Duplex stainless hlauthiab304 stainless hlau yog ob hom stainless hlau nrog ntau yam khoom thiab kev siv. Qhov sib txawv tseem ceeb yog xav txog cov tshuaj muaj pes tsawg leeg, microstructure, txhua yam khoom, corrosion kuj, nqi, thiab daim ntawv thov. Cov hauv qab no yog cov ncauj lus kom ntxaws sib piv:
Tshuaj muaj pes tsawg leeg
Los ntawm cov tshuaj muaj pes tsawg leeg pom, cov yam ntxwv tseem ceeb ntawm 304 stainless hlau yog tias nws tso siab rau nickel los tswj nws cov qauv austenitic, tsis muaj molybdenum (Mo) ntxiv. Cov yam ntxwv tseem ceeb ntawm duplex stainless hlau (xws li 2205) yog siab chromium, ntxiv molybdenum, thiab nitrogen, nrog cov ntsiab lus qis nickel. Cov nram qab no yog cov lus sib xyaw ntawm 2205 duplex stainless hlau thiab 304 stainless hlau:
| Lub ntsiab | Chromium (Cr) | Nickel (Ni) | Molybdenum (hli) | Nitrogen (N) | Cov pa roj carbon (C) | Hlau (Fe) |
| 2205 | 21–23% | 4.5–6.5% | 2.5–3.5% | 0.14–0.20% | Tsawg dua lossis sib npaug li 0.03% | Tshuav |
| 304 | 18–20% | 8–10.5% | Tsawg dua lossis sib npaug li 0.75% | Tsawg dua lossis sib npaug li 0.10% | Tsawg dua lossis sib npaug li 0.08% | Tshuav |
Microstructure
- Duplex stainless hlau50% ferrite + ~ 50% austenite. Cov qauv duplex no muab lub zog siab thiab ua haujlwm zoo heev rau chloride kev nyuaj siab corrosion cracking.
- 304 stainless hlau: Qhov no austenitic stainless hlau muaj feem ntau ntawm ib theem austenite (tsis muaj ferrite ntawm chav tsev kub). Nws muaj ductility zoo heev, formability, thiab weldability, tab sis muaj kev cuam tshuam ntau rau kev ntxhov siab corrosion cracking nyob rau hauv ib puag ncig chloride.
Mechanical Properties
Nyob rau hauv cov nqe lus ntawm txhua yam khoom, lub zog tawm los ntawm duplex steel yog ntau tshaj ob zaug ntawm 304, thiab nws cov load - bearing muaj peev xwm muaj zog dua; 304 muaj elongation ntau dua, uas txhais tau tias zoo formability.
| Khoom | Yield zog (MPa) | Tensile zog (MPa) | Elongation (%) | Hardness (HB) |
| 2205 | ~450–550 | ~650–800 | 25–30 | ~250 |
| 304 | ~200–250 | ~500–600 | 40–60 | ~150–160 |
Corrosion Resistance
Duplex stainless hlau
Muab superior corrosion kuj nyob rau hauv hnyav ib puag ncig. Nws cov molybdenum thiab nitrogen cov ntsiab lus muab kev ua haujlwm siab rau chloride pitting thiab crevice corrosion, thiab nws tsis kam rau kev ntxhov siab corrosion cracking (SCC) deb tshaj li ntawm 304. Nws ua tau zoo heev nyob rau hauv tshuaj thiab marine ib puag ncig.
304 stainless hlau
Muaj kev tiv thaiv corrosion zoo heev hauv huab cua, dej tshiab, thiab qhov chaw me me (xws li kev sib cuag zaub mov), tab sis muaj kev cuam tshuam rau pitting corrosion nyob rau hauv siab -cov dej ntsev.
Nqi
- Duplex stainless hlau:Nws cov ntsiab lus alloy siab (Mo thiab N) ua rau ntau dua rau -kilogram raw khoom nqi. Txawm li cas los xij, nws lub zog siab dua tso cai rau txo cov khoom tuab, yog li txo cov nqi tag nrho hauv kev siv cov qauv.
- 304 stainless hlau:Vim nws cov ntsiab lus siab nickel (8% -10.5%) thiab tus nqi siab ntawm nickel (kwv yees li $ 20,000 ib tuj), nws cov nqi cuam tshuam los ntawm cov nqi npib tsib xee, ua rau cov nqi siab thiab tsis ruaj khov.
Daim ntawv thov
| Duplex Stainless hlau | 304 Stainless hlau |
| Offshore roj & roj platforms | Cov khoom siv hauv chav ua noj, cov khoom siv ua zaub mov |
| Marine ib puag ncig | Lub tsev facades, railings, thiab cov khoom dai kom zoo nkauj |
| Cov khoom siv tshuaj ua haujlwm | Cov thawv ntim tshuaj rau qhov chaw me me |
| Pulp & ntawv digesters | Thaum tshav kub kub exchangers (tsis yog -chloride tej yam kev mob) |
| Lub tank cia rau kev tawm tsam hnyav | Cov kav dej hauv tsev |
Xaus
Yog tias koj xav tau lub zog ntau dua, txhim kho cov tshuaj chloride corrosion, thiab SCC tsis kam, duplex stainless hlau yog ib qho kev xaiv zoo dua (tshwj xeeb tshaj yog nyob rau hauv marine lossis tshuaj ib puag ncig). Yog tias koj xav tau kev yooj yim ntawm kev tsim, zoo siab - qhov kub thiab txias, thiab tus nqi qis, 304 feem ntau yog qhov kev xaiv. Raws li cov chaw tsim khoom steel yeeb nkab nrog ntau tshaj 20 xyoo ntawm kev paub,TORICHxyuas kom koj tau txais cov khoom zoo.