Okuqukethwe kwekhabhoni kokuqhekeka kwesampula ngayinye ye-sintered kuhlukile, kunokuqukethwe kwekhabhoni okungu-A-2.5 awt.% kulobu bubanzi, kwakha into eminyene ecishe ingabi nazimbotshana, eyakhiwe izinhlayiya ezisatshalaliswe ngokulinganayo ze-silicon carbide kanye ne-silicon yamahhala. Ngokukhula kokungezwa kwekhabhoni, okuqukethwe kwe-react-sintered silicon carbide kukhuphuka kancane kancane, usayizi wezinhlayiyana ze-silicon carbide uyakhula, futhi i-silicon carbide ixhunywe komunye nomunye ngendlela yohlaka lwamathambo. Kodwa-ke, okuqukethwe kwekhabhoni okweqile kungaholela kalula ekushiyeni kwekhabhoni emzimbeni onesinki. Uma i-carbon black iphinde ikhuphuke ibe ngu-3a, ukucwiliswa kwesampula akuphelele, futhi "ama-interlayers" amnyama avela ngaphakathi.
Lapho i-carbon iphendula nge-silicon encibilikisiwe, izinga layo lokunwetshwa kwevolumu lingama-234%, okwenza i-microstructure ye-react-sintered silicon carbide ihlobane eduze nokuqukethwe kwekhabhoni ku-billet. Lapho okuqukethwe kwekhabhoni ku-billet kukuncane, i-silicon carbide ekhiqizwa ukusabela kwe-silicon-carbon ayanele ukugcwalisa ama-pores azungeze i-carbon powder, okuholela ekutheni kube nenani elikhulu le-silicon yamahhala kusampula. Ngokukhula kokuqukethwe kwekhabhoni ku-billet, i-silicon carbide esabelayo ingagcwalisa ngokugcwele izimbotshana ezizungeze i-carbon powder futhi ixhume i-silicon carbide yasekuqaleni ndawonye. Ngalesi sikhathi, okuqukethwe kwe-silicon yamahhala kusampula kuyehla futhi ukuminyana komzimba we-sintered kuyanda. Kodwa-ke, uma kunekhabhoni eningi ku-billet, i-silicon carbide yesibili ekhiqizwa ukusabela phakathi kwekhabhoni ne-silicon izungeza ngokushesha i-toner, okwenza kube nzima nge-silicon encibilikisiwe ukuthi ixhumane ne-toner, okuholela ekuseleni kwekhabhoni emzimbeni one-sintered.
Ngokusho kwemiphumela ye-XRD, ukubunjwa kwesigaba se-reaction-sintered sic yi-α-SiC, i-β-SiC ne-silicon yamahhala.
Enqubweni yokusabela kwezinga lokushisa eliphezulu, ama-athomu ekhabhoni athuthela endaweni yokuqala endaweni ye-SiC engu-β-SiC ngokwakhiwa kwe-silicon encibilikisiwe α-secondary. Njengoba ukusabela kwe-silicon-carbon kuwukusabela okujwayelekile kwe-exothermic enenani elikhulu lokushisa okusabelayo, ukupholisa ngokushesha ngemva kwesikhathi esifushane sokusabela okuzenzakalelayo kokushisa okuphezulu kwandisa ukuthuthwa kwekhabhoni encibilike ku-silicon ewuketshezi, ukuze izinhlayiya ze-β-SiC zigibele ifomu le-carbon, ngaleyo ndlela ithuthukise izakhiwo zemishini yezinto ezibonakalayo. Ngakho-ke, ukucolisiswa okusanhlamvu kwesibili kwe-β-SiC kunenzuzo ekuthuthukiseni amandla okugoba. Kuhlelo oluyinhlanganisela ye-Si-SiC, okuqukethwe kwe-silicon yamahhala kokubalulekile kuncipha ngokwanda kokuqukethwe kwekhabhoni kumpahla eluhlaza.
Isiphetho:
(1) I-viscosity ye-sintering slurry elungisiwe esebenzayo iyanda ngokukhula kwenani le-carbon black; Inani le-pH liyi-alkaline futhi liyakhula kancane kancane.
(2) Ngokukhula kokuqukethwe kwekhabhoni emzimbeni, ukuminyana namandla okugoba e-reaction-sintered ceramics elungiswe ngendlela yokucindezela kuqala kwanda kwase kwehla. Uma inani le-carbon black liyizikhathi ezingu-2.5 yenani lokuqala, amandla okugoba amaphuzu amathathu kanye nokuminyana kwenqwaba ye-billet eluhlaza ngemva kokusabela sintering kuphezulu kakhulu, okungu-227.5mpa kanye no-3.093g/cm3, ngokulandelana.
(3) Lapho umzimba onekhabhoni eningi ushiswa, imifantu nezindawo “zesemishi” ezimnyama zizovela emzimbeni womzimba. Isizathu sokuqhekeka ukuthi igesi ye-silicon oxide ekhiqizwa inqubo yokuphendula i-sintering akulula ukuyikhipha, kancane kancane iqongelela, ingcindezi iphakama, futhi umphumela wayo we-jacking uholela ekuqhekekeni kwe-billet. Endaweni emnyama "yesemishi" ngaphakathi kwe-sinter, kunenani elikhulu lekhabhoni elingabandakanyeki ekuphenduleni.
Isikhathi sokuthumela: Jul-10-2023