau SiC porcelain siab dua li ntawm qhov kub siab sintered porcelain, thiab lub zog khoov ntawm reactive sintered SiC porcelain poob qis thaum nws tshaj 1400. (Qhov no yog tshwm sim los ntawm qhov poob qis ntawm lub zog khoov ntawm qee qhov ntawm laminated iav Si dhau qhov kub thiab txias hauv lub cev calcined. Kev ua haujlwm kub siab ntawm SiC ceramics sintered tsis muaj siab calcination thiab nyob rau hauv kub tas li static siab feem ntau cuam tshuam los ntawm cov hom additives.
Lub sijhawm tshaj tawm: Kaum Ib Hlis-07-2023