Zirconia Toughened Alumina – Amandla Athuthukisiwe Okuphumelela Kwezimboni

Zirconia Toughened Alumina (I-ZTA) i-ceramic eyingqayizivele, ihlukaniswa ngokuqina okuphezulu nokumelana nokuphuka ngenxa yezinhlayiya ze-zirconia ezizinzile ze-yttria ezihlakazwe nge-alumina matrix..

Lesi sici singamelana noshintsho olusheshayo lokushisa ngaphandle kokuqhekeka noma ukuphuka, imelana nokugqwala kwamakhemikhali futhi inikeza ukumelana nokushaqeka okuhle kakhulu okushisayo.

Ukumelana Nokugqwala Okuhle Kakhulu

Izitsha zobumba ze-ZTA zinikeza ibhalansi ekahle phakathi kwamandla nenani, ukuba namandla kunemikhiqizo ye-alumina kodwa kubiza kancane kune-zirconia ehlanzekile. Izici zabo mechanical – ukuqina kwe-fracture, amandla okuguquguquka nobulukhuni kanye nokumelana nokushaqeka okushisayo – zenze zifaneleke ukwenza amathuluzi ezimboni ezifana namasondo okusika.

I-ZTA ifinyelela izakhiwo zayo eziphakeme ngenxa yokwengezwa kwe-yttria ezinzile zirconia (YSZ) izinhlayiya ngaphakathi kwe-alumina matrix. Lapho kuhlakazwa ngokulinganayo kulo lonke, I-YSZ isiza ukuqinisa kokubili ubulukhuni bokuphuka kanye namandla aqinile azo zombili izici okuholela ekugqokeni okukhethekile, ukungabi namakhemikhali kumazinga okushisa asekamereni kanye nobulukhuni obushisayo/izakhiwo zamandla okuhlwithwa kwempahla yobumba ehlukile.

Imikhiqizo ye-ZTA’ izakhiwo zemishini zincike kakhulu emizileni yazo yokucubungula ukukhiqiza izimpushana, kuhlanganise nokwelapha ukushisa, izindlela zokubala, amasu okomisa kanye nezinqubo ze-sintering kanye nokubunjwa okulungiselelwe okunezithasiselo ezingezwe ngesikhathi sokukhiqiza. Zonke lezi zici zinomphumela osheshayo emandleni azo, ukunwebeka nobulukhuni izakhiwo.

I-Thermal Shock Resistance enhle kakhulu

Ama-ceramics e-ZTA anikeza ukumelana nokushaqeka okushisayo okuhle kakhulu, ukubenza babe ukukhetha okuhle kakhulu kwezinhlelo zokusebenza ze-aerospace ezidinga amazinga aphezulu wamandla, ubulukhuni, kanye ne-inertness yamakhemikhali. Uma ihlakazwe ngokufanayo ngaphakathi kwe-alumina matrix i-YSZ ingathuthukiswa. Enye yezinto ezifana ne-zirconia-alumina ceramic eqinisiwe esinikeza i-BIOLOX delta engatholakala isetshenziselwa izingxenye ezithwala i-orthopedais ezifana nokushintshwa kwenyonga..

Ukuguqulwa okubangelwa ingcindezi ukusuka ku-tetragonal ye-metastable kuya esakhiweni se-monoclinic ye-YSZ kukhiqiza ukukhuliswa kwevolumu kanye nokucindezeleka kwe-shear okuphikisana nokusakazeka kokuqhekeka., ukwandisa ukuqina kokuphuka ngenkathi ngesikhathi esifanayo kuthuthukisa amandla okuguquguquka. Ukusebenza kweceramic eqinile ye-alumina-YSZ kuncike ezimeni zokucubungula kanye ne-stoichiometry yayo yama-oxide ahlanganisiwe enqubweni yokucwilisa..

Izimo ze-sintering ezilawulwa kabi zingase zibangele amandla aphansi aguquguqukayo kanye ne-homogeneity embi ye-alumina-YSZ matrix., okungenzeka ngenxa yokungena komoya noma ukuhlangana kwezinhlayiyana. Ngokungeza izithasiselo ezifana ne-yttria noma i-magnesium oxides, umuntu angase anciphise izinga lokushisa le-tetragonal kuya ku-monoclinic futhi athuthukise izakhiwo ze-sintering ze-zirconia.

I-Wear Resistance enhle kakhulu

I-ZTA ayiphumeleli kuphela ngokuya ngokumelana nokushaqeka okushisayo kanye nokumelana nokugqwala, kodwa futhi ayigugi kakhulu ngenxa yendlela yayo yokuguqula isigaba se-tetragonal-monclinic. Ngaphezu kwalokho, izifundo ze-in vitro ziveze ukuthi izingxenye ze-ZTA azijwayele ukuwohloka kwe-hydrothermal – okuthile okubalulekile ekushintsheni inqulu esikhundleni sekhanda lesifazane kanye nezitsha zobumba zenkomishi (njenge-BIOLOX delta ekhiqizwa yi-CeramTec).

Ukuhlolwa kokugqokwa okulingiswayo okwenziwe ezintweni ze-ZTA ezenziwe ngezinto eziyinhlanganisela ye-alumina-zirconia kukhiqize imiphumela emangazayo mayelana nokumelana nokugqokwa., amandla okuguquguquka nobulukhuni. Amasampula e-ZTA adalulwe emijikelezweni eminingi kusifanisi se-hip abonise ukuwohloka okuncane okunobugwegwe obuphansi kakhulu kunezingxenye ze-monolithic zirconia..

Izingxenye ze-ZTA zifakazele ukuthi zifanele izicelo ezidingekayo ekukhiqizeni izimoto (ukushisa nokubanda ukwakha tooling, ama-roller nama-capstans wokuvala amathini); imboni yamandla (ama-bearings, ukufakwa kwe-orifice kanye nezitholi ze-vortex); ukucubungula ukudla (izingxenye zephampu homogenizing); kanye nemboni yamandla. Izakhiwo zabo zemishini zincike ezintweni eziningi eziguquguqukayo: izindlela zokulungiselela ezisetshenziselwa ukulungisa izimpushana; izindlela zokomisa ezisetshenziswa ngesikhathi sokubala; amasu okubunjwa asetshenziswa ngesikhathi samasu we-sintering; ukubunjwa okwenziwe; izithasiselo ezengeziwe kanye nokusabalalisa usayizi wezinhlayiyana phakathi kwabanye.

Excellent Amandla

Izitsha zobumba ze-ZTA zisebenzisa uguquko olubangelwa ukucindezeleka ukuze luhlanganise i-zirconia ku-alumina matrix, ukwandisa amandla nokuqina ngokuhamba kwesikhathi. Lokhu kwenza i-ZTA ibe yisixazululo esihle kakhulu se-ceramic sezinhlelo zokusebenza zezimboni ezidinga ukuqina, ukumelana nokugqwala okuphezulu, ukubekezelela ukushaqeka okushisayo kanye nokubekezelela ukushaqeka okushisayo.

Ngaphansi kokucindezeleka, i-tetragonal metastable precipitates ku-cubic alumina ishintsha kungazelelwe ibe yizinhlayiya ze-monoclinic ezikhulisa ukuqina kwayo kokuphuka ngokwakha izendlalelo ezicindezelayo ezinamathela emifantwini ngaphakathi kwe-matrix yayo..

I-Transformation toughening yinto eyaziwa ngokuthi i-fracture toughening, lapho ukwanda kokuqina kokuphuka kwe-alumina kubangela ubude obufushane bokuqhekeka, i-crack blunting encane, kanye nokusebenzisana okuthuthukisiwe nama-microcracks asevele ekhona. Lokhu kuvumela inhlanganisela ye-hard-on-hard kanye ne-hard-on-soft bearing esetshenziswa kuma-ceramics ebanga lezokwelapha lesimanje njengokushintsha inqulu.. Ngaphezu kwalokho, Izimila ezizinzile ze-zirconia ze-Yttrium ezaziwa nge-y-TZP zinikeza ukuvikeleka ekuguge ngokuhamba kwesikhathi.