Iiceramics ze-silicon carbide zinamandla aphezulu obushushu, ukumelana ne-oxidation yobushushu obuphezulu, ukumelana nokuguguleka okuhle, ukuzinza okuhle kobushushu, i-coefficient encinci yokwandiswa kobushushu, ukuqhuba okuphezulu kobushushu, ubunzima obuphezulu, ukumelana nobushushu, ukumelana nokugqwala kweekhemikhali kunye nezinye iimpawu ezintle. Isetyenziswe kakhulu kwiimoto, oomatshini, ukhuseleko lokusingqongileyo, ubuchwepheshe beenqwelo moya, i-elektroniki yolwazi, amandla kunye nezinye iindawo, kwaye iye yaba yiceramic yesakhiwo engenakutshintshwa enentsebenzo egqwesileyo kwiindawo ezininzi zoshishino. Ngoku mandikubonise!
Ukucoca ngaphandle koxinzelelo
Ukusila ngaphandle koxinzelelo kuthathwa njengeyona ndlela ithembisayo yokusila ngeSiC. Ngokweendlela ezahlukeneyo zokusila, ukusila ngaphandle koxinzelelo kunokwahlulwahlulwa kube kukusila ngesigaba esiqinileyo kunye nokusila ngesigaba solwelo. Ngokusebenzisa i-β- Encinci kakhulu. Isixa esifanelekileyo se-B kunye ne-C (umxholo weoksijini ongaphantsi kwe-2%) songezwa kumgubo weSiC ngaxeshanye, kwaye i-s. proehazka yasila emzimbeni osila ngeSiC onoxinano oluphezulu kune-98% ngo-2020 ℃. U-A. Mulla et al. Al2O3 kunye no-Y2O3 basetyenziswa njengezongezo kwaye basila nge-1850-1950 ℃ kwi-0.5 μ m β-SiC (umphezulu wamasuntswana uqulethe isixa esincinci seSiO2). Uxinano oluhambelanayo lweeseramikhi zeSiC ezifunyenweyo lukhulu kune-95% yoxinano lwethiyori, kwaye ubungakanani bengqolowa buncinci kwaye bubukhulu obuphakathi. Yi-1.5 microns.
Ukutshisa okushushu kwe-press
I-SiC ecocekileyo inokusikwa incinci kuphela kubushushu obuphezulu kakhulu ngaphandle kwezongezo zokusikwa, ngoko ke abantu abaninzi basebenzisa inkqubo yokusikwa kwe-SiC ngokucinezela ngobushushu. Kukho iingxelo ezininzi malunga nokusikwa kwe-SiC ngokucinezela ngobushushu ngokongeza izixhobo zokusikwa. U-Alliegro et al. Ufunde isiphumo se-boron, i-aluminium, i-nickel, i-iron, i-chromium kunye nezinye izongezo zesinyithi kwi-SiC densification. Iziphumo zibonisa ukuba i-aluminium kunye ne-iron zezona zongezo zisebenzayo ukukhuthaza ukusikwa kwe-SiC ngokucinezela ngobushushu. I-FFlange ifunde isiphumo sokongeza ubungakanani obahlukeneyo be-Al2O3 kwiipropati ze-SiC ecinezelwe ngobushushu. Kucingelwa ukuba ukuxinana kwe-SiC ecinezelwe ngobushushu kunxulumene nendlela yokunyibilika kunye nokuna kwemvula. Nangona kunjalo, inkqubo yokusikwa kwe-SiC ngokucinezela ngobushushu inokuvelisa kuphela iindawo ze-SiC ezinesimo esilula. Ubungakanani beemveliso eziveliswa yinkqubo yokusikwa kwe-SiC ngexesha elinye buncinci kakhulu, nto leyo engafanelekanga kwimveliso yemizi-mveliso.
Ukucofa okushushu kwe-isostatic
Ukuze koyiswe iziphene zenkqubo yesintu yokusila, uhlobo lwe-B kunye nohlobo lwe-C zasetyenziswa njengezongezo kwaye kwamkelwa iteknoloji yokusila eshushu ye-isostatic pressing. Kwi-1900 ° C, kwafunyanwa ii-ceramics ezintle zekristale ezinobunzima obungaphezulu kwe-98, kwaye amandla okugoba kubushushu begumbi anokufikelela kwi-600 MPa. Nangona ukusila eshushu ye-isostatic pressing kunokuvelisa iimveliso zesigaba esixineneyo ezineemilo ezintsonkothileyo kunye neempawu ezilungileyo zoomatshini, ukusila kufuneka kuvalwe, nto leyo enzima ukuyenza kwimveliso yemizi-mveliso.
Ukusabela okungalunganga
I-Reaction sintered silicon carbide, eyaziwa ngokuba yi-self bonded silicon carbide, ibhekisa kwinkqubo apho i-porous billet isabela khona ngegesi okanye i-liquid phase ukuphucula umgangatho we-billet, ukunciphisa i-porosity, kunye neemveliso ezigqityiweyo ze-sinter ngamandla athile kunye nokuchaneka okulinganayo. I-take α-SiC powder kunye ne-graphite zixutywa ngokwesilinganiso esithile kwaye zifudunyezwe ukuya kuthi ga kwi-1650 ℃ ukwenza i-square billet. Kwangaxeshanye, ingena okanye ingene kwi-billet nge-gaseous Si kwaye isabela ne-graphite ukwenza i-β-SiC, idityaniswe namasuntswana e-α-SiC akhoyo. Xa i-Si ingeniswe ngokupheleleyo, umzimba we-reaction sintered onobunzima obupheleleyo kunye nobukhulu obunganciphisi unokufumaneka. Xa kuthelekiswa nezinye iinkqubo ze-sintering, utshintsho lobungakanani be-reaction sintering kwinkqubo ye-densification luncinci, kwaye iimveliso ezinobukhulu obuchanekileyo zinokulungiswa. Nangona kunjalo, ukubakho kwenani elikhulu le-SiC emzimbeni we-sintered kwenza iipropati zobushushu obuphezulu ze-reaction sintered SiC ceramics zibe mbi ngakumbi.
Ixesha lokuthumela: Juni-08-2022