Eminye imfucuza yezimboni ibonakala iwusizo ekukhiqizeni izitsha zobumba ze-mullite. Lezi zimfucumfucu zezimboni zicebile ngama-oxide ensimbi athile njenge-silica (SiO2) ne-alumina (Al2O3). Lokhu kunikeza imfucuza amandla okusetshenziswa njengomthombo wokuqala wezinto ezisetshenziswayo zokulungiselela izitsha zobumba ze-mullite. Inhloso yaleli phepha lokubuyekeza ukuhlanganisa nokubuyekeza izindlela ezahlukene zokulungisa izitsha zobumba ezisebenzise imfucuza yezimboni njengezinto zokuqala. Lokhu kubuyekezwa kuphinde kuchaze amazinga okushisa e-sintering kanye nezithasiselo zamakhemikhali ezisetshenziswa ekulungiseleleni kanye nemiphumela yako. Ukuqhathaniswa kwakho kokubili amandla emishini kanye nokwanda okushisayo kwezitsha zobumba ezibikiwe ze-mullite ezilungiswe ngemfucuza eyahlukene yezimboni nakho kwabhekwana nayo kulo msebenzi.
I-Mullite, evamise ukuchazwa ngokuthi 3Al2O3∙2SiO2, iwumsebenzi wobumba omuhle kakhulu ngenxa yezakhiwo zayo ezingavamile. Inephuzu lokuncibilika eliphezulu, i-coefficient ephansi yokwanda okushisayo, amandla aphezulu emazingeni okushisa aphezulu, futhi inokubili ukushaqeka okushisayo nokumelana nokukhasa [1]. Lezi zakhiwo ezingajwayelekile ezishisayo nezemishini zivumela okokusebenza ukuthi kusetshenziswe ezintweni ezinjengama-refractories, ifenisha yomlilo, ama-substrates ama-catalytic converters, amashubhu esithandweni somlilo, nezihlangu zokushisa.
I-Mullite ingatholakala kuphela njengamaminerali ayivelakancane e-Mull Island, eScotland [2]. Ngenxa yobukhona bayo obungavamile emvelweni, zonke izitsha zobumba ze-mullite ezisetshenziswa embonini zenziwe umuntu. Ucwaningo oluningi selwenziwe ukulungisa izitsha zobumba ze-mullite kusetshenziswa izandulela ezihlukene, kusukela kumakhemikhali ebanga lezimboni/selabhorethri [3] noma amaminerali e-aluminosilicate avela ngokwemvelo [4]. Kodwa-ke, izindleko zalezi zinto zokuqala ziyabiza, ezihlanganiswa noma zembiwa ngaphambili. Sekuyiminyaka, abacwaningi befuna ezinye izindlela zomnotho zokuhlanganisa i-mullite ceramics. Ngakho, izandulela eziningi ze-mullite ezithathwe emfucumfucwini yezimboni ziye zabikwa ezincwadini. Le mfucumfucu yezimboni inokuqukethwe okuphezulu kwe-silica ne-alumina ewusizo, okuyizinhlanganisela zamakhemikhali ezibalulekile ezidingekayo ukuze kukhiqizwe izitsha zobumba ze-mullite. Ezinye izinzuzo zokusebenzisa le mfucumfucu yasezimbonini ukonga amandla kanye nezindleko uma udoti uphambukisiwe waphinde wasetshenziswa njengempahla yobunjiniyela. Ngaphezu kwalokho, lokhu kungasiza futhi ekwehliseni umthwalo wemvelo futhi kuthuthukise inzuzo yayo kwezomnotho.
Ukuze kuphenywe ukuthi ingabe udoti omsulwa we-electroceramics ungasetshenziswa yini ukwenza izinto zobumba ze-mullite, imfucumfucu ehlanzekile ye-electroceramics exutshwe nezimpushana ze-alumina kanye nemfucuza emsulwa ye-electroceramics njengezinto zokusetshenziswa kuqhathaniswe. Izakhiwo ze-mullite ceramic zaphenywa. I-XRD ne-SEM yasetshenziselwa ukutadisha ukwakheka kwesigaba kanye ne-microstructure.
Imiphumela ibonisa ukuthi okuqukethwe kwe-mullite kuyanda ngokukhuphula izinga lokushisa le-sintering, futhi ngesikhathi esifanayo ukuminyana kwenqwaba kuyenyuka. Izinto zokusetshenziswa ziyimfucuza ye-electroceramics ehlanzekile, ngakho-ke umsebenzi we-sintering mkhulu, futhi inqubo ye-sintering ingasheshiswa, futhi ukuminyana kuyanda. Lapho i-mullite ilungiswa kuphela yimfucuza ye-electroceramics, ukuminyana kwenqwaba namandla acindezelayo kukhulu, i-porosity incane kakhulu, futhi izici ezibonakalayo eziphelele zizoba ngcono kakhulu.
Iqhutshwa isidingo sezinye izindlela ezingabizi kakhulu nezinobungani nemvelo, imizamo eminingi yocwaningo isebenzise imfucumfucu yezimboni njengezinto zokuqala ukukhiqiza izitsha zobumba ze-mullite. Izindlela zokucubungula, amazinga okushisa e-sintering, nezithasiselo zamakhemikhali zibuyekeziwe. Indlela yendabuko yokucubungula umzila ebandakanya ukuxuba, ukucindezela, kanye nokusabela kwe-sintering ye-mullite precursor bekuyindlela evame ukusetshenziswa kakhulu ngenxa yobulula bayo kanye nokusebenza kahle kwezindleko. Nakuba le ndlela ikwazi ukukhiqiza izitsha zobumba ze-mullite ezinama-porous, ama-porosity avela ku-mullite ceramic kubikwa ukuthi ahlala ngaphansi kwama-50%. Ngakolunye uhlangothi, ukulingisa kweqhwa kuboniswe ukuthi kukwazi ukukhiqiza i-mullite ceramic enezimbotshana ezimbotshana kakhulu, ene-porosity esobala engu-67%, ngisho nasezingeni eliphezulu kakhulu lokushisa elingu-1500 °C. Ukubuyekezwa kwamazinga okushisa e-sintering kanye nezithasiselo zamakhemikhali ezahlukene ezisetshenziswa ekukhiqizeni i-mullite kwenziwa. Kuyafiseleka ukusebenzisa izinga lokushisa elishisayo elingaphezu kuka-1500 °C ekukhiqizeni i-mullite, ngenxa yezinga eliphezulu lokusabela phakathi kwe-Al2O3 ne-SiO2 kwesandulela. Kodwa-ke, okuqukethwe kwe-silica okweqile okuhlotshaniswa nokungcola kwesandulela kungaholela ekwakhiweni kwesampula noma ekuncibilikeni phakathi ne-high-temperature sintering. Ngokuqondene nezithasiselo zamakhemikhali, i-CaF2, H3BO3, Na2SO4, TiO2, AlF3, ne-MoO3 kubikwe njengosizo olusebenzayo ekwehliseni izinga lokushisa le-sintering kuyilapho i-V2O5, i-Y2O3-doped ZrO2 kanye ne-3Y-PSZ ingasetshenziswa ukukhuthaza ukuminyana kwezitsha zobumba ze-mullite. Ukusebenzisa izithasiselo zamakhemikhali ezifana ne-AlF3, Na2SO4, NaH2PO4 · 2H2O, V2O5, ne-MgO kusize ukukhula kwe-anisotropic yamadevu e-mullite, okwathi kamuva kwathuthukisa amandla omzimba kanye nokuqina kwezitsha zobumba ze-mullite.
Isikhathi sokuthumela: Aug-29-2023