Kev xaiv ntawm silica sol txheej yuav cuam tshuam ncaj qha rau ntawm qhov chaw roughness thiab qhov tseeb qhov tseeb ntawmpeev castings. Silica sol coatings feem ntau tuaj yeem xaiv silica sol ncaj qha nrog ib feem ntawm silica ntawm 30%. Cov txheej txheem txheej yog yooj yim thiab kev ua haujlwm yooj yim. Nyob rau tib lub sijhawm, lub plhaub casting pwm tsim los ntawm kev siv txheej txheej muaj lub zog siab, thiab lub voj voog ua lub plhaub kuj tseem tuaj yeem ua kom luv.
Silica sol yog ib yam dej-raws li khi nrog ib tug silicic acid colloid qauv. Nws yog ib tug polymer colloidal tov nyob rau hauv uas heev dispersed silica hais yog soluble nyob rau hauv dej. Cov colloidal hais yog spherical thiab muaj ib txoj kab uas hla ntawm 6-100 nm. Covtxheej txheem ntawm peev castingua lub plhaub yog txheej txheem ntawm gelling. Muaj ntau yam cuam tshuam rau gelation, feem ntau yog electrolyte, pH, sol concentration thiab kub. Muaj ntau hom kev lag luam silica sols, thiab feem ntau siv yog alkaline silica sol nrog cov ntsiab lus silica ntawm 30%. Cov txheej txheem ntawm kev ua silica sol plhaub yog qhov yooj yim. Txhua txheej txheem muaj peb txheej txheem: txheej, xuab zeb, thiab ziab. Txhua tus txheej txheem yog rov ua ntau zaus kom tau txais lub plhaub multilayer ntawm qhov yuav tsum tau ua kom tuab.
Feem ntau muaj ob txoj hauv kev los tsim cov silica sol: ion pauv thiab tawg. Txoj kev sib pauv ion yog hais txog kev sib pauv ion ntawm diluted dej iav kom tshem tawm sodium ions thiab lwm yam impurities. Tom qab ntawd cov tshuaj yog lim, rhuab thiab concentrated rau ib tug tej yam ceev kom tau silica sol. Txoj kev sib cais yog hais txog kev siv cov khoom siv ntshiab silicon (qhov loj ntawm silicon ≥ 97%) raws li cov khoom siv raw, thiab nyob rau hauv qhov kev txiav txim ntawm cov catalyst, nws yog ncaj qha yaj hauv dej tom qab cua sov. Tom qab ntawd, cov tshuaj yog lim kom tau txais silica sol.
Technical Parameters ntawm Silica Sol rau Investment Casting | ||||||||
| Tsis muaj. | Chemical Composition (ntau feem pua, %) | Lub cev muaj zog | Lwm tus | |||||
| SiO 2 | Na2O | Qhov ceev (g / cm3) | pH | Kinematic Viscosity (mm2/s) | SiO2 Qhov Loj (nm) | Kev tshwm sim | Phase nyob ruaj ruaj | |
| 1 | 24–28 : kuv | ≤ 0.3 | 1.15-1.19 Nws | 9.0-9.5 Nws | ≤ 6 | 7–15 | nyob rau hauv invory los yog lub teeb ntsuab xim, tsis impurity | ≥ 1 xyoo |
| 2 | 29-31 : kuv | ≤ 0.5 | 1.20–1.22 dr hab | 9.0-10 Nws | ≤ 8 | 9–20 | ≥ 1 xyoo | |
Cov castings tau txais los ntawm silica sol plhaub ua cov txheej txheem muaj qhov roughness tsawg, qhov siab qhov tseeb thiab lub plhaub ntev ua lub voj voog. Cov txheej txheem no yog siv dav hauv casting high-temperature heat-resistant alloys, heat-resistant steels, stainless steels, carbon steels, low alloys, aluminium alloys and copper alloys.
Lub silica sol precision poob ciab peev casting txheej txheem yog tsim rau rov ua dua tshiab ntawm cov khoom sib txuas los ntawm ntau yam hlau sib txawv thiab kev ua haujlwm siab alloys. Txawm hais tias feem ntau yog siv rau cov me me castings, cov txheej txheem no tau siv los ua tiav qhov rooj dav hlau qhov rooj, nrog cov hlau castings txog li 500 kgs thiab aluminium castings txog li 50 kgs. Piv rau lwm cov txheej txheem casting xws li tuag casting lossis xuab zeb casting, nws tuaj yeem yog cov txheej txheem kim. Txawm li cas los xij, cov khoom uas tuaj yeem tsim tau siv peev casting tuaj yeem suav nrog cov duab sib txawv, thiab feem ntau cov khoom raug cam khwb cia nyob ze cov duab, yog li yuav tsum tau me me los yog tsis muaj rework ib zaug cam khwb cia.
Lub hauv paus ntsiab lus ntawm cov quav ciab txheej ntawm cov txheej txheem peev casting yog:
Nto txheej silica sol nplaum. Nws tuaj yeem ua kom lub zog ntawm txheej txheej thiab xyuas kom meej tias cov txheej txheej saum npoo tsis tawg;
Refractory. Nws yog feem ntau high-purity zirconium hmoov los xyuas kom meej tias cov txheej muaj txaus refractoriness thiab tsis chemically react nrog molten hlau.
Lubricant. Nws yog surfactant. Vim tias cov silica sol txheej yog txheej txheej dej, qhov ntub dej ntawm nws thiab cov pwm pwm tsis zoo, thiab cov txheej txheem thiab cov khoom dai tsis zoo. Yog li ntawd, nws yog ib qho tsim nyog yuav tau ntxiv tus neeg sawv cev ntub dej los txhim kho cov txheej txheem thiab kev ua haujlwm dai.
Defoamer. Nws kuj yog ib qho surfactant uas nws lub hom phiaj yog txhawm rau tshem tawm cov npuas npuas hauv tus neeg sawv cev ntub dej.
Cov nplej refiner. Nws tuaj yeem ua kom cov nplej ua kom zoo dua qub ntawm cov castings thiab txhim kho cov khoom siv ntawm cov hlau castings.
Lwm yam appendages:suspending agent, drying indicator, sustained release agent, lwm.
Kev xaiv kom raug ntawm qhov kev faib ua feem ntawm txhua feem hauv silica sol txheej yog tus yuam sij kom ntseeg tau qhov zoo ntawm txheej. Ob qho tseem ceeb tshaj plaws hauv cov txheej txheem yog refractories thiab binders. Qhov sib piv ntawm ob yog cov hmoov-rau-kua piv ntawm txheej txheej. Cov hmoov-rau-kua piv ntawm cov xim muaj txiaj ntsig zoo rau kev ua haujlwm ntawm cov xim thiab lub plhaub, uas yuav cuam tshuam rau qhov zoo ntawm cov casting. Yog hais tias cov hmoov-rau-kua piv ntawm cov txheej yog tsawg dhau, cov txheej yuav tsis ntom txaus thiab yuav muaj ntau qhov tsis muaj voids, uas yuav ua rau saum npoo ntawm cov casting ntxhib. Tsis tas li ntawd, qhov sib piv ntawm cov hmoov-rau-kua ntau dhau yuav ua rau muaj kev nyiam ntawm cov txheej txheej kom tawg, thiab lub plhaub lub zog yuav qis, uas yuav ua rau kom cov hlau molten thaum lub sij hawm casting. Ntawm qhov tod tes, yog tias cov hmoov-rau-kua piv yog siab dhau lawm, cov txheej yuav tuab heev thiab cov kua dej yuav tsis zoo, ua rau nws nyuaj rau kev tau txais txheej txheej nrog cov tuab tuab thiab tsim nyog.
Kev npaj txheej yog ib feem tseem ceeb ntawm kev ua kom zoo ntawm lub plhaub. Thaum tsim cov txheej txheem, cov khoom yuav tsum sib npaug sib npaug thiab sib xyaw ua ke thiab sib xyaw ua ke. Cov cuab yeej siv rau kev tsim cov xim, tus naj npawb ntawm qhov sib ntxiv thiab lub sijhawm nplawm txhua yam yuav cuam tshuam rau qhov zoo ntawm cov xim. Peb lub tuam txhab peev casting siv cov khoom sib txuas txuas ntxiv. Txhawm rau kom ntseeg tau tias cov txheej txheem zoo, thaum tag nrho cov khoom ntawm cov txheej yog cov khoom siv tshiab tshiab, cov txheej yuav tsum tau nplawm kom ntev txaus.
Kev tswj cov khoom ntawm silica sol coatings yog ib qho tseem ceeb ntawm kev tswj xyuas cov kauj ruam. Lub viscosity, ntom, ambient kub, thiab lwm yam ntawm cov xim yuav tsum tau ntsuas tsawg kawg peb zaug ib hnub twg, thiab yuav tsum tau tswj nyob rau hauv lub teeb ntau ntawm lub sij hawm.
Post lub sij hawm: Lub Xya hli ntuj-25-2022