Zirconia Toughened Alumina – Mphamvu Zowonjezereka za Kuchita Bwino Kwambiri kwa Industrial

Zirconia Toughened Alumina (ZTA) ndi ceramic yapadera, chosiyanitsidwa ndi kulimba kwakukulu ndi kukana kwa fracture chifukwa cha yttria yokhazikika ya zirconia particles omwazikana kupyolera mu alumina masanjidwewo..

Nkhaniyi imatha kupirira kusintha kwa kutentha kwachangu popanda kusweka kapena kusweka, imalimbana ndi dzimbiri zamankhwala ndipo imapereka kukana kwamphamvu kwamafuta.

Kukaniza Kwabwino Kwambiri kwa Corrosion

ZTA ceramics imapereka malire abwino pakati pa mphamvu ndi mtengo, kukhala wamphamvu kuposa zinthu za aluminiyamu koma zotsika mtengo kuposa zirconia zoyera. Awo makina katundu – kulimba kwa fracture, flexural mphamvu ndi kuuma komanso kutentha kutentha kukana – kuwapanga kukhala oyenera kupanga zida zamakampani monga kudula mawilo.

ZTA imakwaniritsa zinthu zake zapamwamba chifukwa chowonjezera yttria yokhazikika zirconia (YSZ) particles mkati mwa alumina matrix. Pamene omwazikana wogawana lonse, YSZ imathandizira kukhathamiritsa kulimba-kuphwanyika komanso kulimba kwazinthu zonse ziwiri zomwe zimapangitsa kukana kwapadera, kusakhazikika kwamankhwala kutentha kwachipinda ndi kuuma kotentha / kukwatulidwa kwamphamvu kwazinthu zapadera za ceramic.

ZTA mankhwala’ makina katundu zimadalira kwambiri pokonza njira zawo zopangira ufa, kuphatikizapo kutentha mankhwala, njira za calcination, kuyanika njira ndi njira zopangira sintering komanso mawonekedwe osinthika okhala ndi zowonjezera zomwe zimawonjezeredwa panthawi yopanga. Zinthu zonsezi zimakhudza mphamvu zawo nthawi yomweyo, elasticity ndi kuuma katundu.

Kukaniza Kwabwino Kwambiri kwa Thermal Shock

ZTA ceramics imapereka kukana kwamphamvu kwamafuta, kuwapanga kukhala chisankho chabwino kwambiri pamapulogalamu apamlengalenga omwe amafunikira mphamvu zambiri, kulimba, ndi inertness mankhwala. Mukabalalitsidwa mofanana mkati mwa alumina matrix YSZ ikhoza kukonzedwa. Chimodzi mwa zosinthika-zolimba za zirconia-alumina ceramic zomwe timapereka ndi BIOLOX delta yomwe ingagwiritsidwe ntchito popanga zida zonyamula katundu za orthopedais monga zosinthira m'chiuno..

Kusintha kochititsa kupsinjika kuchokera ku metastable tetragonal kupita ku monoclinic ya YSZ kumabweretsa kukulitsa kwa voliyumu ndi kumeta ubweya komwe kumalimbana ndi kufalikira kwa crack., kuonjezera kulimba kwa fracture pomwe nthawi imodzi kumapangitsa kuti flexural mphamvu. Kuchita kwa alumina-YSZ kusinthika-wolimba ceramic kumadalira momwe zinthu zimagwiritsidwira ntchito komanso pa stoichiometry yake ya ma constituent oxides mu sintering process..

Kusayendetsedwa bwino kwa sintering kumatha kupangitsa kuti pakhale mphamvu zochepa zosinthika komanso kusayenda bwino kwa matrix a alumina-YSZ., mwina chifukwa mpweya entrapment kapena tinthu agglomeration. Powonjezera zowonjezera monga yttria kapena magnesium oxides, wina akhoza kuchepetsa tetragonal kuti monoclinic kusintha kutentha ndi kuonjezera zirconia sintering katundu.

Kukaniza Kwabwino Kwambiri

ZTA sikuti imangopambana pakukana kugwedezeka kwamafuta komanso kukana kwa dzimbiri, komanso imakhala yosamva bwino chifukwa cha njira yake yosinthira gawo la tetragonal-monclinic. Komanso, maphunziro a in vitro awonetsa kuti zigawo za ZTA sizimakonda kuwonongeka kwa hydrothermal – chinthu chofunika kwambiri m'malo mwa chiuno cha femoral head and cup ceramics (monga BIOLOX delta yopangidwa ndi CeramTec).

Mayeso oyeserera ovala opangidwa pazigawo za ZTA zopangidwa ndi alumina-zirconia opangidwa ndi zinthu zophatikizika atulutsa zotulukapo zochititsa chidwi pankhani ya kukana kuvala., flexural mphamvu ndi kuuma. Zitsanzo za ZTA zomwe zimawonetsedwa mozungulira kangapo mu choyeserera cha chiuno zidawonetsa kuwonongeka pang'ono ndi kutsika kotsika kwambiri kuposa zida za monolithic zirconia..

Zida za ZTA zatsimikizira kuti ndizoyenera kugwiritsa ntchito popanga magalimoto (otentha ndi ozizira kupanga tooling, zodzigudubuza zotsekera ndi capstans); makampani opanga mphamvu (mayendedwe, orifice inserts ndi vortex finders); kukonza chakudya (homogenizing mpope zigawo); ndi mafakitale amagetsi. Zochita zawo zamakina zimadalira mitundu yambiri: njira zopangira zopangira ufa; kuyanika njira ntchito calcination; njira zomangira zomwe zimatengedwa panthawi ya njira za sintering; mawonekedwe opangidwa; zowonjezera anawonjezera ndi tinthu kukula kugawa pakati pa ena.

Wabwino Mphamvu

ZTA Ceramics amagwiritsa ntchito kusintha koyambitsa kupsinjika kuti aphatikize zirconia kukhala matrix a alumina, kuonjezera mphamvu ndi kulimba pakapita nthawi. Izi zimapangitsa ZTA kukhala yankho labwino kwambiri la ceramic pamafakitale omwe amafunikira kulimba, kukana dzimbiri, kulekerera kwamphamvu kwamafuta ndi kulekerera kwamphamvu kwamafuta.

Pansi pa kupsyinjika, tetragonal metastable precipitates mu cubic alumina amasinthidwa mwadzidzidzi kukhala tinthu tating'onoting'ono tomwe timakulitsa kulimba kwake popanga zigawo zolimba zomwe zimamatira ming'alu mkati mwa matrix ake..

Kusintha toughening ndi chodabwitsa chotchedwa fracture toughening, momwe kuchuluka kwa kuphulika kwa alumina kumapangitsa kuti ming'alu ikhale yayifupi, kuchepa pang'ono blunting, and improved interactions with preexisting microcracks. This allows hard-on-hard and hard-on-soft bearing combinations which are used in modern medical-grade ceramics such as hip replacements. Komanso, Yttrium stabilized zirconia implants known as y-TZP provide protection from wear over time.