falcelinta falcelinta
falcelinta falcelintadhoobada silikoon carbidehabka wax soo saarka waxaa ka mid ah isafgaradka dhoobada, is-afgarashada wakiilka qulqulka qulqulka, diyaarinta alaabta dhoobada falcelinta, diyaarinta dhoobada alwaax silikoon iyo tillaabooyin kale.
Dareenka falcelinta silikoon carbide nozzle
Marka hore, 80-90% budada dhoobada ah (oo ka kooban hal ama laba budo oo ahbudada carbide siliconiyo boron carbide budada), 3-15% budada isha kaarboon (oo ka kooban hal ama laba kaarboon madow iyo phenolic resin) iyo 5-15% ee wakiilka wax ka beddelka (resin phenolic, polyethylene glycol, hydroxymethyl cellulose ama paraffin) ayaa si siman loo walaaqayaa iyadoo la isticmaalayo mashiinka kubbadda si aad u hesho budo isku dhafan, taas oo la buufiyo oo la qalajiyey oo la dubay, ka dibna lagu cadaadiyo caaryada si loo helo isafgarad dhoobo ah oo leh qaabab kala duwan oo gaar ah.
Marka labaad, 60-80% budada silikon, 3-10% budada carbide silikoon iyo 37-10% budada boron nitride ayaa si isku mid ah loo qasaa, waxaana lagu cadaadiyaa caaryada si loo helo qulqulka qulqulka qulqulaya ee is haysta.
Isku-dhafka dhoobada iyo isafgaradka sintered ayaa markaa la isku dhejiyaa, heerkulku wuxuu kor u qaadayaa 1450-1750 ℃ foornada faakuumka leh oo leh heerka faakuum ee aan ka yarayn 5 × 10-1 Pa ee sintering iyo ilaalinta kulaylka 1-3 saacadood si aad u hesho wax soo saarka dhoobada sintered falcelinta. Hadhaaga soo-galootiga ee dusha sare ee dhoobada sintered ayaa laga saaraa iyadoo la taabanayo si loo helo xaashida dhoobada cufan, iyo qaabka asalka ah ee isafgaradka waa la ilaaliyaa.
Ugu dambeyntii, habka sintering dareen-celinta waa la ansixiyay, taas oo ah, silikoon dareere ah ama silikoon daawaha leh dhaqdhaqaaqa falcelinta heerkulka sare galay gudaha dhoobada dalool bannaan oo ka kooban kaarboon hoos ficil xoog capillary, oo la falgala kaarboon ku jira si ay u sameeyaan silicon carbide, kaas oo balaadhin doona mugga, iyo daloollada soo hadhay waxaa ka buuxa silikon elemental. Meesha bannaan ee dhoobada leh waxay noqon kartaa kaarboon saafi ah ama silikoon carbide/ walxo kaarboon ku salaysan. Midka hore waxaa lagu helaa iyadoo si firfircoon u daaweysa oo pyrolyzing resin organic ah, dalool hore iyo dareere. Midda dambe waxaa lagu helaa iyadoo la isticmaalayo pyrolying silikoon carbide particles/qalabka isku dhafan ee xabagta ku salaysan si loo helo silikoon carbide/kaarbon-ku-salaysan walxo isku dhafan, ama iyadoo la isticmaalayo α-SiC iyo budada kaarboon sidii qalab bilow ah iyo iyadoo la isticmaalayo habka qaabaynta tuubada ama duritaanka si loo helo isku dhafan maaddo.
Isku-dubbarid aan cadaadis lahayn
Geedi socodka sintering aan cadaadis lahayn ee silikon carbide waxa loo qaybin karaa sintering weji adag iyo dareere-wejiga sintering. Sanadihii la soo dhaafay, cilmi-baarista ku saabsandhoobada silikoon carbidegudaha iyo dibadda waxa ay inta badan diiradda saareen sintering wejiga dareeraha ah. Habka diyaarinta dhoobada ayaa ah: shiidista kubbadda walxaha isku dhafan-> buufiska granulation -> cadaadis qallalan -> adkaynta jidhka cagaarka -> vacuum sintering.
Alaabta carbide silikoon oo aan cadaadis lahayn
Ku dar 96-99 qaybood oo ah budada ultrafine silicon carbide (50-500nm), 1-2 qaybood oo boron carbide ultrafine budada ah (50-500nm), 0.2-1 qaybo nano-titanium boride (30-80nm), 10-20 qaybood oo ah resin phenolic biyo-milmi leh, iyo 0.1-0.5 qaybaha waxtarka sare leh ee kala firdhiya kubbadda kubbadda shiidista iyo qasinta 24 saacadood .
Isku darka kor ku xusan waxaa lagu buufiyaa munaaradda granulation, iyo budada granulation leh qaab-dhismeedka qayb wanaagsan, dheecaan wanaagsan, kala duwanaanta qaybinta qayb cidhiidhi ah iyo qoyaan dhexdhexaad ah ayaa la helay iyadoo la xakameynayo cadaadiska buufinta, heerkulka gelitaanka hawada, heerkulka hawada hawada iyo buufinta xajmiga qaybta. Beddelka inta jeer ee centrifugal waa 26-32, heerkulka gudaha hawadu waa 250-280 ℃, heerkulka hawada hawada waa 100-120 ℃, iyo cadaadiska gudaha slurry waa 40-60.
Budada granulation ee kore waxaa lagu dhejiyaa caaryada carbide sibidhka si loo cadaadiyo si loo helo jidh cagaaran. Habka cadaadisku waa cadaadiska labada dhinac, iyo cadaadiska qalabka mashiinka waa 150-200 tan.
Jirka cagaarka ah ee la riixay waxaa lagu dhejiyaa foornada qallajinta si loo engejiyo loona daweeyo si loo helo jir cagaaran oo leh xoog cagaar wanaagsan.
Jirka cagaarka ah ee kore ee la daweeyay waxa la dhigayaa agraphite crucibleoo loo habeeyey si dhow oo nadiif ah, ka dibna graphite crucible oo leh jidhka cagaaran ayaa la dhigayaa foorno nadiif ah oo heerkulka sare leh si loo toogto. Heerkulka dab-demiska waa 2200-2250 ℃, iyo waqtiga dahaarka waa 1-2 saacadood. Ugu dambeyntii, ceramics silikoon carbide sintered-waxqabadka sare cadaadiska lahayn ayaa la helay.
Waji adag oo sintayn
Geedi socodka sintering aan cadaadis lahayn ee silikon carbide waxa loo qaybin karaa sintering weji adag iyo dareere-wejiga sintering. Wajiga dareeraha ah wuxuu u baahan yahay in lagu daro waxyaabaha lagu daro, sida Y2O3 binary iyo ternary additives, si loo sameeyo SiC iyo agabkeeda isku dhafan ee soo bandhiga dareeraha-wajiga dareeraha ah oo lagu gaaro cufnaanta heerkul hoose. Habka diyaarinta ee ceramics silicon carbide sintered wejiga adag waxaa ka mid ah qaso alaabta ceeriin, granulation buufin, qaabaynta, iyo vacuum sintering. Habka wax soo saarka gaarka ah waa sida soo socota:
70-90% submicron α silicon carbide (200-500nm), 0.1-5% of boron carbide, 4-20% of resin, iyo 5-20% of binder organic waxaa lagu dhejiyaa qaso waxaana lagu daraa biyo saafi ah si qoyan isku dhafka. 6-48 saacadood ka dib, slurry isku dhafan ayaa la dhex maraa 60-120 shaandho mesh ah;
Biyo-mareenka la shaandheeyay waxa lagu buufiyaa granulated iyada oo la marayo munaaradda buufinta buufinta. Heerkulka galitaanka ee munaaradda granulation buufinta waa 180-260 ℃, iyo heerkulka dibadda waa 60-120 ℃; cufnaanta ugu badan ee walxaha granulated waa 0.85-0.92g / cm3, dareeraha waa 8-11s / 30g; Maaddada granulated waxaa lagu miiray iyada oo loo marayo 60-120 shaandho mesh ah si loo isticmaalo dambe;
Dooro caaryada si waafaqsan qaabka badeecada la rabo, ku shub walxaha granulated godka caaryada, oo samee qaabaynta heerkulka qolka cadaadiska 50-200MPa si aad u hesho jidh cagaaran; ama dhig jidhka cagaarka ah ka dib isku-buufinta isku-buufinta qalabka cadaadiska isostatic, samee cadaadiska isostatic ee cadaadiska 200-300MPa, oo hel jir cagaar ah ka dib cadaadiska labaad;
Geli jidhka cagaarka ah ee lagu diyaariyey tillaabooyinka kor ku xusan foornada vacuum sintering foorno si aad u sintering, iyo ka u qalma waa dhoobada ah silikoon carbide aan xabadu karin. habka sintering ee kor ku xusan, marka hore ka bax foornada sintering, iyo marka heerka faakuum gaaro 3-5 × 10-2 Pa ka dib, gaaska inert waxaa loo gudbiyaa foornada sintering cadaadiska caadiga ah ka dibna kuleyl. Xidhiidhka u dhexeeya kulaylka iyo wakhtiga waa: heerkulka qolka ilaa 800 ℃, 5-8 saacadood, ilaalinta kulaylka 0.5-1 saac, ka 800 ℃ in 2000-2300 ℃, 6-9 saacadood, ilaalinta kulaylka 1 ilaa 2 saacadood, ka dibna lagu qaboojiyey foornada oo hoos ugu dhig heerkulka qolka.
Qaab-dhismeed-yar iyo xadka hadhuudhka ee silikoon carbide ayaa ku sintay cadaadis caadi ah
Marka la soo koobo, ceramics-ka ay soo saarto habka kululaynta cadaadiska kulul waxay leeyihiin waxqabad wanaagsan, laakiin qiimaha wax soo saarka ayaa sidoo kale si weyn loo kordhiyaa; dhoobada ay diyaarisay sintering aan cadaadis lahayn ayaa leh shuruudaha alaabta ceeriin ee sarreeya, heerkulka sare ee heerkulka, isbeddelka cabbirka badeecada, habka adag iyo waxqabadka hooseeya; Alaabta dhoobada ah ee ay soo saarto habka falcelinta falcelinta waxay leeyihiin cufnaan sare, wax qabad fiican oo ka-hortagga kubbadda, iyo kharashka diyaarinta oo aad u hooseeya. Nidaamyada diyaarinta kala duwan ee diyaarinta dhoobada silikoon carbide ceramics waxay leeyihiin faa'iidooyin iyo faa'iidooyin iyaga u gaar ah, iyo xaaladaha codsiga sidoo kale way ka duwanaan doonaan. Waa siyaasadda ugu fiican in la doorto habka diyaarinta saxda ah iyadoo loo eegayo badeecada oo la helo dheelitirnaanta u dhexeeya qiimaha jaban iyo waxqabadka sare.
Waqtiga boostada: Oct-29-2024