Ukusabela okucasulayo
Ukusabela okucasulayoi-silicon carbide ceramicInqubo yokukhiqiza ifaka phakathi ukuhlanganiswa kwe-ceramic, ukuhlanganiswa kwe-sintering flux infiltration agent, ukulungiswa komkhiqizo we-ceramic okwenziwa nge-reaction sintering, ukulungiswa kwe-silicon carbide wood ceramic kanye nezinye izinyathelo.
I-nozzle ye-silicon carbide ephendulayo
Okokuqala, 80-90% wempuphu ye-ceramic (eyakhiwe yimpuphu eyodwa noma ezimbili ze-i-silicon carbide powderkanye ne-boron carbide powder), u-3-15% we-carbon source powder (owakhiwe yi-carbon black eyodwa noma ezimbili kanye ne-phenolic resin) kanye no-5-15% we-molding agent (i-phenolic resin, i-polyethylene glycol, i-hydroxymethyl cellulose noma i-paraffin) zixutshwa ngokulinganayo kusetshenziswa i-ball mill ukuthola i-mixed powder, eyomiswa nge-spray bese i-granulated, bese icindezelwa kwi-mold ukuze kutholakale i-ceramic compact enezinhlobo ezahlukene ezithile.
Okwesibili, i-60-80% yempuphu ye-silicon, i-3-10% yempuphu ye-silicon carbide kanye ne-37-10% yempuphu ye-boron nitride zixutshwa ngokulinganayo, bese zicindezelwa esikhumbeni ukuze zithole i-sintering flux infiltration agent compact.
I-ceramic compact kanye ne-sintered infiltrant compact zibe sezihlanganiswa ndawonye, bese izinga lokushisa liphakanyiswa libe ngu-1450-1750℃ esithandweni se-vacuum esinezinga le-vacuum elingaphansi kuka-5×10-1 Pa ukuze kuhlanzwe futhi kugcinwe ukushisa amahora angu-1-3 ukuze kutholakale umkhiqizo we-ceramic ohlanziwe. Insalela ye-infiltrant ebusweni be-ceramic ehlanziwe isuswa ngokuthepha ukuze kutholakale ishidi le-ceramic eliqinile, bese isimo sokuqala se-compact sigcinwa.
Ekugcineni, inqubo yokususa ukusabela iyamukelwa, okungukuthi, i-silicon ewuketshezi noma i-silicon alloy enomsebenzi wokusabela ekushiseni okuphezulu ingena ku-clamp ye-ceramic embozwe equkethe i-carbon ngaphansi kwesenzo samandla e-capillary, bese isabela ne-carbon ekuyo ukuze yakhe i-silicon carbide, ezokhula ngobuningi, bese ama-pores asele agcwala i-silicon eyisisekelo. I-clamp ye-ceramic embozwe embozwe ingaba yi-carbon emsulwa noma i-silicon carbide/i-carbon-based composite material. Eyokuqala itholakala ngokucubungula nge-catalytically kanye ne-pyrolyzing i-resin ephilayo, i-pore form kanye ne-solvent. Eyokugcina itholakala ngokucubungula izinhlayiya ze-silicon carbide/izinto ezihlanganisiwe ezisekelwe ku-resin ukuthola izinto ezihlanganisiwe ezisekelwe ku-silicon carbide/carbon, noma ngokusebenzisa i-α-SiC kanye ne-carbon powder njengezinto zokuqala nokusebenzisa inqubo yokucindezela noma yokujova ukuthola izinto ezihlanganisiwe.
Ukushisa okungenangcindezi
Inqubo yokusila engenangcindezi ye-silicon carbide ingahlukaniswa ibe yi-solid-phase sintering kanye ne-liquid-phase sintering. Eminyakeni yamuva nje, ucwaningo mayelanaizitsha zobumba ze-silicon carbideekhaya nakwamanye amazwe kugxile kakhulu ekushiseni okwenziwa ngesigaba soketshezi. Inqubo yokulungiselela i-ceramic yile: ukugaywa kwebhola okuxubile–>ukufutha nge-spray–>ukucindezela okomile–>ukuqina komzimba oluhlaza–>ukushisisa i-vacuum.
Imikhiqizo ye-silicon carbide engenangcindezi engenangcindezi
Engeza izingxenye ezingu-96-99 ze-silicon carbide ultrafine powder (50-500nm), izingxenye ezingu-1-2 ze-boron carbide ultrafine powder (50-500nm), izingxenye ezingu-0.2-1 ze-nano-titanium boride (30-80nm), izingxenye ezingu-10-20 ze-phenolic resin encibilikayo emanzini, kanye nezingxenye ezingu-0.1-0.5 ze-dispersant esebenza kahle kakhulu emshinini wokugaya ibhola ukuze kugaywe futhi kuxutshwe amahora angu-24, bese ufaka i-slurry exubile emgqonyeni wokuxuba ukuze uvuse amahora ama-2 ukuze ususe amabhamuza ku-slurry.
Ingxube engenhla ifuthwa embhoshongweni we-granulation, bese kuthi i-granulation powder enesimo esihle sezinhlayiya, ukugeleza okuhle, ububanzi bokusatshalaliswa kwezinhlayiya obuncane kanye nomswakama omaphakathi itholakala ngokulawula ingcindezi yokufutha, izinga lokushisa lokungena komoya, izinga lokushisa lokukhipha umoya kanye nosayizi wezinhlayiya zeshidi lokufutha. Ukuguqulwa kwemvamisa ye-centrifugal kungu-26-32, izinga lokushisa lokungena komoya lingu-250-280℃, izinga lokushisa lokukhipha umoya lingu-100-120℃, kanti ingcindezi yokungena kwe-slurry ingu-40-60.
Impuphu ye-granulation engenhla ifakwa ku-mold ye-carbide eqinisiwe ukuze icindezelwe ukuze kutholakale umzimba oluhlaza. Indlela yokucindezela ingcindezi eqondiswa ohlangothini ngalunye, kanti i-tonnage yengcindezi yethuluzi lomshini ingamathani ayi-150-200.
Umzimba oluhlaza ocindezelwe ufakwa kuhhavini owomisayo ukuze womiswe futhi uphole ukuze uthole umzimba oluhlaza oqinile kahle.
Umzimba oluhlaza ophilisiwe ngenhla ubekwa endaweniisitsha sokubethela se-graphitefuthi ihlelwe kahle futhi icocekile, bese kuthi i-graphite crucible enomzimba oluhlaza ibekwe esithandweni sokushisa okuphezulu se-vacuum sintering ukuze idutshulwe. Izinga lokushisa lokudubula lingu-2200-2250℃, kanti isikhathi sokushisa singamahora angu-1-2. Ekugcineni, kutholakala i-silicon carbide ceramics engenangcindezi eshisayo esebenza kahle kakhulu.
Ukushisa kwesigaba esiqinile
Inqubo yokusila engenangcindezi ye-silicon carbide ingahlukaniswa ibe yi-solid-phase sintering kanye ne-liquid-phase sintering. Ukusila kwe-liquid-phase kudinga ukungezwa kwezithasiselo zokusila, njengezithasiselo ze-Y2O3 binary kanye ne-ternary, ukuze i-SiC nezinto zayo ezihlanganisiwe ziveze i-liquid-phase sintering futhi zifinyelele ekuqineni ekushiseni okuphansi. Indlela yokulungiselela i-solid-phase sintered silicon carbide ceramics ifaka phakathi ukuxuba izinto zokusetshenziswa, i-spray granulation, i-molding, kanye ne-vacuum sintering. Inqubo ethile yokukhiqiza imi kanje:
Ama-70-90% e-submicron α silicon carbide (200-500nm), ama-0.1-5% e-boron carbide, ama-4-20% e-resin, kanye nama-5-20% e-organic binder afakwa ku-mixer bese engezwa ngamanzi ahlanzekile ukuze kuxutshwe ngamanzi. Ngemva kwamahora angu-6-48, i-slurry exubile idlula ngesihlungo se-mesh esingu-60-120;
I-slurry ehlungiwe ihlungiwe nge-spray ngokusebenzisa i-spray granulation tower. Izinga lokushisa lokungena lombhoshongo we-spray granulation lingu-180-260℃, kanti izinga lokushisa lokukhipha lingu-60-120℃; ubukhulu bezinto ezihlungiwe bungu-0.85-0.92g/cm3, ukugeleza kwamanzi kungu-8-11s/30g; izinto ezihlungiwe zihlungiwe ngesihlungo se-mesh esingu-60-120 ukuze zisetshenziswe kamuva;
Khetha isikhunta ngokwesimo somkhiqizo owufunayo, faka izinto ezigobile emgodini wesikhunta, bese wenza ukubumba kokucindezela kwegumbi ngokucindezela okungu-50-200MPa ukuze uthole umzimba oluhlaza; noma beka umzimba oluhlaza ngemva kokubumba kokucindezela kudivayisi yokucindezela oku-isostatic, yenza ukucindezela oku-isostatic ngokucindezela okungu-200-300MPa, bese uthola umzimba oluhlaza ngemva kokucindezela okwesibili;
Faka umzimba oluhlaza olungiselelwe ezinyathelweni ezingenhla esithandweni sokushisa esingenamthungo ukuze sishise, futhi ofanelekile yi-silicon carbide bulletproof ceramic eqediwe; enkambisweni yokushisa engenhla, qala ukhiphe isithando sokushisa esingenamthungo, futhi lapho izinga lokushisa lifinyelela ku-3-5 × 10-2 Ngemva kwe-Pa, igesi engasebenzi idluliselwa esithandweni sokushisa esingenamthungo ibe yingcindezi evamile bese ishiswa. Ubudlelwano phakathi kwezinga lokushisa lokushisa nesikhathi: izinga lokushisa legumbi kuya ku-800℃, amahora angu-5-8, ukugcinwa kokushisa ihora elingu-0.5-1, kusukela ku-800℃ kuya ku-2000-2300℃, amahora angu-6-9, ukugcinwa kokushisa ihora eli-1 kuya kwangu-2, bese upholiswa ngesithando bese wehliselwa ekushiseni kwegumbi.
Isakhiwo esincane kanye nomngcele wezinhlamvu ze-silicon carbide ezishisiwe ngengcindezi evamile
Ngamafuphi, izinto zobumba ezikhiqizwe ngenqubo yokusinta ngokucindezela okushisa zisebenza kangcono, kodwa izindleko zokukhiqiza nazo zikhushulwa kakhulu; izinto zobumba ezilungiselelwe ngokusinta ngaphandle kokucindezela zinezidingo eziphezulu zezinto zokusetshenziswa, izinga lokushisa eliphezulu lokusinta, izinguquko ezinkulu zosayizi womkhiqizo, inqubo eyinkimbinkimbi kanye nokusebenza okuphansi; imikhiqizo yobumba ekhiqizwe ngenqubo yokusinta yokusabela inobuningi obukhulu, ukusebenza okuhle kokulwa ne-ballistic, kanye nezindleko zokulungiselela eziphansi. Izinqubo ezahlukahlukene zokulungiselela ukusinta ze-silicon carbide ceramics zinezinzuzo nezinkinga zazo, futhi izimo zokusetshenziswa nazo zizohluka. Kuyinqubomgomo engcono kakhulu ukukhetha indlela efanele yokulungiselela ngokuya ngomkhiqizo bese uthola ibhalansi phakathi kwezindleko eziphansi kanye nokusebenza okuphezulu.
Isikhathi sokuthunyelwe: Okthoba-29-2024