Zirconia Toughened Alumina – Amandla awondisiweyo okuGqwesa kuShishino

Zirconia Toughened Alumina (ZTA) yiceramic ekhethekileyo, yahlulwe ngokuqina okuphezulu kunye nokumelana nokuqhekeka ngenxa ye-yttria ezinzisiweyo zamasuntswana e-zirconia asasazwe nge-alumina matrix..

Esi sixhobo sinokumelana nokutshintsha kweqondo lokushisa ngokukhawuleza ngaphandle kokuqhekeka okanye ukuphuka, ixhathisa ukubola kweekhemikhali kwaye inika ukuxhathisa ukothuka kwe-thermal.

Ukuchasa okugqwesileyo kokuCorrosion

I-ceramics ye-ZTA inika ibhalansi efanelekileyo phakathi kwamandla kunye nexabiso, ukuba namandla kuneemveliso ze-alumina kodwa ixabiso elincinci kune-zirconia ecocekileyo. Iimpawu zabo zoomatshini – ukwaphuka kokuqina, amandla okuguquguquka kunye nobunzima kunye nokuxhathisa ukothuka kwe-thermal – benze ukuba bafanelekele ukwenza izixhobo zoshishino ezifana nokusika amavili.

I-ZTA ifezekisa iipropati zayo eziphezulu ngenxa yokongezwa kwe-yttria ezinzile zirconia (YSZ) amasuntswana ngaphakathi kwe-alumina matrix. Xa zisasazwe ngokulinganayo kulo lonke, I-YSZ inceda ukonyusa ubulukhuni bokuqhekezwa kokuqina kunye nokomelela kwazo zombini ezi zinto zikhokelela ekuxhathiseni okukhethekileyo., Inertness yekhemikhali kwiqondo lobushushu begumbi kunye nobulukhuni obushushu/iempawu zamandla okuxhwila kwimathiriyeli yeceramic ekhethekileyo.

ZTA iimveliso’ iimpawu zoomatshini zixhomekeke kakhulu kwiindlela zabo zokusetyenzwa kokuvelisa umgubo, kuquka unyango lobushushu, iindlela zokubala, iindlela zokomisa kunye neenkqubo ze-sintering kunye nokubunjwa okulungiselelwe kunye nezongezo ezongeziweyo ngexesha lemveliso. Zonke ezi zinto zinefuthe elikhawulezileyo kumandla azo, ukuqina kunye neempawu zokuqina.

Okugqwesileyo kweThermal Shock Resistance

Iiseramics ze-ZTA zibonelela ngokugqwesileyo kokuxhathisa ukothuka kwe-thermal, ukubenza babe lolona khetho lubalaseleyo kwizicelo ze-aerospace ezifuna amanqanaba aphezulu amandla, ubunzima, kunye ne-inertness yekhemikhali. Xa usasazwe ngokufanayo ngaphakathi kwe-alumina matrix YSZ inokuphuculwa. Olunye olulolo hlobo lwe-zirconia-alumina ceramic yoguquko esilunikezayo yiBIOLOX delta enokufunyanwa isetyenziselwa izinto ezithwala i-orthopedais njengokutshintshwa kwenyonga..

Utshintsho olubangelwa luxinzelelo ukusuka kwi-metastable tetragonal ukuya kwisakhiwo se-monoclinic ye-YSZ ivelisa ukwanda komthamo kunye noxinzelelo lwe-chear oluchasene nokwanda kokuqhekeka., ukwanda kokuqina kokwaphuka ngelixa ngaxeshanye kuphuculwa amandla athambileyo. Ukusebenza kwe-alumina-YSZ yoguqulo-oluqilima lweseramiki kuxhomekeke kwiimeko zokusetyenzwa kunye nakwi-stoichiometry yayo yee-oxides eziyinxalenye kwinkqubo yokuntywila..

Ukulawulwa kakubi kweemeko ze-sintering kunokubangela amandla aphantsi okuguquguqukayo kunye ne-homogeneity embi ye-alumina-YSZ matrix., enokubakho ngenxa entrapment komoya okanye amasuntswana agglomeration. Ngokudibanisa izongezo ezifana neyttria okanye i-magnesium oxides, omnye unokunciphisa i-tetragonal ukuya kwi-monoclinic yokuguqulwa kweqondo lokushisa kunye nokuphucula iimpawu ze-zirconia ze-sintering.

UkuGqiba okugqwesileyo kokumelana

I-ZTA ayigqwesi kuphela ngokwemiqathango yokuxhathisa ukothuka kwe-thermal kunye nokumelana nokubola, kodwa iyakwazi ukumelana nokunxitywa kakhulu ngenxa yenguqu yesigaba se-tetragonal-monclinic encasing indlela. Ngaphaya koko, Uphononongo lwe-in vitro lubonise ukuba amacandelo e-ZTA awathandeki kangako ekuthotyweni kwe-hydrothermal – into ebaluleke kakhulu ekutshintsheni i-hip esikhundleni sentloko ye-femoral kunye neeseramikhi zekomityi (njenge-BIOLOX delta eveliswe yiCeramTec).

Uvavanyo lokunxiba olufanisiweyo olwenziwe kwizinto ze-ZTA ezenziwe ngezinto ezihlanganisiweyo ze-alumina-zirconia zivelise iziphumo ezichukumisayo malunga nokuxhathisa ukunxiba., amandla okuguquguquka kunye nobunzima. Iisampulu ze-ZTA ezivezwe kwimijikelo emininzi kwi-simuli ye-hip ibonise ukuthotywa okuncinci kunye noburhabaxa obusezantsi kakhulu kunamalungu e-monolithic zirconia..

Amacandelo e-ZTA abonakalise ukuba afanelekile kwizicelo ezifunwayo kwimveliso yeemoto (isixhobo sokwenza izixhobo ezishushu nezibandayo, ii-roller ezivaliweyo kunye neecapstan); ishishini lamandla (iibheringi, ukufakwa kwe-orifice kunye nabafumani be-vortex); ukulungiswa kokutya (iinxalenye impompo homogenizing); kunye noshishino lwamandla. Iimpawu zabo zomatshini zixhomekeke kwizinto ezininzi eziguquguqukayo: iindlela zokulungiselela ezisetyenziselwa ukulungisa umgubo; iindlela zokomisa ezisetyenziswa ngexesha calcination; iindlela zokubunjwa ezamkelwe ngexesha lobuchule be-sintering; ukumila okulungiselelwe; izongezo ezongeziweyo kunye nokuhanjiswa kobungakanani besuntswana phakathi kwabanye.

Amandla agqwesileyo

Ii-ceramics ze-ZTA zisebenzisa i-stress-induced transformation ukudibanisa i-zirconia kwi-matrix ye-alumina, ukwandisa amandla kunye nokuqina ngokuhamba kwexesha. Oku kwenza i-ZTA ibe sisisombululo esigqwesileyo se-ceramic kwizicelo zamashishini ezifuna ukuqina, ukumelana nomhlwa okuphezulu, ukunyamezela ukothuka kwe-thermal kunye nokunyamezela ukothuka kwe-thermal.

Ngaphantsi koxinzelelo, i-tetragonal metastable precipitates kwi-cubic alumina itshintsha ngequbuliso ibe ngamasuntswana e-monoclinic athi anyuse ukuqina kwawo ngokwaphuka kwawo ngokwenza imigangatho ecinezelweyo yomphezulu ebambelela kwiintanda ngaphakathi kwe-matrix yayo..

Ukuguqulwa kokuqina yinto eyaziwa ngokuba yi-fracture toughening, apho ukonyuka kokuqina kokuqina kwe-alumina kukhokelela kubude obufutshane bokuqhekeka, i-crack blunting encinci, kunye nokusebenzisana okuphuculweyo kunye ne-microcracks esele ikhona. Oku kuvumela ukudityaniswa okuqinileyo kunye nokuqinileyo-kwi-soft ezisetyenziswa kwiiseramikhi zangoku zonyango ezifana nokutshintshwa kwenyonga.. Ngaphaya koko, Ufakelo lwe-zirconia oluzinzisiweyo lwe-Yttrium olubizwa ngokuba yi-y-TZP lubonelela ngokhuseleko ekunxityweni kwexesha.