Thaum tib neeg tham txog kev ploj tuag casting, lawv feem ntau obsess tshaj cov qauv siv quav ciab lossis cov hlau zaum kawg. Ceramic slurry yog dab tsi? Nws tau kho zoo li cov xim yooj yim, cov kauj ruam tom qab. Qhov ntawd yog thawj qhov yuam kev. Nyob rau hauv kev muaj tiag, lub slurry yog lub literal pwm-maker; nws tus cwj pwm dictates seb koj puas tau ib tug flawless casting los yog ib tug kim kim pawg. Nws tsis yog khoom. Ib pawg uas ua haujlwm rau cov hlau tsis muaj steel yuav ua tsis tau zoo rau cov txheej txheem nyias-walled nickel-based alloy. Kuv tau pom ntau lub khw, txawm tias muaj kev paub dhau los, kho nws raws li ib qho loj-haum-tag nrho cov khoom sib xyaw, tsuas yog ua rau lub ntsej muag lub plhaub tawg, suav nrog, lossis qhov txaus ntshai nto tiav, thiab tom qab ntawd cem cov dewaxing lossis lub cub tawg. Qhov tseeb feem ntau pib nrog lub tank slurry.
Nws yog Ntau tshaj li av nkos - Kev sib xyaw yog kev sib tham
Lub hauv paus yog yooj yim: refractory hmoov (xws li fused silica los yog zircon) thiab ib tug binder, feem ntau colloidal silica los yog ethyl silicate. Tab sis qhov yooj yim xaus rau ntawd. Lub particle loj faib ntawm cov hmoov nplej yog qhov tseem ceeb. Koj xav tau ib qho sib xyaw ntawm ntxhib thiab nplua nplej kom ua tiav qhov ntim kom zoo. Zoo heev, thiab koj yuav tau txais ntau qhov shrinkage thiab tawg thaum ziab thiab tua. Cov ntxhib dhau lawm, thiab koj qhov chaw tiav yuav ntxhib, poob tag nrho cov ntsiab lus uas koj tau ua haujlwm hnyav heev los ntes hauv cov quav ciab. Rau feem ntau ntawm peb ua hauj lwm nrog ceramic slurry rau poob ciab casting ntawm QSY, peb lean ntawm zircon-raws li system rau high-temperature alloys. Nws muaj ntau dua refractoriness, uas yog tsis-negotiable thaum koj nyob nraum pouring cobalt-raws li alloys uas qw tawm ntawm lub cub tawg.
Kev xaiv binder yog lwm qhov kev txiav txim hu. Colloidal silica yog cov neeg siv-phooj ywg, dej-raws li, tab sis nws tsim lub zog qeeb. Ethyl silicate ua rau lub plhaub muaj zog heev, tab sis nws yog cawv-raws li kev phom sij, kev tswj cov viscosity, thiab nws tuaj yeem ua rau lub plhaub nruj heev, ua rau cov kua muag kub hauv cov hlau. Peb siv ob qho tib si, tab sis rau qhov nyuaj, nyias ntu ntu hauv cov hlau lossis stainless, peb feem ntau mus nrog cov txheej txheem hybrid. Nws yog hais txog kev ntsuas lub zog ntsuab, lub zog hluav taws xob, thiab permeability. Tsis muaj phau ntawv teb; nws yog ib daim ntawv qhia koj kho raws li cov av noo nyob rau hauv lub rooj cob qhia hnub ntawd.
Tom qab ntawd muaj cov additives. Ob peb tee ntawm tus neeg sawv cev ntub dej los txo qhov nro ntawm qhov chaw kom cov slurry coats tus ciab tusyees, tshwj xeeb tshaj yog nyob rau ntawm qhov nyuaj hydrophobic nto. Lub defoamer yog qhov yuav tsum tau ua - cov npuas huab cua yog lub plhaub tsis xws luag tos kom tshwm sim. Qee zaum ib feem me me ntawm cov tshuaj tiv thaiv kab mob tshwj xeeb yog xav tau rau qee qhov geometries los tiv thaiv cov kab plaub hau hauv cov ceramic. Koj muab qhov no, thiab koj tsis cia li saib nws; koj xav tias. Lub viscosity yuav tsum tau coated koj ntiv tes nyob rau hauv ib txoj kev tshwj xeeb, tawm hauv ib tug txawm, opaque txheej. Peb xyuas nws nrog Zahn khob, tab sis cov neeg paub txog paub los ntawm txoj kev nws drips.
Dab ntxwg nyoog yog nyob rau hauv tus txheej txheem: Rheology thiab Tswj
Kev sib xyaw tsis yog tsuas yog pov cov khoom hauv lub tank. Nws yog kev tswj hwm, feem ntau qeeb, txheej txheem kom tsis txhob nplawm cua rau hauv qhov sib tov. Peb siv lub kiv cua sib tov nrog ib lub kaum ntse ntse. Tom qab sib tov, cov slurry yuav tsum muaj hnub nyoog-qee zaum 24 teev-rau chemistry kom ruaj khov. Nws rheology hloov. Ib qho kev sib xyaw tshiab slurry yuav ntws sai dhau los ntawm tsob ntoo siv quav ciab, tawm hauv lub tsho nyias nyias, tsis muaj zog. Ib tug neeg laus yuav muaj cov cuab yeej thixotropic zoo dua: nws ntws thaum ntxhov siab tab sis tuav nws cov duab thaum tseem, tsim ib txheej txheej.
Cov kev tswj tsis tau yog txhua hnub rituals. Qhov ntom ntom (los yog lub ntiajteb txawj nqus tshwj xeeb) raug kuaj xyuas kev ntseeg. Raws li dej evaporates, qhov ceev nce mus, thiab koj yuav tsum kho nws rov qab nrog dej distilled. Viscosity raug kuaj ua ntej txhua qhov kev hloov. pH tseem ceeb rau colloidal silica systems; Yog hais tias nws drifts, cov silica hais tuaj yeem pib gel ua ntej, ua rau tag nrho cov khoom puas. Kuv tau poob 500-liter tank ib zaug vim siv lub thoob tsis huv, hloov pH. Qhov ntawd yog ib zaj lus qhia kim heev hauv cov txheej txheem kev qhuab qhia. Koj tsis yog tuav cov kua dej xwb; koj nyob nraum tuav ib tug nyob, colloidal system.
Dipping cov khoom siv quav ciab yog ib qho txuj ci. Thawj lub tsho tiv no, lossis lub tsho tseem ceeb, yog qhov tseem ceeb tshaj plaws. Nws txhais cov nto tiav. Peb feem ntau siv cov hmoov nplej zoo ntawm no, qee zaum txawm ntxiv cov zircon zoo dua. Lub sij hawm ntws tawm, kev hloov ntawm tsob ntoo kom tsis txhob muaj kev sib txuam, ib puag ncig tiv thaiv plua plav-txhua yam tseem ceeb. Tom qab thawj lub tsho tiv no, peb tam sim ntawd thov stucco (coarse xuab zeb) thaum lub slurry tseem ntub. Tom qab ntawd nws yog lub voj voog: ziab, dipping, stuccoing, ziab. Kev ziab ib puag ncig (kub, av noo, airflow) yog qhov tseem ceeb raws li cov slurry nws tus kheej. Rushing qhov no ua rau cov plhaub ntsuab nrog cov khoom ntub dej, uas tig mus rau chav thiab tawg thaum dewaxing.
Case hauv Point: Ib qho Nickel-based Alloy Turbine Hniav
Qhov no yog qhov kev tshawb xav ntsib hluav taws. Peb muaj ib qhov project rau ib pawg me me ntawm nickel-based alloy turbine hniav. Cov qauv siv quav ciab tau zoo sib xws, nrog cov cua txias sab hauv. Thawj khiav siv peb cov qauv hlau alloy slurry mis. Qhov tshwm sim? Ob peb cov hniav pom cov kab nrib pleb zoo hauv cov npoo tom qab dewaxing hauv autoclave. Lub plhaub tau nruj heev thiab tsis tuaj yeem tiv taus qhov nrawm nrawm nrawm. Qhov tsis ua haujlwm yog nyob rau hauv slurry-binder system; nws muaj zog heev, nkig heev rau qhov geometry no.
Kev kho yog ib qho kev hloov kho ntau yam rau lub ceramic slurry rau poob ciab casting. Ua ntej, peb txo qis qhov sib piv me ntsis hauv thawj ob lub tsho tiv no kom tso cai rau me me kom yooj yim dua. Qhov thib ob, peb hloov lub stucco rau thawj lub tsho tiv no rau me ntsis angular, round-grained xuab zeb kom txo tau cov ntsiab lus kev ntxhov siab. Thib peb, peb txuas ntxiv lub sijhawm ziab ntawm cov tsho thawj zaug los ntawm 50%. Nws qeeb zuj zus lawm, tab sis nws ua haujlwm. Lub plhaub muaj zog txaus los tuav cov hlau tab sis txaus permeability thiab micro-muab kom ciaj sia dewaxing. Qhov kev daws teeb meem zoo li no yog tus qauv ntawm lub khw zoo li Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), qhov twg cov ntaub ntawv portfolio los ntawm cam khwb cia hlau rau tshwj xeeb alloys yuam kom koj hwm lub slurry raws li ib tug kuj sib txawv, tsis yog tas li.
Lwm qhov kev hloov maj mam: rau cov hlau kub kub no, lub plhaub yuav tsum tiv taus tsis yog qhov kub thiab txias, tab sis kuj tseem muaj cua sov ntev raws li qhov chaw loj loj casting solidifies maj mam. Ib qho slurry uas sinters lossis softens ntxov dhau tuaj yeem ua rau cov hlau nkag mus, tsim kom muaj qhov ntxhib, fused nto uas yog npau suav phem los ntxuav. Peb cov qauv zircon slurry, tsim ntau xyoo, yog tsim los tswj nws txoj kev ncaj ncees mus txog qhov txwv, uas yog vim li cas peb tuaj yeem ntseeg tau qhov xav tau specs rau cobalt thiab npib tsib xee-raws li qhov chaw.
Common Pitfalls thiab Xav Txog Nws
Tshaj li cov kev qhia tshwj xeeb, muaj qhov kev xav. Ib qho slurry uas tau siv ntau dhau los ua cov plua plav los ntawm stucco thiab hydrolyzed binder. Nws tau thicker, nws particle loj hloov. Koj tsis tuaj yeem cia li ntxiv dej los kho viscosity; uas dilutes cov ntsiab lus binder. Koj yuav tsum ua kom lub tank tsis tu ncua nrog cov slurry tshiab. Muaj qhov chaw qab zib hauv lub tank lub neej voj voog uas nws zoo kawg nkaus sib npaug - feem ntau tom qab ob peb lub voj voog tshiab.
Ib qho teeb meem tsis tu ncua yog slurry ntws tsim ib lub ledge los yog ib tug tuab buildup nyob rau hauv qab ntawm ib tug wax qauv. Qhov no tsim cov thermal loj sib txawv thaum lub sij hawm nchuav, ua rau shrinkage porosity nyob rau hauv cov hlau ntawm qhov chaw. Cov tshuaj tsis yog ib txwm nyob rau hauv slurry nws tus kheej, tab sis nyob rau hauv cov txheej txheem dipping - tej zaum koj yuav tsum tau dip, tig 180 degrees, thiab poob dua kom tau ib lub tsho tiv no. Nws yog kev kho txhais tes.
Thaum kawg, kev sib raug zoo ntawm cov slurry thiab tom qab tua. Lub plhaub yuav tsum raug rho tawm haujlwm kom hlawv tawm cov khoom seem thiab cov volatiles thiab txhim kho nws lub zog kawg. Yog tias cov mis slurry tawm, lub plhaub tuaj yeem tawg lossis tawg thaum tua. Peb ib txwm ua qhov kev sim tua ntawm lub plhaub los ntawm cov khoom tshiab lossis cov qauv ua ntej cog lus rau kev tsim khoom. Nws yog ib txoj cai pov hwm pheej yig. Lub plhaub raug rho tawm haujlwm yuav tsum muaj xim zoo ib yam thiab meej, resonant ping thaum tapping me ntsis. Lub suab ntxhib txhais tau hais tias muaj teeb meem-yuav muaj zog tsawg lossis micro-cracks.
Xaus: Lub Foundation yog txhua yam
Yog li, tom qab peb caug xyoo nyob rau hauv qhov kev ua si ntawm QSY, los ntawm plhaub pwm mus rau intricate peev casting, yog hais tias muaj ib yam rau rauj tsev, nws yog qhov no: tsis txhob underestimate lub slurry chav. Cov ceramic slurry rau poob ciab casting yog lub hauv paus kev cog lus ntawm cov qauv siv quav ciab thiab cov hlau molten. Nws yog ib qho dynamic, nyob rau hauv cov khoom siv uas xav tau kev hwm thiab kev soj ntsuam tas li. Koj tuaj yeem muaj cov quav ciab zoo tshaj plaws, kev tsim lub rooj vag zoo meej, thiab lub tshuab ua kom sov, tab sis cov slurry tswj tsis zoo yuav ua rau nws tag nrho. Nws tsis yog kev ua haujlwm zoo - nws feem ntau ntxhov thiab rov ua dua - tab sis qhov zoo ntawm txhua yam uas ua raws yog tsim, txheej los ntawm txheej, hauv lub tank. Qhov kev txawj ntse tiag tiag tsis yog hauv kev sib xyaw rau hauv daim ntawv spec; nws yog nyob rau hauv kev paub yuav ua li cas tweak nws rau ib feem ntawm tsob ntoo hnub no, rau lub alloy yog poured lub lim tiam tom ntej, thiab rau cov teeb meem koj daws tau tab sis tej zaum yuav pom dua nyob rau hauv ib tug txawv daim ntawv. Qhov ntawd yog cov khoom siv tes ua.
