zirconia toughened alumina yatsimikizira kuti ndiyabwino kwambiri pamakina poyerekeza ndi zirconia monolithic, kuphatikiza kulimba kwa fracture ndi flexural mphamvu. Kukhazikika kwa ZTA kumachokera ku gawo la matrix lomwe limateteza ndikuletsa kusintha kwa mbewu za tetragonal zirconia., kuthandizira kupirira kuwonongeka pansi pa mikhalidwe ya in-vivo hydrothermal.
Flexural Mphamvu
Powonjezera zirconia ku alumina ceramics, zirconia toughened alumina imapangidwa. Izi zimakhala ndi mphamvu zosinthika kwambiri komanso kulimba kwamakina pakafunika, komanso amakana dzimbiri ndi mankhwala komanso kukhudzana ndi madzi am'thupi.
zirconia toughened alumina imatha kupirira kusinthasintha kwachangu kwa kutentha chifukwa cha zirconia particles zomwe zimabalalika mkati mwa alumina matrix omwe amamwa mphamvu zamatenthedwe ndikupanga kupsinjika kolimba kuti zisawonongeke., kupanga kuti ikhale yoyenera kugwiritsidwa ntchito m'mafakitale osiyanasiyana monga zida za ng'anjo ndi injini za turbine injini.
Ceramic yophatikizika iyi imaphatikiza mikhalidwe yochititsa chidwi ya alumina ndi zirconia kuti ipereke mphamvu zowonjezera komanso kukana kugwedezeka kwamafuta., ndi kuuma kwakukulu, flexural mphamvu, kulimba kwa fracture ndi kukana kuvala komwe kumaposa 99% aluminiyamu woyera ponena za kuuma, kulimba ndi kukana kuvala.
Kulimba kwa Fracture
Zirconia imakulitsa kulimba kwa fracture za aluminiyamu zadothi mwa kusintha kulimba. Pamene kumenyedwa, metastable yttrium-stabilised zirconia imasandulika kukhala makristalo a monoclinic omwe amatulutsa kupsinjika komwe kumalepheretsa kufalikira kwa mng'alu..
Zirconia toughened alumina ndi chinthu choyenera kupanga zida zodulira chifukwa cha kuuma kwake, kukhazikika kwamafuta ndi kukana kukangana. Komanso, mawonekedwe ake apamwamba amakina amathandiza kwambiri kuti azikhala olimba komanso odalirika.
ZTA yopangidwa kudzera pa gelcasting ili ndi kuphatikiza kwapadera kwamphamvu yosinthika, kulimba kwa fracture, biocompatibility ndi kukana kutentha / dzimbiri zomwe zimapangitsa kuti zikhale zoyenera kuchita opaleshoni yosinthira chiuno. Kupyolera mu njira za gelcasting ndizothekanso kusintha magawo ake olimba-fracture-flexural mphamvu posintha slurry solid loading, makulidwe a nkhungu kapena kutentha kwa sintering kuti muwonjezere zotsatira.
Ma Curve a Stress-Strain
zirconia toughened alumina zakuthupi zili ndi mphamvu zapamwamba komanso kukana kuvala, komanso kukhazikika kwapadera pothandizira zolemetsa zolemetsa popanda kupunduka popanikizika. Komanso, imadzitamandira kwambiri chifukwa cha kugwedezeka kwamafuta komwe kumawathandiza kupirira kusinthasintha kwadzidzidzi kwa kutentha popanda kuwonongeka.
Zirconia zomwe zili pamwamba pa malire ena zimawonjezera kuwonongeka kwa ukalamba kudzera m'ma microcracks omwe amapangidwa panthawi yozizira pambuyo pozizira, zomwe zimakhala ngati njira zolowera madzi muzinthu zadothi., zomwe zimapangitsa kuti ma microcracks apangidwe panthawi yozizira yomwe imakhala ngati njira zolowera ndikufalikira mmenemo. Mosiyana ndi zimenezo, pamene pansi pa chipilala ichi, zirconia particles zimasintha kuchokera ku tetragonal kupita ku monoclinic zomwe zimachepetsa kukalamba..
Kulimba kwamakokedwe
Zirconia toughened alumina ndi chinthu cholimba komanso chokhazikika chokhala ndi kukana kwabwino kwambiri komanso kukhazikika kwamafuta, kuzipangitsa kukhala zoyenera kwa zigawo zomwe zimafuna kuziziritsa. Kuphatikiza apo, malo okhazikika ngati awa amapereka kuwongolera kwamafuta komanso kukana kwamphamvu kumawapangitsa kukhala abwino kusankha zinthu..
Pansi pa nkhawa, ZTA imasinthidwa kuchokera ku tetragonal kupita ku monoclinic yomwe imalepheretsa kufalikira kwa crack ndikuwonjezera kulimba kwa fracture., koma kafukufuku wina amasonyeza kuti kuwonjezeka kwa zirconia kosakhazikika kumabweretsa kuchepa kwa mphamvu.
ZTA ceramics nthawi zambiri zimakhala 10%-20% zirconia, zomwe zimalola kuti zigwirizane ndi pulogalamu iliyonse. ZTA ndi biocompatible, kupirira kutentha, zosagwira dzimbiri, cholimba mokwanira kupirira kukakamizidwa, njira yotsika mtengo yopangira zirconia ceramics yoyera ndipo imatha kupirira kutentha kwambiri popanda kuwonongeka. Opanga zisindikizo za mavavu nthawi zambiri amachisankha chifukwa chokana dzimbiri komanso kupirira – makhalidwe onse abwino kwa mavavu chisindikizo ntchito.
Mphamvu Zamphamvu
zirconia toughened alumina ndi yosagwira dzimbiri ndipo ili ndi mphamvu zapadera zamakina, kuwapanga kukhala oyenera ntchito zomwe zimafuna kuuma ndi kulimba nthawi imodzi. Komanso, ZTA imapereka ndalama zopulumutsira pazitsulo zoyera za zirconia.
Kuphatikiza alumina ndi zirconia kumapanga ceramic yokhala ndi mphamvu zosinthika kwambiri, kulimba kwa fracture, ndi kuvala kukana kuposa aluminiyamu koyera. Itha kupirira zolemetsa zambiri komanso kukhudzidwa ndipo nthawi zambiri imagwiritsidwa ntchito ngati kukweza kwa alumina wamba pamapangidwe omwe amafunikira zina zowonjezera..
Kusintha kwamphamvu kumawonjezera mphamvu iyi; pansi pa zovuta, Zirconia particles amasintha kuchoka ku tetragonal kukhala mawonekedwe a monoclinic ndikukula, kukanikiza ming'alu mu matrix a alumina ndipo motero kumabweretsa kulimba kwapamwamba kuposa YSZ (Zithunzi 6c ndi d).
Kukaniza kwa Corrosion
Kuphatikiza kwa alumina ndi zirconia kwa ZTA ceramic kumapereka kukana kwa dzimbiri kwapamwamba poyerekeza ndi koyera 99% zipangizo za aluminiyamu zokha, ndipo ali ndi kuuma kwakukulu, kulimba kwa fracture, flexural mphamvu, ndi kuuma katundu kuposa mpikisano wake.
ZTA imakhala ndi mavalidwe apamwamba komanso kukana kwa abrasion komanso kuyanjana kwamankhwala, kupanga kukhala yabwino kwa mafakitale ntchito amafuna mkulu makina durability. Komanso, kuphatikiza kwa zinthu kumadzitamandira kwambiri kukana kugwedezeka kwamafuta komwe kumalola kusintha kwachangu kutentha popanda kusweka kapena kusweka.
Zirconia particles zomwe zimawonjezeredwa ku alumina matrix zimawonjezera kulimba kwake kwa fracture chifukwa cha kusintha kwamphamvu., zotsatira zomwe zimadza chifukwa cha kupsinjika kwa zirconia particles zomwe zimasintha kuchoka ku tetragonal kupita ku monoclinic crystal structures pamene akukumana ndi kupsinjika maganizo., kutulutsa kupsyinjika komwe kumalepheretsa kufalikira kwa mng'alu ndikuwonjezera kwambiri kulimba kwake.
Thermal Shock Resistance
zirconia toughened alumina ndi ceramic yapamwamba yomwe imaphatikiza alumina ndi zirconia. Kupanga ZTA, zirconia imalowetsedwa muzitsulo zazikulu za alumina isanayimidwe kuti iwonjezere mphamvu komanso kukana kutenthedwa kwa kutentha pazitsulo zamtundu wa alumina.; Komanso imadzitamandira kuuma kwakukulu, flexural mphamvu, ndi kachulukidwe kuposa mnzake.
ZTA toughening mechanism imaphatikizapo kusinthika kwa gawo lopangitsa kupsinjika kuchokera ku tetragonal kupita ku monoclinic zirconia particle crystal structures., kukulitsa kulimba kwa fracture ndikuyiteteza ku kugwedezeka kwamafuta ndi ma abrasion amawotchi. zirconia toughened alumina ndi biocompatible kwambiri ndipo si dzimbiri msanga, kuzipangitsa kukhala zabwino zosindikizira ma valve. Komanso, mphamvu yake yosunthika kwambiri imalola kupirira kupanikizika kwa thupi moyenera.