teknoloji ya sintering ya jekeseni wa ceramic

Monga gawo lofunikira la zida zauinjiniya ndi zida zogwirira ntchito, zida zapamwamba za ceramic zili ndi chiyembekezo chogwiritsa ntchito mphamvu zatsopano, zamagetsi zolumikizirana, semiconductor, mlengalenga ndi magawo ena amakampani. Komabe, chifukwa ufa wa ceramic nthawi zambiri ndi ionic chomangira kapena covalent bond pawiri, chikhalidwe sintering ndondomeko kukonzekera wandiweyani.zipangizo za ceramickumafuna kutentha kwambiri kwa sintering ndi nthawi yayitali yogwira, zomwe zimatsogolera ku mbewu zowonongeka ndi zotsalira za porosity, ndiyeno zimakhudza katundu wajekeseni wa ceramic. Kuti muchepetsezitsulo sinteringkutentha, kufupikitsa sintering nthawi, kusintha kachulukidwe sintering ndi katundu chuma, ofufuza apanga zosiyanasiyana umisiri watsopano sintering.

Spark plasma sintering (SPS)

Ukadaulo wa SPS ndi mtundu watsopano waukadaulo wofulumira wa sintering womwe wakhala ukukhudzidwa kwambiri ndikuphunziridwa m'maphunziro apamwamba. CHITH. 1 ikuwonetsa mfundo zake zogwirira ntchito.

Tekinoloje ya SPS idayambitsa kuyambitsa kwa dc pulse current mundondomeko ya sintering. The indenter imagwira ntchito ngati chonyamulira chapano kuti chidutse pomwe ikugwiritsa ntchito kukakamiza pazinthuzo. Mosiyana ndi njira zachikhalidwe zoyatsira, zomwe nthawi zambiri zimagwiritsa ntchito kutentha kwamoto, SPS imagwiritsa ntchito mphamvu yamagetsi yayikulu yomwe imadutsa mu nkhungu kapena kuchititsa zitsanzo kuti itenthetse zinthuzo. Pakuti insulating zitsanzo, graphite ndi madutsidwe wabwino magetsi nthawi zambiri ntchito nkhungu zinthu, ndi kukana kutentha nkhungu ntchito kuti chitsanzo nyamuka mofulumira. Kwa zitsanzo conductive, ndi insulating nkhungu angagwiritsidwe ntchito kutentha panopa mwachindunji mwa chitsanzo. Kutentha kwa kutentha kumatha kufika 1000 ℃ / min. Pamene kutentha kwachitsanzo kufika pamtengo wokhazikitsidwa, sintering ikhoza kumalizidwa pakapita nthawi yochepa yosungira kutentha.

Ukadaulo wa SPS uli ndi maubwino a kutentha kwa sintering, nthawi yochepa yogwira, kutentha kwachangu, kusinthasintha kwa sintering, ndi kuphatikiza kwamitundu yambiri (magetsi-mechanical-thermal).

Flash sintering (FS)

Ukadaulo wa FS udanenedwa koyamba mu 2010 ndi Cologna et al waku University of Colorado, kutengera kafukufuku waukadaulo wothandizira zitsulo zachitsulo (FAST)

Ukadaulo wa FS makamaka umakhudza magawo atatu azinthu, zomwe ndi kutentha kwa ng'anjo (Tf), mphamvu yakumunda (E) ndi pano (J). Chithunzi 3C chikuwonetsa kusinthika kwa gawo lililonse munjira yachikhalidwe ya FS. Munjira iyi, magetsi okhazikika amagwiritsidwa ntchito pazinthu zakuthupi ndipo kutentha kwa ng'anjo kumakwera nthawi zonse. Pamene kutentha kwa ng'anjo kuli kochepa, resistivity yakuthupi imakhala yochuluka ndipo yomwe ikudutsa muzinthuzo ndi yaying'ono. Ndi kuwonjezeka kwa kutentha kwa ng'anjo, chitsanzo cha resistivity chimachepa ndipo panopa chikuwonjezeka pang'onopang'ono. Gawoli limatchedwa siteji ya incubation ndipo dongosolo limayendetsedwa ndi magetsi. Pamene kutentha kwa ng'anjo kumakwera kutentha kwakukulu, mphamvu ya resistivity imatsika mwadzidzidzi, panopa ikukwera kwambiri, ndipo FS imapezeka. Popeza mphamvu yam'munda ikadali yokhazikika panthawiyi, mphamvu yamagetsi (W = EJ) idzafika mofulumira ku malire a mphamvu yamagetsi, ndipo dongosolo lidzasintha kuchoka ku mphamvu yamagetsi kupita ku mphamvu zamakono, zomwe zimatchedwa FS siteji. Pamene resistivity wa zinthu si kuwuka, munda mphamvu okhazikika kachiwiri, ndi sintering amalowa siteji khola, ndiko kuti, siteji kutchinjiriza FS. Pambuyo pa siteji ya insulation, ndondomeko yathunthu ya FS imatha.

Poyerekeza ndi sintering chikhalidwe, FS ali ndi ubwino zotsatirazi: kufupikitsa sintering nthawi ndi kuchepetsa ng'anjo kutentha chofunika sintering, ziletsa kukula kwa tirigu, akhoza kukwaniritsa sanali equilibrium sintering, zipangizo zosavuta, otsika mtengo.