Daim ntawv tshaj tawm no muab cov ntaub ntawv nruj, pov thawj -raws li kev sib piv ntawmInconel 625 (UNS N06625) Cov.tawm tsam ob lwm yam nickel siv dav heev-raws li superalloys - Inconel 718 thiab Hastelloy X - rau daim ntawv thov nyob rau hauv aerospace gas turbine engine Cheebtsam raug kub heev. Inconel 625 yog ib qho khoom siv - kev daws teeb meem - muaj zog npib tsib xee- chromium alloy renowned rau nws qhov tshwj xeeb ua ke ntawm siab - kub lub zog, oxidation tsis kam, thiab qaug zog kev ua tau zoo nyob rau hauv ib puag ncig tshaj 1000℃(1832℃F).
Hauv cov ntsiab lus yooj yim: Inconel 625 yog cov hlau uas xaiv thaum lub dav hlau tiv thaiv yuav tsum muaj sia nyob nrog cov cua sov, corrosive combustion gases, thiab rov ua dua thermal cycling - tej yam kev mob nyob rau hauv uas feem ntau lwm yam engineering alloys, nrog rau cov nyiam heev.ib 718, tsuas ua tsis tau.
Nrhiav qhov tseem ceeb:Rau cov khoom kub- ntu ntu xws li combustor liners, tso pa tawm, thiab tom qab cov khoom sib dhos ua haujlwm siab tshaj 650 degree, Inconel 625 muaj kev txiav txim siab ua tau zoo dua Inconel 718, uas yog txwv rau cov ntawv thov hauv qab kwv yees li 650℃vim poob ntawm kev ntxiv dag zog rau precipitates ntawm qhov kub siab dua.
Taw qhia
Niaj hnub nimno dav hlau tshuab ua haujlwm ntawm qhov kev txwv ntawm cov ntaub ntawv tshawb fawb. Nyob rau hauv lub turbofan lub combustor, cov roj kub tuaj yeem tshaj 2000℃- deb tshaj qhov melting point ntawm tej hlau alloy. Cheebtsam muaj kev tiv thaiv los ntawm cua txias zaj duab xis, thermal barrier coatings, thiab ua tib zoo tsim, tab sis cov ntaub ntawv hauv qab yuav tsum tseem tiv taus cov hlau kub ntawm 800-1100℃thaum tiv oxidation, kub corrosion, creep, thiab thermal qaug zog.
Xaiv txoj cai alloy rau txhua cheeb tsam lub cav tsis yog qhov nyiam; nws yog ib qho teeb meem ntawm kev nyab xeeb ntawm kev ya davhlau, kev ua raws li daim ntawv pov thawj, thiab kev khwv nyiaj txiag. Ib qho kev tivthaiv uas ua tsis tiav ntxov vim yog oxidation lossis creep tuaj yeem ua rau muaj kev puas tsuaj rau lub cav tsis ua haujlwm, kev saib xyuas tsis tau them nqi, thiab kev tswj hwm hauv av ntawm tag nrho cov nkoj.Ntawm lub nickel superalloy tsev neeg, peb qib yeej kub -section thiab structural engine tsim:
• Inconel 625 (UNS N06625): Ib qho khoom siv - kev daws teeb meem - muaj zog hlau alloy sib txuas ua ke oxidation tsis kam, qaug zog, thiab corrosion kuj ntawm qhov kub thiab txias mus txog 1000℃.
• Inconel 718 (UNS N07718): Cov nag lossis daus -hardened (hnub nyoog-hardenable) alloy muab lub zog siab heev- rau- qhov hnyav piv, tab sis txwv rau qhov ntsuas kub hauv qab li ntawm 650℃.
• Hastelloy X(UNS N06002): Ib qho nickel-chromium- hlau- molybdenum alloy nrog cov oxidation zoo heev rau 1150 degree, feem ntau siv hauv cov khoom siv hluav taws xob thiab cov hluav taws xob tom qab.
Tsab ntawv xov xwm no suav txog qhov sib txawv ntawm qhov kev ua tau zoo thoob plaws xya qhov tseem ceeb kom cov kws tsim khoom siv hluav taws xob, cov kws tshaj lij cov ntaub ntawv, thiab cov neeg ua haujlwm yuav khoom tuaj yeem tiv thaiv tau, cov ntaub ntawv - tsav cov kev txiav txim siab xaiv alloy.
Nkag siab txog Alloy
Ib 625
Inconel 625 muab nws qhov tshwj xeeb siab - qhov kub thiab txias ua haujlwm los ntawm kev sib xyaw tshwj xeeb ntawm chromium (20-23%) rau oxidation thiab corrosion kuj, thiab molybdenum ntxiv rau niobium rau khoom- kev daws teeb meem. Tsis zoo li nag lossis daus- cov alloys hardened, 625 tsis cia siab rau cov cua sov-kho cov theem intermetallic rau nws lub zog.
Qhov no txhais tau hais tias nws cov khoom siv kho tshuab nyob ruaj khov nyob rau hauv ntau qhov kub thiab txias thiab tsis degrade dhau los ntawm ntau tshaj - laus thaum lub sij hawm ntev siab - qhov kub thiab txias.Cov chromium cov ntsiab lus tsim ib tug ntom, adherent chromium oxide (Cr₂O₃) txheej tiv thaiv ntawm lub alloy nto thaum raug siab - cua kub los yog gases.
Cov nplai oxide no yog tus kheej - kho - yog tias puas, nws hloov kho sai, muab kev tiv thaiv txuas ntxiv tiv thaiv oxidation ntxiv. Qhov ntxiv molybdenum ntxiv txhim khu kev tiv thaiv hauv cheeb tsam corrosion thiab pitting nyob rau hauv txhoj puab heev, leej faj-muaj ib puag ncig combustion.
ib 718
Inconel 718 ua tiav nws lub zog siab heev los ntawm nag lossis daus hardening: tswj kev kho cua sov ua rau tsim cov gamma-prime ( ′) thiab gamma-ob npaug-prime ( ″) intermetallic theem nyob rau hauv nickel- hlau matrix. Cov theem no impede dislocation txav, muab 718 tensile lub zog muaj nuj nqis nyob deb tshaj cov khoom ntawm cov khoom- tov alloys ntawm chav tsev thiab nruab nrab kub.
Txawm li cas los xij, saum toj no kwv yees li 650 degree, cov precipitates muaj zog no pib coarsen thiab yaj, ua rau lub zog poob sai. Qhov no yog vim li cas Inconel 718, txawm tias yog cov nickel superalloy siv ntau tshaj plaws los ntawm tonnage nyob rau hauv aerospace (siv ntau nyob rau hauv turbine disks, shafts, thiab casings), yog unsuitable rau kub -section Cheebtsam raug rau combustion gas kub.
Hastelloy X
Hastelloy X yog npib tsib xee-chromium- hlau- molybdenum alloy tshwj xeeb tsim rau oxidation zoo heev txog 1150 degree, ua ke nrog zoo fabricability rau daim ntawv- hlau combustor Cheebtsam. Nws yog cov khoom muaj zog- kev daws teeb meem, zoo ib yam li hauv lub tswv yim rau Inconel 625, tab sis nrog qhov sib npaug sib txawv ntawm cov ntsiab lus optimized rau daim ntawv sib sau thiab vuam hauv combustor liner manufacturing.
Qhov kev xaiv ntawm cov khoom siv -solution alloys (625, Hastelloy X) thiab nag lossis daus-hardened alloys (718) yog qhov kev xaiv ntawm kev ruaj ntseg siab - qhov kub thiab txias thiab qhov siab tshaj plaws hauv chav tsev / nruab nrab - qhov kub thiab txias. Tsis muaj ib qho 'zoo tshaj' alloy - tsuas yog qhov zoo tshaj plaws alloy rau ib cheeb tsam kub thiab chaw thau khoom.
Kev sib piv tshuaj lom neeg
Table 1 nthuav qhia cov ntawv pov thawj tshuaj muaj pes tsawg leeg rau Inconel 625, Inconel 718, thiab Hastelloy X raws li tau teev tseg hauv ASTM B443 (phaj / ntawv) thiab ASTM B446 (bar / forging), thawj cov qauv khoom siv los ntawm aerospace khoom specifications xws li AMS 5599 thiab AMS. Tag nrho cov nqi yog 566%.
| Element | Inconel 625 (wt%) | Inconel 718 (wt%) | Hastelloy X (wt%) | ASTM Txuj | Muaj nuj nqi |
| Nickel (Ni) | 5 8,0mn. | 50.0–55.0 | 4 7,0mn. | B443 / B446 | Matrix |
| Chromium (Cr) | 20.0–23.0 | 17.0–21.0 | 20.5–23.0 | B443 / B446 | Oxidation tiv taus. |
| Molybdenum (hli) | 8.0–10.0 | 2.8–3.3 | 8.0–10.0 | B443 / B446 | Khoom- daws lub zog |
| Niobium (Nb + Ta) | 3.15–4.15 | 4.75–5.5 | - | B443 / B446 | Khoom- daws lub zog |
| Hlau (Fe) | Tsawg dua lossis sib npaug li 5.0 | Tshuav | 17.0–20.0 | B443 / B446 | Base / muab tub lim |
| Cobalt (zeeg) | Tsawg dua los yog sib npaug rau 1.0 | Tsawg dua los yog sib npaug rau 1.0 | 0.5–2.5 | B443 / B446 | Kev tuav ruaj khov |
| Cov pa roj carbon (C) | Tsawg dua lossis sib npaug li 0.10 | Tsawg dua los yog sib npaug li 0.08 | 0.05–0.15 | B443 / B446 | Carbide tsim |
| Aluminium + Titanium | Tsawg dua los yog sib npaug rau 0.40 + 0.40 | 0.2–0.8 / 0.65–1.15 | Tsawg dua los yog sib npaug li 0.50 | B443 / B446 | Gamma{0}}prime (718 nkaus xwb) |
Table 1: Tshuaj Chemical Composition ntawm Inconel 625, Inconel 718, thiab Hastelloy X|Tau qhov twg los: ASTM B443 / B443M-23 thiab ASTM B446 / B446M-23, ASTM International; AMS 5599 thiab AMS 5666, SAE International
Qhov sib txawv tseem ceeb tshaj plaws yog qhov tsis muaj txiaj ntsig ntawm txhuas thiab titanium hauv Inconel 625, piv rau Inconel 718. Cov ntsiab lus no yog qhov tseem ceeb rau kev tsim cov gamma -prime precipitates uas ntxiv dag zog rau 718 - tab sis lawv kuj yog vim li cas 718 poob lub zog ntawm qhov kub siab, vim cov precipitates no tsis ruaj khov saum toj no 6. Inconel 625 es tsis txhob cia siab rau molybdenum thiab niobium yaj ncaj qha rau hauv cov nickel-chromium matrix, ib qho kev txhawb zog uas tseem muaj txiaj ntsig zoo ntawm qhov kub thiab txias ntau dua.
Siab -Tsub Mechanical Properties (ntawm 1000 degree)
Cov lus nug uas txhais tau rau txhua lub dav hlau kub - cov khoom seem yog: nws coj li cas ntawm qhov kub thiab txias nws yuav ua tau zoo hauv kev pabcuam? Table 2 piv cov cuab yeej tseem ceeb ntawm tag nrho peb cov alloys ntsuas ntawm 1000℃(1832℃F), qhov kub thiab txias tau hais nyob rau hauv tsab xov xwm no lub npe thiab tus neeg sawv cev ntawm combustor liner thiab cov pa duct nyob rau hauv niaj hnub turbofan xyaw.
| Khoom (ntawm 1000℃/ 1832℃F) | Ib 625 | ib 718 | Hastelloy X | Test Standard |
| Tensile zog (MPa) | ~285 | Tsis pom zoo | ~190 | ASTM E21 |
| Yield zog (MPa) | ~240 | Tsis pom zoo | ~150 | ASTM E21 |
| Elongation (%) | ~60 | Tsis pom zoo | ~45 | ASTM E21 |
| Max. Kev Pabcuam Nruam Temp (degree) | ~980–1095 | ~650 | ~1150 | OEM tsim cov ntaub ntawv |
| Creep-Rupture Life @ 980℃/ 21 MPa (h) | ~100–150 | N/A (ntau tshaj qhov txwv) | ~50–80 | ASTM E139 Cov khoom siv |
| Oxidation tus nqi @ 1000℃(mg / cm² / 1000h) | < 5 | N/A (ntau tshaj qhov txwv) | < 3 | ASTM B76 |
| Qhov ceev (g / cm³) | 8.44 | 8.19 | 8.22 | ASTM B 311 Cov Lus Qhia Tshwj Xeeb |
Table 2: Mechanical Properties ntawm 1000 degree|Tau qhov twg los: ASTM E21 (siab kub tensile kuaj); ASTM E139 (nruab- kev kuaj kev puas tsuaj); ASTM B76 (Kev kuaj oxidation kuj); OEM luam tawm cov ntaub ntawv tsim qauv thiab cov ntawv xov xwm tshwj xeeb hlau
Qhov tseem ceeb ntawm kev tshem tawm los ntawm Table 2 yog tias Inconel 718 tsis raug ntsuas rau kev pabcuam txuas ntxiv ntawm 1000℃ntawm tag nrho - nws qhov ntsuas kub ntawm lub qab nthab ntawm kwv yees li 650℃yog nyob qis dua qhov pib no, thiab sim siv nws ntawm no yuav ua rau lub zog poob sai, nkag deformation, thiab qhov kawg tsis ua haujlwm.
Inconel 625, los ntawm qhov sib txawv, khaws cov tensile thiab yield zog txawm nyob rau ntawm 1000 degree, thaum tuav qis oxidation tus nqi thiab zoo elongation (ductility), ua rau nws haum rau cov khoom uas yuav tsum flex thiab deform me ntsis thaum lub sij hawm thermal cycling tsis tawg.
Hastelloy X qhia tau hais tias qhov siab tshaj qhov kub ntawm lub qab nthab me ntsis (~ 1150 degree) vim nws cov oxidation zoo heev, tab sis nws tensile thiab creep-rupture zog ntawm 1000℃feem ntau qis dua Inconel 625, ua 625 qhov kev xaiv uas ob qho tib si lub zog thiab oxidation kuj tseem ceeb heev.
Oxidation, Kub Corrosion, thiab Fatigue Performance
Tshaj li lub zog tensile yooj yim, aerospace kub- ntu cov khoom sib xyaw ua ke ntawm cov txheej txheem degradation ua haujlwm ib txhij: oxidation los ntawm huab cua kub, kub corrosion los ntawm sulfur thiab sodium compounds nyob rau hauv combustion gases (tshwj xeeb tshaj yog rau cov cav kub kub qis dua{1}} qib roj los yog kev khiav hauj lwm nyob ze marine ib puag ncig), thermal qaug zog thiab rov ua dua cov tshuab cua sov. loading ntawm qhov kub thiab txias. Table 3 piv cov kev ua tau zoo thoob plaws rau 6 lub tshuab degradation.
| Degradation Mechanism | Ib 625 | ib 718 | Test/Reference | Kev soj ntsuam tseem ceeb |
| Oxidation Resistance (1000 degree, huab cua) | Zoo heev - tiv thaiv Cr₂O₃ nplai | Tsis zoo siab tshaj 650 degree | ASTM B76 / NACE TM0103 | 625 daim ntawv ruaj khov oxide txheej ntawm temp |
| Kub Corrosion (sulfidation) | Zoo tsis kam | Marginal | ASTM G79, ASTM G79 | 625 Mo / Cr piv tiv thaiv S nres |
| Thermal Fatigue Resistance | Siab - qis thermal expansion | Nruab nrab | ASTM E 606 1 | 625 nyiam rau cyclic thermal loads |
| Fatigue Crack Loj hlob (siab temp) | Kev nthuav tawm qeeb | Ceev tshaj qhov ntsuas kub | ASTM E647 Cov khoom lag luam | 625 tiv thaiv kev loj hlob ntawm 1000 degree |
| Stress Repture (ntev ntev, 980 degree) | Retains ~ 70% lub zog ntawm 1000h | Tsis ntsuas | ASTM E139 Cov khoom siv | 625 haum rau kev ua haujlwm siab -temp lub luag haujlwm |
| Embrittlement tom qab ntev raug | Tsawg kawg mus txog 1000 degree | Significant >650 degree | TIAB SA 5666 | 625 ruaj khov microstructure |
Table 3: Oxidation, Kub Corrosion, thiab Fatigue Performance|Qhov chaw: ASTM B76 (oxidation kuj); NACE TM0103 (siab-kub corrosion); ASTM G79 (kev kuaj kub corrosion); ASTM E606 (Kev ntsuas kub ua kom qaug zog); ASTM E647 (kev qaug zog tawg tawg); TIAB SA 5666
Vim li cas Oxidation Resistance yog Qhov Kev Txiav Txim Siab
Oxidation yog arguably ib qho tseem ceeb tshaj plaws degradation mechanism rau kub -section aerospace Cheebtsam. Tsis zoo li qaug zog lossis nkag mus, uas qee zaum tuaj yeem tswj hwm los ntawm cov qauv tsim thiab kev soj ntsuam lub sijhawm, oxidation yog cov tshuaj tiv thaiv txuas ntxiv uas ua rau cov khoom siv ntawm cov khoom siv tau zoo zuj zus.
Thaum cov txheej txheem tiv thaiv oxide raug cuam tshuam - los ntawm thermal cycling -induced spallation, erosion los ntawm particulates, los yog tshuaj tua kab mob - lub hauv paus hlau oxidizes sai, ua rau phab ntsa thinning thiab nws thiaj li tsis ua hauj lwm.
Inconel 625's chromium- nplua nuj oxide nplai yog qhov tshwj xeeb ruaj khov thiab ua raws li kev caij tsheb kauj vab thermal, uas yog vim li cas cov hlau alloy yog qhov kev xaiv zoo tshaj plaws rau cov khoom siv nquag pib lub cav pib- nres cycles, xws li combustor liners thiab tso pa tawm hauv kev lag luam thiab tub rog dav hlau.
Thermal Fatigue thiab Low -Cycle Fatigue Resistance
Aerospace cav Cheebtsam muaj ntau txhiab lub voj voog thermal dhau ntawm lawv lub neej kev pabcuam - txhua lub cav pib, hloov pauv, thiab kaw ua rau lub voj voog thermal. Inconel 625 tus thermal expansion coefficient tsis tshua muaj siab ua ke nrog nws cov ductility siab tso cai rau nws kom haum raws li cov kev ntxhov siab no yam tsis tau tsim cov kab nrib pleb uas pib qaug zog. Cov cuab yeej no yog qhov laj thawj tseem ceeb vim li cas 625 tau teev tseg rau kev hloov pauv tau yooj yim, cov pob qij txha nthuav dav, thiab lwm yam khoom uas yuav tsum tau rov ua dua thaum ua haujlwm.
Aerospace Certification thiab Standards Compliance
Kev xaiv cov khoom siv hauv aerospace yog tswj hwm los ntawm cov txheej txheem nruj ntawm cov lus qhia tshwj xeeb, cov txheej txheem zoo, thiab cov ntawv pov thawj yuav tsum tau ua. Tsis muaj alloy - tsis hais txog nws cov txiaj ntsig kev ua haujlwm - tuaj yeem siv rau hauv lub tshuab hluav taws xob uas muaj ntawv pov thawj yam tsis muaj kev ua raws li AMS (Aerospace Material Specification), ASTM lub hauv paus specifications, thiab kev tswj xyuas zoo. Table 4 piav qhia txog cov qauv tseem ceeb siv tau rau Inconel 625 thiab Inconel 718 hauv kev siv tshuab aerospace.
| Txheem / Lub Cev | 625 npe? | 718 npe? | Scope / Qhov cuam tshuam |
| AMS 5666 (Bar / Forging) | Yog lawm | AMS 5662 (Sib cais) | Aerospace khoom spec rau Ni-base superalloy bar |
| AMS 5599 (Tshooj / Phaj) | Yog lawm | TIAB SA 5596 | Daim ntawv thiab sawb rau combustor liners, ducting |
| ASTM B443 / B446 | Yog lawm | B637 | Phaj / ntawv thiab bar tshuaj muaj pes tsawg leeg |
| AS9100 (Qee yam Mgmt) | Yog lawm | Yog lawm | Aerospace zoo tswj system yuav tsum tau |
| NADCAP (Cov Txheej Txheem Tshwj Xeeb) | Yog lawm | Yog lawm | Kev kho cua sov, vuam, NDT daim ntawv pov thawj |
| FAA/EASA Part 33 | Yog (engine cert) | Yog (engine cert) | Cav airworthiness ntawv pov thawj hauv paus |
| AWS D17.1 | Yog lawm | Yog lawm | Aerospace fusion vuam specification |
Table 4: Aerospace Standards thiab Certifications|Qhov chaw: SAE International AMS 5666 (2023), AMS 5599 (2023), AMS 5662, AMS 5596; ASTM B443 / B443M -23, ASTM B637; AS9100D Kev Tswj Xyuas Zoo; NADCAP (PRI); FAA 14 CFR Part 33; EASA CS-E; AWS D17.1/D17.1M
Daim ntawv qhia txog kev yuav khoom: AMS specifications txhais tsis tau tsuas yog tshuaj lom neeg muaj pes tsawg leeg thiab txhua yam khoom tab sis kuj melting xyaum (nqus induction melting plus nqus arc remelting, los yog VIM-VAR, feem ntau yuav tsum tau rau qhov tseem ceeb rotating qhov chaw), grain loj qhov yuav tsum tau, thiab tsis yog -kev soj ntsuam kev puas tsuaj (NDT) kev txais.
Cov ntaub ntawv pov thawj (Certificate of Conformance) yuav tsum taug qab txhua yam khoom rov qab mus rau qhov qub yaj thaum tshav kub kub, thiab NADCAP-cov neeg muag khoom raug lees paub feem ntau yuav tsum tau ua rau cov txheej txheem tshwj xeeb xws li kev kho cua sov thiab vuam.
Cov lus nug nquag
Q1: Inconel 625 puas tuaj yeem siv tsis tu ncua saum 1000 degree?
Inconel 625 tuaj yeem zam tau luv luv - lub sijhawm mus ncig ua si siab dua 1000℃thiab feem ntau raug ntsuas rau kev pabcuam txuas mus txog li 980-1095℃nyob ntawm qhov tshwj xeeb thauj khoom thiab lub neej ua haujlwm xav tau. Saum toj no ntau yam, oxidation tus nqi nce thiab creep-rupture lub neej txo qis heev. Rau cov ntawv thov uas xav tau kev pabcuam tas mus li siab dua 1100 degree, alloys xws li Hastelloy X lossis cobalt-raws li superalloys nrog thermal barrier coatings feem ntau tau teev tseg.
Q2: Vim li cas tsis Inconel 718 tsuas yog siv ntau chromium los txhim kho oxidation tsis kam?
Kev nce chromium cov ntsiab lus hauv Inconel 718 yuav tsis daws nws qhov tseem ceeb siab - qhov kub thiab txias, uas yog qhov thermal instability ntawm nws gamma -prime thiab gamma-ob npaug -prime reinforcing precipitates. Txawm tias muaj kev txhim kho oxidation tsis kam, cov hlau tseem yuav poob nws lub zog siab tshaj 650℃raws li cov nag lossis daus coarsen thiab yaj. Qhov kev txwv qhov kub thiab txias yog qhov tseem ceeb rau nag lossis daus-txoj kev ntxiv dag zog, tsis yog cov hlau alloy qhov chaw chemistry.
Q3: Puas yog Inconel 625 sib nqus?
Tsis yog. Inconel 625, zoo li feem ntau nickel-raws li superalloys nrog lub ntsej muag-centered-cubic (austenitic) crystal structure, tsis yog-magnetic (paramagnetic). Cov cuab yeej no tuaj yeem cuam tshuam rau qee qhov kev siv sensor thiab ntsuas ntsuas ze ze ntawm cov khoom.
Q4: Inconel 625 piv rau titanium alloys rau kub -section daim ntawv thov li cas?
Titanium alloys, txawm tias siab tshaj - kub hloov pauv, feem ntau txwv rau kev pabcuam kub hauv qab li ntawm 550-600℃vim muaj kev txhawj xeeb oxidation thiab embrittlement. Rau 800-1100℃qhov kub thiab txias ntau yam cuam tshuam rau cov khoom siv hluav taws xob thiab cov pa tawm, nickel-raws li superalloys xws li Inconel 625 yog tib txoj kev xaiv hlau, nrog titanium tshwj tseg rau cov cua txias compressor-section Cheebtsam.
Q5: Yuav ua li cas melting xyaum yog feem ntau yuav tsum tau rau aerospace-qib Inconel 625?
Aerospace-qib Inconel 625 bar thiab forging Tshuag feem ntau yog tsim los ntawm lub tshuab nqus tsev induction melting ua raws li lub tshuab nqus tsev arc remelting (VIM-VAR) lossis electroslag remelting (ESR) rau cov ntawv thov tshaj plaws, tshwj xeeb tshaj yog cov khoom sib hloov. Cov txheej txheem no txo cov ntsiab lus suav nrog thiab txhim kho kev ua haujlwm qaug zog piv rau cov qauv huab cua-melted los yog argon-oxygen-decarburization (AOD) cov khoom ua tiav, uas tej zaum yuav siv tau rau cov khoom tsis zoo li qub xws li ducting thiab brackets.
