Umthelela we-sintering ezakhiweni ze-zirconia ceramics

Umthelela we-sintering ezakhiweni ze-zirconia ceramics

Njengohlobo lwempahla ye-ceramic, i-zirconium inamandla amakhulu, ubulukhuni obukhulu, ukumelana okuhle kokugqoka, ukumelana ne-asidi ne-alkali, ukumelana nokushisa okuphezulu nezinye izakhiwo ezinhle kakhulu. Ngaphezu kokusetshenziswa kabanzi emkhakheni wezimboni, ngokuthuthuka ngamandla kwemboni yamazinyo okufakelwa eminyakeni yamuva nje, i-zirconia ceramics ibe yizinto ezingaba khona kakhulu zamazinyo okufakelwa futhi yadonsa ukunaka kwabacwaningi abaningi.

Ukusebenza kwe-zirconia ceramics kuzothinteka yizici eziningi, namuhla sikhuluma ngomthelela we-sintering kwezinye izakhiwo ze-zirconia ceramics.

Indlela ye-Sintering

Indlela yendabuko ye-sintering ukushisa umzimba ngokusebenzisa ukushisa kwemisebe, ukushisa ukushisa, ukushisa ukushisa, ukuze ukushisa kuvele ebusweni be-zirconia kuya ngaphakathi, kodwa ukuqhutshwa kokushisa kwe-zirconia kubi kakhulu kune-alumina nezinye izinto zobumba. Ukuze uvimbele ukuqhekeka okubangelwa ukucindezeleka okushisayo, isivinini sokushisa esivamile sihamba kancane futhi isikhathi eside, okwenza umjikelezo wokukhiqiza we-zirconia ubude futhi izindleko zokukhiqiza ziphezulu. Eminyakeni yamuva nje, ukuthuthukisa ubuchwepheshe bokucubungula i-zirconia, ukunciphisa isikhathi sokucubungula, ukunciphisa izindleko zokukhiqiza, kanye nokuhlinzeka ngokusebenza okuphezulu kwezinto zokwakha ze-ceramic zirconia zamazinyo sekugxilwe kuzo ucwaningo, futhi i-microwave sintering ngokungangabazeki iyindlela ethembisayo ye-sintering.

Kutholakala ukuthi i-microwave sintering kanye ne-atmospheric pressure sintering ayinawo umehluko obalulekile ethonyeni lokungena kancane kanye nokumelana nokugqokwa. Isizathu siwukuthi ukuminyana kwe-zirconia etholwe yi-microwave sintering kufana nalokho okujwayelekile kwe-sintering, futhi kokubili kuyi-sintering eminyene, kodwa izinzuzo ze-microwave sintering izinga lokushisa eliphansi le-sintering, isivinini esisheshayo kanye nesikhathi esifushane se-sintering. Kodwa-ke, izinga lokushisa lokuphakama kwe-atmospheric pressure sintering lihamba kancane, isikhathi sokucwilisa sinde, futhi sonke isikhathi se-sintering silinganiselwa ku-6-11h. Uma kuqhathaniswa ne-pressure sintering evamile, i-microwave sintering iyindlela entsha ye-sintering, enezinzuzo zesikhathi esifushane se-sintering, ukusebenza kahle okuphezulu nokonga amandla, futhi ingathuthukisa i-microstructure yezitsha zobumba.

Ezinye izazi futhi zikholelwa ukuthi i-zirconia ngemuva kwe-microwave sintering ingagcina isigaba se-tequartet esine-metastable, mhlawumbe ngenxa yokuthi ukushisa okusheshayo kwe-microwave kungafinyelela ukuminyana okusheshayo kwezinto ezingeni lokushisa eliphansi, usayizi wokusanhlamvu mncane futhi ufana kakhulu kunalowo we-pressure sintering evamile, ephansi kune usayizi wokuguqulwa kwesigaba esibalulekile se-t-ZrO2, esiza ekugcineni ngangokunokwenzeka esimweni se-metastable ekamelweni lokushisa, ukuthuthukisa amandla kanye nokuqina kwezinto zobumba.

Inqubo ye-sintering kabili

I-compact sintered zirconia ceramics ingacutshungulwa kuphela ngamathuluzi okusika i-emery ngenxa yokuqina okukhulu namandla, futhi izindleko zokucubungula ziphezulu futhi isikhathi side. Ukuze uxazulule lezi zinkinga ezingenhla, ngezinye izikhathi i-zirconia ceramics izosetshenziswa kabili inqubo ye-sintering, ngemva kokwakhiwa komzimba we-ceramic kanye ne-sintering yokuqala, i-CAD/CAM amplification machining to shape oyifunayo, bese i-sintering to the final sintering temperature ukwenza. impahla iminyene ngokuphelele.

Kutholakala ukuthi izinqubo ezimbili ze-sintering zizoshintsha i-sintering kinetics ye-zirconia ceramics, futhi izoba nemiphumela ethile ku-sintering density, izakhiwo zemishini kanye ne-microstructure ye-zirconia ceramics. Izakhiwo zemishini yeceramics ye-zirconia egayiwe uma isiminyene ingcono kunaleyo eshiswe kabili. Amandla okugoba e-biaxial kanye nokuqina kokuphuka kweceramics ye-zirconia eshintshwayo ehlanganiswe uma ihlangene iphakeme kunaleyo efakwe kabili. Imodi yokuphuka ye-primary sintered zirconia ceramics i-transgranular/intergranular, futhi isiteleka sokuqhekeka siqondile. Imodi yokuphuka kwamaceramics e-zirconia ane-sintered kabili iwukuphuka kwe-intergranular, futhi inkambiso yokuqhekeka ihlukumeza kakhulu. Izici zemodi yokuqhekeka eyinhlanganisela zingcono kunemodi elula yokuphuka kwe-intergranular.

I-vacuum yokuhlanza

I-Zirconia kumele ifakwe endaweni ye-vacuum, inqubo yokucwilisa izokhiqiza inani elikhulu lama-bubbles, futhi endaweni ye-vacuum, ama-bubbles kulula ukuwakhipha esimweni esincibilikisiwe somzimba we-porcelain, athuthukise ukuminyana kwe-zirconia, ngaleyo ndlela andise i-semi-permeability kanye nezakhiwo zemishini ye-zirconia.

Izinga lokushisa

Enkambweni ye-sintering ye-zirconia, ukuze uthole ukusebenza okuhle nemiphumela elindelekile, izinga lokushisa eliphansi kufanele lamukelwe. Izinga lokushisa eliphezulu lenza izinga lokushisa langaphakathi le-zirconia lingalingani lapho lifinyelela izinga lokushisa lokugcina le-sintering, okuholela ekubonakaleni kwemifantu kanye nokwakheka kwama-pores. Imiphumela ibonisa ukuthi ngokunyuka kwezinga lokushisa, isikhathi se-crystallization yamakristalu e-zirconia sifinyezwa, igesi phakathi kwamakristalu ayikwazi ukukhishwa, futhi i-porosity ngaphakathi kwamakristalu e-zirconia yanda kancane. Ngokunyuka kwezinga lokushisa, inani elincane lesigaba se-crystal monoclinic liqala ukuba khona esigabeni se-tetragonal se-zirconia, esizothinta izakhiwo zemishini. Ngesikhathi esifanayo, ngokunyuka kwezinga lokushisa, okusanhlamvu kuzoba yi-polarized, okungukuthi, ukuhlalisana kwezinhlamvu ezinkulu nezincane kulula. Izinga lokushisa elihamba kancane livumela ukwakheka kwezinhlamvu eziningi ezifanayo, okwandisa i-semipermeability ye-zirconia.