Umxholo wekhabhoni we-sintered specimen fracture yahlukile, kunye nomxholo wekhabhoni we-A-2.5 awt.% kolu luhlu, ukwenza izinto ezixineneyo kunye neepores eziphantse zingabikho, eziqulunqwe ngamasuntswana e-silicon carbide ahanjiswe ngokufanayo kunye ne-silicon yamahhala. Ngokunyuka kwekhabhoni yokongezwa, umxholo we-react-sintered silicon carbide ukhula ngokuthe ngcembe, ubungakanani besuntswana le-silicon carbide buyanda, kwaye i-silicon carbide idityaniswe omnye komnye kwimilo ye-skeleton. Nangona kunjalo, umxholo wekhabhoni ogqithisileyo unokukhokelela ngokulula kwintsalela yekhabhoni kumzimba odibeneyo. Xa i-carbon black iphinde inyuke ibe yi-3a, i-sintering yesampuli ayiphelelanga, kwaye "i-interlayers" emnyama ibonakala ngaphakathi.
Xa i-carbon isabela nge-silicon etyhidiweyo, izinga lokwandiswa kwevolumu yi-234%, eyenza i-microstructure ye-reaction-sintered silicon carbide ngokusondeleyo kumxholo wekhabhoni kwi-billet. Xa umxholo wekhabhoni kwi-billet encinci, i-silicon carbide eyenziwa yi-silicon-carbon reaction ayanelanga ukuzalisa iipores ezijikeleze i-carbon powder, okubangelwa isixa esikhulu se-silicon yamahhala kwisampuli. Ngokunyuka komxholo wekhabhoni kwi-billet, i-react-sintered silicon carbide inokuzalisa ngokupheleleyo iipores ezijikeleze i-carbon powder kwaye idibanise i-silicon carbide kunye. Ngeli xesha, umxholo we-silicon yasimahla kwisampulu iyancipha kwaye ubuninzi bomzimba odibeneyo buyanda. Nangona kunjalo, xa kukho ikhabhoni eninzi kwi-billet, i-silicon carbide yesibini eyenziwa yimpendulo phakathi kwekhabhoni kunye ne-silicon ijikeleze ngokukhawuleza i-toner, isenza kube nzima kwi-silicon etyhidiweyo ukuba iqhagamshelane ne-toner, okukhokelela kwi-carbon eseleyo kumzimba odibeneyo.
Ngokweziphumo ze-XRD, ukubunjwa kwesigaba se-reaction-sintered sic yi-α-SiC, i-β-SiC kunye ne-silicon yamahhala.
Kwinkqubo yokushisa okuphezulu kwe-sintering, ii-athomu zekhabhoni zifudukela kwindawo yokuqala kwi-SiC surface β-SiC nge-silicon etyhidiweyo i-α-secondary formation. Ekubeni i-silicon-carbon reaction iyindlela eqhelekileyo yokusabela exothermic kunye nobushushu obukhulu bokusabela, ukupholisa ngokukhawuleza emva kwexesha elifutshane lokusabela kobushushu obuphezulu kwandisa ukuchithwa kwekhabhoni enyibilikisiweyo kwi-silicon yolwelo, ukwenzela ukuba amasuntswana e-β-SiC awele kwi-silicone. ifom yekhabhoni, ngaloo ndlela iphucula iimpawu zomatshini wezinto eziphathekayo. Ke ngoko, ukuphuculwa kwengqolowa ye-β-SiC yesibini kunenzuzo ekuphuculeni amandla okugoba. Kwinkqubo ehlanganisiweyo ye-Si-SiC, umxholo we-silicon yamahhala kwizinto eziphathekayo uyancipha ngokunyuka kwekhabhoni umxholo kwizinto eziluhlaza.
Isiphelo:
(1) I-viscosity ye-slurry esebenzayo esebenzayo esebenzayo iyanda ngokunyuka kobuninzi bekhabhoni emnyama; Ixabiso le-pH li-alkaline kwaye liyenyuka ngokuthe ngcembe.
(2) Ngokunyuka komxholo wekhabhoni emzimbeni, ukuxinana kunye namandla okugoba kwe-reaction-sintered ceramics elungiselelwe ngokucinezela indlela yokuqala yanda kwaye yanciphisa. Xa ubungakanani bekhabhoni emnyama ngamaxesha angama-2.5 exabiso lokuqala, amandla okugoba amanqaku amathathu kunye nobuninzi be-billet eluhlaza emva kokuphendula sintering ziphezulu kakhulu, eziyi-227.5mpa kunye ne-3.093g / cm3, ngokulandelanayo.
(3) Xa umzimba onekhabhoni eninzi ugxothiwe, iintanda kunye neendawo ezimnyama "zesandwich" ziya kuvela emzimbeni womzimba. Isizathu sokuqhekeka kukuba igesi ye-silicon oxide eyenziwe kwinkqubo yokuphendula i-sintering ayilula ukuyikhupha, ngokuthe ngcembe iqokelele, uxinzelelo luyenyuka, kwaye umphumo walo we-jacking ukhokelela ekuqhekekeni kwe-billet. Kwindawo emnyama "isandwich" ngaphakathi kwe-sinter, kukho inani elikhulu lekhabhoni elingabandakanyekanga ekuphenduleni.
Ixesha lokuposa: Jul-10-2023