Zirconia Toughened Alumina

Zirconia zolimba alumina (ZTA) ndi zida zapamwamba za ceramic zomwe zimagwiritsidwa ntchito kwambiri posindikiza ma valve, tchire, zida zapampu ndi zida zodulira chifukwa cha mphamvu zake komanso kukhazikika kwamankhwala – monga umboni ndi kuthekera kwake kupirira katundu wolemera popanda kuwonongeka kwakukulu.

ZTA ili ndi kukana kutenthedwa kwa kutentha ndipo imatha kupirira kusintha kwadzidzidzi kutentha, komanso kusinthasintha kwa kutentha kwachangu. Werengani kuti mudziwe zambiri zamakina ake!

Kuuma

Zirconia yowonjezeredwa ku matrix a alumina imawonjezera kuuma kwake, kulimba kwa fracture ndi flexural mphamvu pamene akuwonjezera kukana kuvala ndi kukokoloka. Njira yomwe nthawi zambiri imakhudzidwa ndikusintha kwa gawo komwe kumatsatiridwa ndi mapangidwe a microcrack koma kuyeneranso kuphatikizira malingaliro amalingaliro opsinjika momwe angagwiritsire ntchito..

Metastable tetragonal zirconia imapanga kubalalitsidwa kwabwino mkati mwa alumina matrix imatha kusinthidwa modzidzimutsa kukhala mawonekedwe a monoclinic pamene zoletsa zawo zimachotsedwa pakufalitsa ming'alu., kupereka mphamvu zolimbana ndi kupsinjika komwe kumayendetsa kufalitsa ming'alu.

ZTA ceramic ili ndi kulimba kwapang'onopang'ono komanso kuuma kwambiri poyerekeza ndi zida zina zaumisiri zopangidwa ndi oxide, komanso kuwirikiza kawiri kuchuluka kwa kutopa kwa Y-TZP. Motero, katundu wake kupanga kukhala oyenera ntchito amafuna kwambiri kuvala kukana, inertness mankhwala ndi mikangano otsika komanso mphamvu mkulu ndi kuuma.

Flexural Mphamvu

ZTA ceramics zitha kupangidwa posintha chiŵerengero cha yttria stabilized zirconia (Y-TZP) mkati mwa matrix a alumina pogwiritsa ntchito kukanikiza kotentha kwa isostatic, kukhathamiritsa kulimba-kuwonongeka kwamphamvu-kuphatikiza kwamphamvu kwamphamvu komwe kumapangitsa kuti asatope kwambiri kuposa ma ceramics apamwamba kwambiri..

Metastable Y-TZP mu alumina matrix imapangitsa kuti pakhale ma tetragonal-monoclinic transformation phase agglomerates omwe amawonjezera kulimba kwa fracture kudzera pakulimba kwa gawo. (Clausen 1976). Makamaka kuwoloka ming'alu, izi kusintha agglomerates adzakhala compress zone patsogolo mng'alu kutsogolo ndi kuchepetsa kupitirira kwake, pamapeto pake kumawonjezera kulimba kwa fracture.

Kapangidwe kazinthu izi kwapangitsa kuti pakhale zida za alumina-zirconia monga BIOLOX Delta., amagwiritsidwa ntchito kwambiri m'malo mwa chiuno chonse ndi zigawo zina zamafupa zonyamula katundu. Ceramic biomaterial iyi imakhala ndi kukana kovala bwino, inertness mankhwala pa firiji, Thermal shock resistance komanso kusagwira bwino ntchito kwamankhwala pamatenthedwe onse.

Kukaniza kwa Corrosion

Chemical inert komanso kugonjetsedwa ndi kutentha kwambiri ndi kuvala, imapereka magwiridwe antchito apamwamba poyerekeza ndi 99 alumina ceramics ndipo ndiyotsika mtengo kwambiri.

Zirconia imakhalanso ndi mphamvu zochititsa chidwi, flexural ndi elasticity katundu ndi biocompatibility – kupangitsa kuti ikhale yoyenera kugwiritsidwa ntchito pazachipatala monga kusintha m'chiuno. Chifukwa cha kusintha toughening pansi mikhalidwe nkhawa, zirconia particles kusintha kuchokera metastable tetragonal mawonekedwe monoclinic, kuthandizira kutseka ming'alu bwino ndikuwonjezera kulimba kwa fracture.

CeramTec (Biolox Delta) imagulitsa gulu la alumina-zirconia komwe zirconia yosakhazikika imakhalabe mu gawo la tetragonal kuti ithetse kusinthaku ndikupereka nsonga yosokoneza komanso kupatuka., kuwonjezera kulimba kwa alumina matrix. Zirconia zomwe zili muzinthu zimatha kusinthidwa kudzera mukukonzekera ufa ndi njira zochepetsera.

Thermal Shock Resistance

Zirconia yowonjezeredwa ku matrix oyambira aluminiyamu panthawi ya sintering imatha kukulitsa mphamvu zake komanso kulimba kwake, kupanga zomwe zimadziwika kuti ZTA (Zirconia Toughened Alumina), Kupambana ma ceramic ceramics wamba pamakina ndi kuvala.

Zirconia toughened alumina imadziwika chifukwa cha zinthu zake zapadera monga kuuma kotentha kwambiri komanso mphamvu yakukwatulidwa., inertness mankhwala pa firiji, kutsika kwamafuta owonjezera komanso kukana kugwedezeka kwamphamvu kwamafuta – katundu abwino kwa zigawo zikuluzikulu mphero komanso kuvala mbali amafuna njira kuzirala.

CeramTec imagulitsa ZTA yotchedwa Biolox delta yomwe imakhala ndi matrix a alumina okhala ndi tinthu tating'ono ta Y-TZP. (17 kulemera/wt%) ndi mapulateleti a strontium aluminate (0.5 kulemera/wt%), Kupereka kuphatikiza kothandiza kwa njira zosinthira gawo la tetragonal-to-monoclinic ndi njira zosinthira ming'alu kuti zikhale zolimba., zomwe zimapangitsa izi kukhala zoyenera pamachitidwe oyambira a THA pazachikazi.

Magetsi Insulation

Zirconia-toughened alumina imatha kupirira kugwedezeka kwamafuta popanda kusweka kapena kusweka pakusintha kwadzidzidzi kutentha., zikomo chifukwa cha tinthu tating'ono ta aluminiyamu timene timabalalika mkati mwa matrix ake omwe amamwa mphamvu zamatenthedwe ndikupanga kupsinjika komwe kumalepheretsa kusweka..

Alumina-zirconia ceramic ndi wandiweyani kwambiri kuposa mnzake weniweni wa zirconia, kupanga kukhala yabwino kwa magetsi insulation applications. Komanso, Kukula kwake kwamafuta ochepa kuposa zirconia kumapangitsa kuti ikhale yoyenera mbali zomwe zimafunikira kuziziritsa.

Kusintha kwamphamvu kwa ma composites a Alumina-zirconia kumapereka maubwino ena; Pano, Mbewu za zirconia mu alumina matrix zimadutsa gawo losasunthika pomwe mbewu zawo zimasinthidwa kuchoka ku tetragonal kupita ku monoclinic, motero kuchepetsa kung'amba komwe kumayambitsa kupsinjika powonjezera kukana motsutsana ndi abrasion ndi mphamvu. Alumina toughened zirconia nthawi zambiri imachitika chifukwa cha pyrophoric reaction yokhudza Zirconium(IV) oxide octahydrate, Aluminiyamu Nitrate Nanohydrate Triethylamine ndi HNO3(Nitric Acid); kuonjezera kukula kwa tinthu kumathandizanso kubalalitsidwa kwa njere za metastable zirconia.