Kev Siv Tshuab Tsim Khoom Hlau Uas Tiv Thaiv Kub Siab
Qhov xav tau cov ntaub ntawv uas tuaj yeem tiv taus qhov kub thiab txias heev txuas ntxiv mus nrog kev txhim kho ntawm kev lag luam niaj hnub no. Cov roj turbines hauv cov chaw tsim hluav taws xob, lub cav dav hlau, rockets, cov khoom siv petrochemical, thiab txawm tias reactors thiab cov txheej txheem ua kom sov xav tau cov hlau uas tsis yog tsuas yog muaj zog tab sis kuj ruaj khov thaum raug rau qhov kub thiab txias rau lub sijhawm ntev. Qhov no yog qhov uas cov hlau kub siab ua lub luag haujlwm tseem ceeb. Tsab xov xwm no tham txog cov ntsiab lus yooj yim, cov hom khoom siv, thiab cov thev naus laus zis tseem ceeb hauv kev tsim khoom thiab kev ua cov hlau kub siab, suav nrog cov teeb meem thiab cov lus qhia tshiab.
Hlau Uas Tiv Thaiv Tau Kub Siab Yog Dab Tsi?
Cov hlau uas tiv taus kub siab yog cov hlau lossis cov hlau sib xyaw uas tsim los tswj lawv cov khoom siv kho tshuab thiab tshuaj lom neeg ntawm qhov kub siab—feem ntau siab dua 500°C, thiab txawm tias siab dua 1000°C rau qee yam kev siv. Hauv qab cov xwm txheej no, ntau cov hlau feem ntau yuav muaj kev mos, kev hloov pauv mus tas li (nkag mus), kev ua kom puas tsuaj loj heev, lossis kev xeb kub. Cov hlau uas tiv taus kub siab yuav tsum muaj cov khoom sib xyaw ua ke hauv qab no:
1. Muaj zog heev thaum kub heev (kub heev)
2. Kev tiv thaiv creep (kev tiv thaiv kev hloov pauv qeeb vim yog qhov thauj khoom tas li)
3. Kev tiv thaiv oxidation thiab cua sov corrosion
4. Kev ruaj khov ntawm cov qauv me me
5. Kev tiv thaiv kev qaug zog thermal vim yog cua sov-txias voj voog
Cov Hom Hlau Uas Tiv Thaiv Kub Siab
Qee cov tsev neeg siv khoom siv feem ntau yog:
1. Cov hlau nplaum uas ua los ntawm nickel (Ni-based superalloys)
Nws yog cov khoom siv tseem ceeb rau cov hniav roj turbine thiab cov cav dav hlau vim nws tuaj yeem tiv taus qhov kub siab heev thaum tseem tswj tau lub zog. Nickel yog alloyed nrog cov ntsiab lus xws li chromium (Cr), cobalt (Co), txhuas (Al), titanium (Ti), molybdenum (Mo), tungsten (W), thiab rhenium (Re). Qhov kev sib xyaw ua ke no ua rau muaj zog los ntawm kev nag ntawm γ' (gamma prime) theem, uas yog qhov zoo heev ntawm kev tiv taus creep.
2. Cobalt-based superalloy (Co-based)
Nws muaj kev tiv taus xeb zoo heev thiab siv rau hauv qee yam khoom kub-yaj. Txawm li cas los xij, nws lub zog nkag feem ntau qis dua li cov hlau nickel rau cov ntawv thov kub siab.
3. Cov hlau uas tiv taus cua sov thiab cov hlau tsis xeb
Feem ntau siv rau qhov kub nruab nrab mus rau siab (piv txwv li, 500–800°C). Kev ntxiv Cr ua rau kev tiv taus oxidation zoo dua, thaum Mo, V, thiab Nb pab tiv taus kev nkag.
4. Cov hlau titanium (Ti alloys)
Titanium muaj qhov sib piv ntawm lub zog thiab qhov hnyav zoo dua, tab sis nws cov kev txwv kub ua haujlwm feem ntau qis dua li cov nickel superalloys. Nws yog qhov tsim nyog rau lub cav nruab nrab kub thiab cov khoom siv dav hlau.
5. Cov hlau refractory (W, Mo, Ta, Nb)
Nws muaj qhov melting siab heev thiab siv rau cov ntawv thov hnyav, tab sis feem ntau ntsib teeb meem nrog oxidation thiab cov nqi ua tiav.
Cov Theem thiab Tshuab rau Kev Ua Cov Hlau Uas Tiv Thaiv Kub Siab
1. Kev tsim cov khoom sib xyaw thiab kev tsim kho me me
Cov thev naus laus zis niaj hnub pib nrog kev tsim cov hlau sib xyaw siv txoj hauv kev siv hlau. Cov khoom sib xyaw raug xaiv los txhawb kev ua kom muaj zog (piv txwv li, nag lossis daus, kev ua kom cov kua khov kho) thiab tsim cov txheej txheem oxide tiv thaiv ruaj khov. Qhov tseem ceeb sib npaug yog kev tswj hwm microstructural: qhov loj me ntawm cov noob, kev faib tawm ntawm cov nag lossis daus, thiab cov theem ua kom muaj zog.
Niaj hnub no, kev tsim cov hlau alloy kuj tau txais kev pab los ntawm kev sim ua lej xws li CALPHAD thiab thermodynamic modeling los kwv yees cov theem uas tsim ntawm ntau qhov kub thiab txias.
2. Kev yaj siab heev: Kev yaj los ntawm lub tshuab nqus tsev thiab VAR
Ib qho ntawm cov teeb meem tseem ceeb hauv kev tsim cov hlau refractory yog kev tswj hwm qhov huv thiab tswj cov khoom reactive. Yog li ntawd, cov txheej txheem yaj feem ntau yog ua nyob rau hauv lub tshuab nqus tsev lossis inert atmospheres.
– Kev Siv Lub Tshuab Nqus Tsev (Vim): hlau raug yaj siv lub tshuab nqus tsev, txo cov pa oxygen, nitrogen, thiab hydrogen uas ua rau muaj porosity thiab brittleness.
– Kev Siv Lub Tshuab Nqus Tsev Arc Remelting (VAR): thawj cov ingot yaj raug rov yaj nrog lub tshuab hluav taws xob hauv lub tshuab nqus tsev kom txhim kho kev sib xws thiab txo cov khoom sib cais.
- Electroslag Remelting (ESR) kuj tseem siv los txhim kho qhov huv ntawm cov hlau los ntawm kev siv slag los ua kom huv.
Cov txheej txheem sib xyaw ua ke no tsim cov ingots zoo uas tsim nyog rau cov khoom tseem ceeb xws li turbines thiab propulsion systems.
3. Kev ua kom zoo thiab kev ua kom khov kho
Rau cov khoom sib xyaw ua ke xws li cov hniav turbine, kev siv tshuab casting (precision casting siv cov pwm ceramic) yog cov thev naus laus zis tseem ceeb. Txawm li cas los xij, qhov kev hloov pauv tseem ceeb hauv ntiaj teb ntawm superalloys yog cov txheej txheem ntawm kev ua kom khov kho:
- Kev Taw Qhia Kom Ruaj Khoov (DS): cov qauv noob qoob loo yog ua kom nthuav dav mus rau hauv ib qho kev taw qhia, txo cov ciam teb ntawm cov noob qoob loo uas yooj yim nkag mus.
– Kev Siv Crystal (SX) Casting: Cov hniav turbine yog ua los ntawm cov hlau tsis muaj ciam teb. Qhov no ua rau muaj kev tiv thaiv kev nkag thiab kev qaug zog ntawm cua sov, ua rau kev ua haujlwm ntawm qhov kub siab dua.
SX thev naus laus zis yog ib qho ntawm cov kev ua tiav tseem ceeb tshaj plaws hauv kev ua hlau niaj hnub no, tab sis nws xav tau kev tswj hwm cov txheej txheem nruj heev thiab kim heev.
4. Hmoov metallurgy (Hmoov metallurgy)
Rau qee cov hlau sib xyaw, tshwj xeeb tshaj yog cov uas nyuaj rau forging lossis yooj yim sib cais thaum lub sijhawm casting, hmoov metallurgy muaj lwm txoj hauv kev zoo dua. Cov txheej txheem suav nrog kev tsim cov hmoov (piv txwv li, los ntawm kev siv roj atomization), uas tom qab ntawd compacted thiab sintered.
Cov thev naus laus zis tseem ceeb ntawm no yog:
– Kev Nias Kub Isostatic (HIP): Cov hmoov raug nias kom nruj siv kev siab thiab kub sib npaug los ntawm txhua qhov kev taw qhia. HIP kuj tseem siv los tshem tawm cov qhov hws hauv cov khoom cam khwb cia.
- Isothermal forging: forging ntawm qhov kub tswj tau los tsim cov qauv me me thiab sib xws.
Hmoov metallurgy yog siv dav hauv turbine disks vim nws xav tau kev sib xyaw ua ke ntawm lub zog siab thiab kev qaug zog.
5. Kev tsim thiab ua ntxiv
Tom qab cov ingot raug tsim, ntau yam khoom xav tau cov txheej txheem yas deformation xws li forging, dov, lossis extrusion. Rau cov hlau refractory, cov txheej txheem no nyuaj dua vim tias cov khoom siv feem ntau muaj lub qhov rais ua haujlwm me me. Kev tswj qhov kub thiab txias, tus nqi deformation, thiab txias cuam tshuam rau qhov loj me ntawm cov noob thiab cov av noo.
6. Kev kho cua sov (kev kho cua sov)
Kev kho cua sov yog "qhov tseem ceeb" rau kev ua kom muaj zog hauv ntau cov hlau sib xyaw. Cov kauj ruam feem ntau suav nrog:
- Kev kho cov tshuaj: yaj qee cov theem kom qhov kev faib tawm ntawm cov ntsiab lus yog homogeneous.
– Kev laus: tsim cov precipitates me me uas ua rau cov khoom muaj zog (piv txwv li γ' hauv nickel superalloys).
- Kev txo kev ntxhov siab: txo cov kev ntxhov siab seem uas tshwm sim los ntawm cov txheej txheem tsim khoom.
Kev kho cua sov kom zoo dua qub tuaj yeem hloov pauv cov khoom siv tau zoo heev, piv txwv li ua rau muaj kev tiv thaiv kab nkag mus yam tsis tas yuav txo qhov tawv.
7. Kev tiv thaiv txheej: Thermal Barrier Txheej
Feem ntau, nws tsis yog tsuas yog cov hlau sib xyaw xwb uas tseem ceeb, tab sis kuj yog cov txheej tiv thaiv. Cov turbines niaj hnub no siv cov txheej tiv thaiv ceramic Thermal Barrier Coatings (TBCs) (piv txwv li, yttria-stabilized zirconia / YSZ) los txo cov cua sov nkag mus rau hauv cov hlau.
Ib lub "txheej txheej sib txuas" ntawm cov hlau, xws li MCrAlY (M = Ni/Co), pab tsim ib qho alumina tiv thaiv uas tiv taus oxidation. TBC tso cai rau qhov kub ntawm cov roj ua haujlwm siab dua, txhim kho kev ua haujlwm ntawm lub cav.
8. Kev Tsim Khoom Ntxiv
Nyob rau xyoo tas los no, cov txheej txheem luam ntawv hlau 3D xws li Laser Powder Bed Fusion (LPBF) thiab Directed Energy Deposition (DED) tau pib siv rau cov superalloys. Lawv qhov zoo suav nrog kev tsim qauv nyuaj, kev txo cov khib nyiab, thiab kev koom ua ke ntawm cov khoom. Txawm li cas los xij, lawv ntsib teeb meem loj: kev tawg kub, porosity, kev ntxhov siab seem, thiab qhov xav tau cov txheej txheem raug heev. Kev ua tiav tom qab xws li HIP thiab kev kho cua sov yuav luag txhua lub sijhawm.
Cov Kev Cov Teeb Meem Tseem Ceeb thiab Cov Lus Qhia Txog Kev Tsim Kho Tshiab
Kev tsim cov hlau refractory yeej ib txwm yog qhov kev sib haum xeeb ntawm kev ua tau zoo, tus nqi, thiab yooj yim ntawm kev tsim khoom. Cov teeb meem tseem ceeb suav nrog kev tswj cov qhov tsis zoo me me (qhov hws, tawg), kev tiv thaiv corrosion hauv cov chaw ua phem, thiab kev vam khom rau cov ntsiab lus kim xws li rhenium. Yog li ntawd, kev tshawb fawb tam sim no tsom mus rau:
– Kev tsim cov superalloys nrog cov ntsiab lus qis dua ntawm cov khoom kim heev
- Cov hlau sib xyaw tshiab xws li cov hlau sib xyaw siab-entropy rau qhov kub siab
- Kev txhim kho ntawm cov txheej TBC ntev dua
- Cov txheej txheem tsim khoom ntxiv uas ruaj khov dua thiab tau ntawv pov thawj rau cov ntawv thov tseem ceeb
Kev kaw
Kev siv tshuab ua hlau kub siab yog kev sib xyaw ua ke ntawm cov ntaub ntawv tshawb fawb, metallurgy, thiab kev tswj hwm cov txheej txheem tsim khoom siab heev. Txij li kev yaj lub tshuab nqus tsev thiab kev casting precision ib leeg-crystal, hmoov metallurgy, kev kho cua sov, thiab txheej thermal barrier, txhua kauj ruam txiav txim siab qhov ua tau zoo kawg ntawm cov khoom siv. Nrog rau qhov kev thov nce ntxiv rau kev siv hluav taws xob zoo thiab cov cav ua haujlwm siab, kev tsim kho tshiab hauv thaj chaw no yuav txuas ntxiv ua lub hauv paus tseem ceeb rau kev nce qib hauv kev tsav dav hlau, kev tsim hluav taws xob, thiab cov thev naus laus zis yav tom ntej.
