1 Ukusetyenziswa kunye nenkqubela yophando lwe-silicon carbide coating kwizixhobo ze-carbon/carbon thermal field
1.1 Inkqubela phambili yokusetyenziswa kunye nophando ekulungiseleleni i-crucible
Kwintsimi yobushushu yekristale enye,i-carbon/carbon crucibleisetyenziswa kakhulu njengesitya sokuthwala izinto zesilicon kwaye idibana ne-isixhobo sokuqhumisa se-quartz, njengoko kubonisiwe kuMfanekiso 2. Ubushushu bokusebenza kwe-carbon/carbon crucible bumalunga ne-1450℃, nto leyo ebangela ukukhukuliseka kabini kwe-silicon eqinileyo (i-silicon dioxide) kunye nomphunga we-silicon, kwaye ekugqibeleni i-crucible iba ncinci okanye ibe ne-ring crack, nto leyo ebangela ukuba i-crucible ingasebenzi.
I-composite coating carbon/carbon composite crucible yalungiswa ngenkqubo yokugcwala komphunga weekhemikhali kunye ne-in-situ reaction. I-composite coating yayiqulathe i-silicon carbide coating (100~300μm), i-silicon coating (10~20μm) kunye ne-silicon nitride coating (50~100μm), enokuthintela ngempumelelo ukugqwala komphunga we-silicon kumphezulu wangaphakathi we-carbon/carbon composite crucible. Kwinkqubo yemveliso, ukulahleka kwe-composite coating carbon/carbon composite crucible yi-0.04 mm ngesithando ngasinye, kwaye ubomi benkonzo bunokufikelela amaxesha ali-180 esithandweni.
Abaphandi basebenzise indlela yokusabela ngamakhemikhali ukuvelisa i-silicon carbide coating efanayo phezu komphezulu we-carbon/carbon composite crucible phantsi kweemeko ezithile zobushushu kunye nokukhuselwa kwegesi ethwalayo, besebenzisa i-silicon dioxide kunye ne-silicon metal njengezinto eziluhlaza kwi-oven eshushu kakhulu. Iziphumo zibonisa ukuba unyango lobushushu obuphezulu aluphuculi nje kuphela ubunyulu kunye namandla e-sic coating, kodwa lukwaphucula kakhulu ukumelana nokuguguleka komphezulu we-carbon/carbon composite, kwaye luthintela ukugqwala komphezulu we-crucible yi-SiO2 umphunga kunye nee-athomu ze-oxygen eziguquguqukayo kwi-oven ye-silicon ye-monocrystal. Ubomi benkonzo ye-crucible bunyuswa ngama-20% xa kuthelekiswa nobo be-crucible ngaphandle kwe-sic coating.
1.2 Inkqubela yokusetyenziswa kunye nophando kwityhubhu yesikhokelo sokuhamba
Isilinda esikhokelayo sibekwe ngaphezulu kwe-crucible (njengoko kubonisiwe kuMfanekiso 1). Kwinkqubo yokutsala ikristale, umahluko wobushushu phakathi kwangaphakathi nangaphandle kwentsimi mkhulu, ingakumbi umphezulu ongaphantsi usondele kakhulu kwizinto ze-silicon ezinyibilikisiweyo, ubushushu buphezulu kakhulu, kwaye ukugqwala ngumphunga we-silicon yeyona nto imbi kakhulu.
Abaphandi bayile inkqubo elula kunye nokumelana okuhle kwe-oxidation yetyhubhu yesikhokelo kunye nendlela yokulungiselela i-anti-oxidation coating kunye ne-preparation. Okokuqala, umaleko we-silicon carbide whisker wakhuliswa kwindawo ethile kwi-matrix yetyhubhu yesikhokelo, kwaza kwalungiswa umaleko wangaphandle we-silicon carbide, ukuze kwenziwe umaleko we-SiCw transition phakathi kwe-matrix kunye nomaleko womphezulu we-silicon carbide, njengoko kubonisiwe kuMfanekiso 3. I-coefficient of thermal expansion yayiphakathi kwe-matrix kunye ne-silicon carbide. Inganciphisa ngempumelelo uxinzelelo lwe-thermal olubangelwa kukungalingani kwe-thermal expansion coefficient.
Uhlalutyo lubonisa ukuba ngokonyuka komxholo weSiCw, ubungakanani kunye nenani leemifantu kwi-coating liyancipha. Emva kwe-oxidation yeeyure ezili-10 emoyeni we-1100 ℃, izinga lokulahleka kobunzima besampuli ye-coating yi-0.87% ~ 8.87% kuphela, kwaye ukumelana ne-oxidation kunye nokumelana nobushushu kwe-silicon carbide coating kuphuculwe kakhulu. Inkqubo yonke yokulungiselela igqitywa ngokuqhubekayo ngokubeka umphunga weekhemikhali, ukulungiswa kwe-silicon carbide coating kwenziwa lula kakhulu, kwaye ukusebenza okubanzi kwe-nozzle yonke kuyaqiniswa.
Abaphandi bacebise indlela yokuqinisa i-matrix kunye nokwaleka komphezulu wetyhubhu yesikhokelo se-graphite kwi-silicon ye-czohr monocrystal. I-slurry ye-silicon carbide efunyenweyo yagqunywa ngokulinganayo kumphezulu wetyhubhu yesikhokelo se-graphite ngobukhulu be-30 ~ 50 μm ngebrashi yokugquma okanye indlela yokufutha, yaze yafakwa kwisithando sobushushu obuphezulu ukuze iphendule kwindawo yayo, ubushushu bokusabela babuyi-1850 ~ 2300 ℃, kwaye ukugcinwa kobushushu kwakuyi-2 ~ 6 h. Umaleko wangaphandle we-SiC ungasetyenziswa kwisithando sokukhulisa ikristale esinye esingama-24 in (60.96 cm), kwaye ubushushu bokusetyenziswa buyi-1500 ℃, kwaye kufunyaniswe ukuba akukho mgubo uqhekekayo nowayo kumphezulu wesilinda yesikhokelo se-graphite emva kwe-1500 h.
1.3 Inkqubela yokusetyenziswa kunye nophando kwisilinda yokukhusela ubushushu
Njengenye yezona zinto ziphambili kwinkqubo yentsimi yobushushu ye-silicon e-monocrystalline, isilinda yobushushu isetyenziselwa kakhulu ukunciphisa ukulahleka kobushushu kunye nokulawula i-gradient yobushushu yendawo yentsimi yobushushu. Njengenxalenye exhasayo yomaleko wobushushu bodonga lwangaphakathi lwe-single crystal furnace, i-silicon vapor corrosion ikhokelela ekuweni kwe-slag kunye nokuqhekeka kwemveliso, okuthi ekugqibeleni kukhokelela ekungasebenzini kwemveliso.
Ukuze kuphuculwe ngakumbi ukumelana nokugqwala komphunga we-silicon kwityhubhu yokugquma ye-C/C-sic composite, abaphandi bafake iimveliso zetyhubhu yokugquma ye-C/C-sic ezilungisiweyo kwisithando sokusabela komphunga wekhemikhali, baza balungisa i-dense silicon carbide coating phezu komphezulu weemveliso zetyhubhu yokugquma ye-C/C-sic composite ngenkqubo yokubeka umphunga wekhemikhali. Iziphumo zibonisa ukuba, Le nkqubo inokuthintela ngempumelelo ukugqwala kwe-carbon fiber embindini we-C/C-sic composite nge-silicon vapor, kwaye ukumelana nokugqwala komphunga we-silicon kunyuswa ngamaxesha ama-5 ukuya kwali-10 xa kuthelekiswa ne-carbon/carbon composite, kwaye ubomi benkonzo yesilinda yokugquma kunye nokhuseleko lwendawo yobushushu buphuculwe kakhulu.
2. Isiphelo kunye nethemba
Ugqubuthelo lwe-silicon carbideisetyenziswa kakhulu kwizixhobo zentsimi yobushushu bekhabhoni/khabhoni ngenxa yokumelana kwayo kakuhle ne-oxidation kubushushu obuphezulu. Ngenxa yokwanda kobukhulu bezixhobo zentsimi yobushushu bekhabhoni/khabhoni ezisetyenziswa kwimveliso ye-silicon ye-monocrystalline, indlela yokuphucula ukufana kwe-silicon carbide coating kumphezulu wezixhobo zentsimi yobushushu kunye nokuphucula ubomi benkonzo yezixhobo zentsimi yobushushu bekhabhoni/khabhoni ibe yingxaki engxamisekileyo ekufuneka isonjululwe.
Kwelinye icala, ngophuhliso lweshishini le-silicon eli-monocrystalline, imfuno yezinto ezishushu ze-carbon/carbon thermal field ezicocekileyo kakhulu nayo iyanda, kwaye ii-nanofibers ze-SiC nazo zikhuliswa kwiifayibha zekhabhoni zangaphakathi ngexesha lokusabela. Amazinga okukhupha ngobuninzi kunye namazinga okukhupha ngomgca we-C/ C-ZRC kunye nee-C/ C-sic ZrC composites ezilungiselelwe ngovavanyo yi--0.32 mg/s kunye ne-2.57 μm/s, ngokwahlukeneyo. Amazinga okukhupha ngobunzima kunye nomgca we-C/ C-sic -ZrC composites yi--0.24mg/s kunye ne-1.66 μm/s, ngokwahlukeneyo. Ii-composites ze-C/ C-ZRC ezinee-nanofibers ze-SiC zineempawu ezingcono zokukhupha ngobuninzi. Kamva, iziphumo zemithombo eyahlukeneyo yekhabhoni ekukhuleni kwee-nanofibers ze-SiC kunye nendlela yokusebenza kwee-nanofibers ze-SiC eziqinisa iimpawu zokukhupha ngobuninzi zee-composites ze-C/ C-ZRC ziya kufundwa.
I-composite coating carbon/carbon composite crucible yalungiswa ngenkqubo yokugcwala komphunga weekhemikhali kunye ne-in-situ reaction. I-composite coating yayiqulathe i-silicon carbide coating (100~300μm), i-silicon coating (10~20μm) kunye ne-silicon nitride coating (50~100μm), enokuthintela ngempumelelo ukugqwala komphunga we-silicon kumphezulu wangaphakathi we-carbon/carbon composite crucible. Kwinkqubo yemveliso, ukulahleka kwe-composite coating carbon/carbon composite crucible yi-0.04 mm ngesithando ngasinye, kwaye ubomi benkonzo bunokufikelela amaxesha ali-180 esithandweni.
Ixesha lokuthumela: Februwari-22-2024