Cov hlau yog cov khoom siv dav siv hauv ntau yam kev lag luam los ntawm kev tsim kho mus rau kev tsim khoom. Txawm li cas los xij, ntau tus neeg xav tias cov hlau yog ntxeem tau. Hauv tsab xov xwm no, peb tham txog dab tsi porosity yog dab tsi, nws cuam tshuam rau cov hlau, thiab teb qee cov lus nug nquag nug txog porosity hauv cov hlau.
Dab tsi yog porosity?
Porosity yog ib qho kev ntsuas ntawm qhov chaw tsis muaj dab tsi (pores) hauv cov khoom. Nws yog qhov sib piv ntawm qhov ntim ntawm qhov chaw tsis muaj dab tsi rau tag nrho cov ntim ntawm cov khoom. Porosity cuam tshuam rau lub cev thiab lub zog ntawm cov khoom siv xws li ceev, lub zog thiab permeability.
Muaj ntau hom Porosity, suav nrog:
Kaw Porosity:Voids uas tsis txuas rau saum npoo ntawm cov khoom.
Qhib porosity:Cov voids txuas rau saum npoo ntawm cov khoom.
Los ntawm Porosity:Cov voids txuas rau ob qhov chaw ntawm cov khoom siv.
Qee qhov piv txwv ntawm cov ntaub ntawv ntxeem tau yog sponges, ntawv, thiab ua npuas ncauj, thaum cov ntaub ntawv tsis ntxeem tau muaj xws li iav, ceramics, thiab qee cov hlau.
Porous txhais li cas?
Porous yog ib qho lus piav qhia txog cov khoom uas muaj qhov tsis muaj dab tsi lossis qhov pores uas tso cai rau cov kua dej los yog cov pa nkag mus rau hauv nws. Hauv lwm lo lus, nws hais txog lub peev xwm ntawm cov khoom siv los nqus lossiscia cov khoom hla dhau. Cov ntaub ntawv ntxeem tau muaj thaj chaw siab thiab siv ntau yam kev siv xws li pom, rwb thaiv tsev thiab nqus.
Piv txwv ntawm cov khoom ntxeem tau thiab tsis-porous
1. Qee qhov piv txwv ntawm cov khoom ntxeem tau yog:
daim txhuam cev
av
ntoo
Ua npuas ncauj
Ntawv
hluav taws kub
2. Qee qhov piv txwv ntawm cov khoom tsis yog porous yog:
iav
ceramics
Qee cov hlau (xws li kub, nyiaj, thiab platinum)
yas (nyob ntawm hom)
Porosity hauv cov hlau
Cov hlau tej zaum yuav ntxeem tau vim yog cov txheej txheem tsim khoom lossis npaj siv. Cov hlau ntxeem tau tuaj yeem muaj cov khoom xws li thaj chaw saum npoo av, txhim kho thermal thiab hluav taws xob conductivity, thiab txhim kho lub peev xwm pom.
Piv txwv li, stainless hlau tej zaum yuav ntxeem tau vim muaj cov welds los yog tsim ntawm corrosion. Aluminium kuj tuaj yeem ntxeem tau vim tsim cov oxide txheej lossis impurities hauv cov hlau. Hlau tej zaum yuav ntxeem tau vim nws cov txheej txheem tsim los yog raug rau corrosive ib puag ncig.
Kev kuaj rau Porosity hauv cov hlau
Txhawm rau txiav txim siab qhov porosity ntawm cov hlau, ntau txoj kev siv tau, xws li:
Metallographic tsom xam:Qhov no suav nrog kev siv lub microscope los tshuaj xyuas cov qauv ntawm cov hlau.
Xov tooj cua:Qhov no suav nrog kev nthuav tawm cov hlau rau X-rays kom pom cov voids sab hauv.
Kev kuaj ultrasonic:Qhov no suav nrog kev siv cov suab nrov nrov los xyuas cov voids sab hauv.
Gas pycnometric txoj kev:Qhov no suav nrog ntsuas qhov ntim ntawm cov pa tawm los ntawm cov khoom siv.
Txhua txoj kev muaj nws qhov zoo thiab qhov tsis zoo thiab tuaj yeem xaiv raws li qhov xav tau ntawm daim ntawv thov.
Porous Hlau Daim Ntawv Thov
Porous hlau yog siv ntau yam kev siv thoob plaws hauv kev lag luam, suav nrog:
Automotive:Siv nyob rau hauv cov roj txhaj tshuab, cua lim thiab tso cua tshuab.
Kev kho mob:Rau kev cog hniav, kev cog hniav thiab cov cuab yeej phais.
Electronics:Rau cov cua kub dab dej thiab electromagnetic shielding.
Aerospace:Rau cov roj tso tsheb hlau luam, cov cua kub sib txawv thiab cov lim dej.
Kev tsim kho:Rau acoustic panels thiab facade cladding.
Qee qhov nrov tshaj plaws nthuav dav hlau cov khoom lag luam muaj xws li nthuav cov ntawv hlau,
nthuav dav hlau raj, nthuav aluminium ntawv, nthuav aluminium ntawv, thiab nthuav hlau ua npuas ncauj.
Yuav Ua Li Cas Tiv Thaiv Pores hauv Hlau
Blowholes tuaj yeem tiv thaiv los ntawm kev siv cov kev ntsuas hauv qab no:
Kev xaiv zoo ntawm cov khoom siv raw thiab alloys.
Kev npaj kom zoo ntawm cov hlau nto ua ntej vuam los yog sib koom.
Tsim nyog vuam lossis koom nrog cov txheej txheem thiab cov kev txwv.
Siv cov tshuaj tiv thaiv los yog flux.
Txo qhov raug corrosive ib puag ncig.
Los ntawm kev siv cov kev ntsuas no, kev tsim cov voids hauv cov hlau tuaj yeem txo qis, ua rau cov khoom siv hlau muaj zog thiab txhim khu kev qha.
Puas yog stainless hlau ntxeem tau?
Stainless hlau feem ntau tsis suav hais tias yog cov khoom ntxeem tau hauv cov lus ib txwm muaj vim tias nws tsis tso cai rau cov khoom nkag mus tau yooj yim. Txawm li cas los xij, nws yog ib qho tseem ceeb uas yuav tsum nco ntsoov tias cov hlau tsis huv tuaj yeem hloov kho kom lawv cov ntxeem tau ntau dua los yog tsawg dua, nyob ntawm cov txheej txheem tshwj xeeb siv. Piv txwv li, ib tug polished stainless hlau nto yog tsawg ntxeem tau tshaj ib tug txhuam los yog sandblasted nto. Tsis tas li ntawd, yog tias cov hlau tsis muaj steel nto puas los yog khawb, nws yuav corrode yooj yim dua thiab yuav tso cai rau cov khoom nkag mus tau yooj yim dua.
Puas yog Aluminium Porous?
Aluminium feem ntau suav hais tias yog cov hlau ntxeem tau vim nws tuaj yeem nqus tau cov kua thiab cov pa hauv nws qhov chaw. Qhov no yog vim lub fact tias txhuas ib txwm tsim ib txheej nyias ntawm oxide ntawm nws nto, uas tsim me me pores los ntawm cov tshuaj yuav kis tau. Txawm li cas los xij, qhov ntsuas ntawm qhov porosity tuaj yeem sib txawv nyob ntawm seb muaj pes tsawg leeg ntawm aluminium alloy, qhov chaw tiav, thiab cov txheej txheem los yog kev kho mob siv rau saum npoo. Qee zaum, txhuas tuaj yeem txo qhov porosity los ntawm cov txheej txheem xws li anodizing lossis txheej nrog sealant.
Puas yog Steel Porous?
Zoo ib yam li stainless hlau, hlau tsis yog feem ntau suav hais tias yog cov khoom ntxeem tau hauv cov kev xav ib txwm muaj. Txawm li cas los xij, qhov porosity ntawm cov hlau tuaj yeem nyob ntawm ntau yam, xws li hom tshwj xeeb ntawm cov hlau, qhov chaw tiav, thiab cov txheej txheem los yog kev kho mob siv rau saum npoo. Piv txwv li, qee hom hlau yuav muaj cov qauv qhib ntau dua thiab muaj kev cuam tshuam ntau dua rau corrosion los yog xeb, uas tuaj yeem ua rau muaj qhov pores lossis kab noj hniav nyob rau lub sijhawm. Tsis tas li ntawd, yog tias qhov saum npoo ntawm cov hlau tsis zoo polished los yog tiv thaiv, nws tuaj yeem ua qhov ntxeem tau ntau dua thiab muaj kev cuam tshuam rau corrosion lossis lwm yam degradation.
Dab tsi yog cov khoom siv hlau nrov nrov hauv khw?
Yog, muaj ntau yam khoom siv hlau ntxeem tau nrov ntawm kev ua lag luam. Qee yam ntawm cov khoom siv hlau porous feem ntau yog:
5.1 Perforated Hlau Phaj
Cov no yog cov hlau tiaj tus nrog tswj porosity uas tuaj yeem siv rau kev pom, diffusion thiab lwm yam kev siv.
Lawv feem ntau yog ua los ntawm stainless hlau, titanium los yog npib tsib xee alloys.
5.2 Porous Hlau Tube
Cov no yog cov raj hollow nrog tswj porosity uas tuaj yeem siv rau kev pom, aeration, thiab lwm yam kev siv.
Lawv feem ntau yog ua los ntawm stainless hlau lossis titanium.
5.3 Porous Aluminium Phaj
Cov no yog cov ntawv tiaj tus ntawm txhuas nrog kev tswj cov porosity uas tuaj yeem siv rau kev pom, diffusion thiab lwm yam kev siv.
Lawv feem ntau siv hauv kev lag luam xws li aerospace thiab automotive.
5.4. Perforated Aluminium Phaj
Cov no yog cov ntawv tiaj tus ntawm txhuas nrog kev tswj cov porosity uas tuaj yeem siv rau kev pom, diffusion thiab lwm yam kev siv.
Lawv feem ntau siv hauv kev lag luam xws li hluav taws xob thiab khoom siv kho mob.
5.5 Porous Hlau Ua Npuas Ncauj
Cov no yog lub teeb yuag peb-dimensional qauv ua los ntawm cov hlau nrog tswj porosity.
Lawv feem ntau siv nyob rau hauv kev lag luam xws li lub zog, aerospace thiab automotive rau kev siv xws li cov cua kub exchangers,
catalytic converters thiab suab rwb thaiv tsev.
nyob rau hauv xaus
Hauv cov ntsiab lus, cov hlau tuaj yeem ntxeem tau vim muaj ntau yam laj thawj xws li cov txheej txheem hlau tsim, raug corrosive.
ib puag ncig, los yog npaj siv. Porous hlau muaj ntau daim ntawv thov hauv kev lag luam sib txawv thiab lawv cov khoom tuaj yeem ua tau
txhim kho kom tau raws li cov kev xav tau tshwj xeeb. Porosity nyob rau hauv cov hlau yuav tsum tau kuaj xyuas kom lawv zoo thiab kev ntseeg tau. Nrog tsim nyog
kev ntsuas, porosity hauv cov hlau tuaj yeem txo qis, ua rau cov khoom siv hlau muaj zog thiab ruaj khov dua.
Post lub sij hawm: May-09-2023
