Generalkev piav qhia ntawmCov tshuaj tiv thaivBonded SiC
Cov tshuaj tiv thaiv Bonded SiC muaj cov khoom siv kho tshuab thiab oxidation tsis kam. Nws tus nqi kuj tsawg. Nyob rau hauv lub neej tam sim no, nws tau attracted ntau thiab ntau xav nyob rau hauv ntau yam lag luam.
SiC yog daim ntawv cog lus muaj zog heev. Hauv sintering, tus nqi diffusion yog tsawg heev. Nyob rau tib lub sijhawm, qhov saum npoo ntawm cov khoom feem ntau npog cov txheej txheej oxide nyias uas ua lub luag haujlwm ntawm qhov cuam tshuam ntawm qhov sib txawv. Ntshiab SiC tsis yog sintered thiab compact tsis muaj sintering additives. Txawm hais tias siv cov txheej txheem kub-nias, nws yuav tsum tau xaiv cov khoom tsim nyog. Tsuas yog nyob rau ntawm qhov kub thiab txias heev, cov ntaub ntawv tsim nyog rau engineering density ze rau theoretical ntom yuav tsum nyob rau hauv thaj tsam ntawm 1950 ℃ to 2200 ℃ .Tam sim no, nws cov duab thiab loj yuav raug txwv. Txawm hais tias SIC composites tuaj yeem tau los ntawm vapor deposition, nws yog txwv rau kev npaj cov ntaub ntawv tsis tshua muaj ntom lossis nyias txheej. Vim nws lub sijhawm nyob ntsiag to ntev, tus nqi tsim khoom yuav nce ntxiv.
Reaction Bonded SiC tau tsim nyob rau xyoo 1950 los ntawm Popper. Lub hauv paus ntsiab lus yog:
Nyob rau hauv qhov kev txiav txim ntawm capillary quab yuam, kua silicon los yog silicon alloy nrog reactive kev ua si nkag mus rau hauv porous ceramics uas muaj carbon thiab tsim carbon silicon nyob rau hauv cov tshuaj tiv thaiv. Cov tshiab tsim silicon carbide yog sib koom ua ke rau thawj silicon carbide hais nyob rau hauv situ, thiab cov residual pores nyob rau hauv lub muab tub lim yog sau nrog impregnating tus neeg saib xyuas kom tiav cov txheej txheem densification.
Piv nrog rau lwm cov txheej txheem ntawm silicon carbide ceramics, cov txheej txheem sintering muaj cov yam ntxwv hauv qab no:
Ua haujlwm kub tsawg, lub sijhawm ua haujlwm luv luv, tsis xav tau cov cuab yeej tshwj xeeb lossis kim;
Cov tshuaj tiv thaiv Bonded qhov chaw uas tsis muaj shrinkage lossis hloov loj;
Ntau txoj kev molding (extrusion, txhaj tshuaj, nias thiab nchuav).
Muaj ntau txoj hauv kev rau shaping. Thaum lub sij hawm sintering, loj loj thiab complex cov khoom yuav ua tau yam tsis muaj pressurization. Lub Reaction Bonded thev naus laus zis ntawm silicon carbide tau kawm rau ib nrab xyoo pua. Cov tshuab no tau dhau los ua ib qho ntawm kev tsom mus rau ntau yam kev lag luam vim nws qhov tshwj xeeb zoo.
Post lub sij hawm: May-04-2018