Hydrogen yog cov roj ntawm lub neej yav tom ntej - tab sis nws kuj yog ib qho ntawm feem tsis zam txim rau cov khoom siv hlau. Tsis zoo li cov roj, cov pa roj carbon monoxide, lossis txawm tias carbon dioxide, cov roj hydrogen tsis tsuas yog corrode hlau phab ntsa ntawm tus nqi kwv yees. Nws ua ib yam dab tsi ntau txaus ntshai: nws cuam tshuam cov hlau cov qauv siv lead ua, hloov cov kev sib raug zoo ntawm cov atoms, thiab hloov cov ntaub, tawv stainless hlau mus rau hauv cov khoom nkig uas tuaj yeem tawg zoo li iav - yam tsis muaj lus ceeb toom. Qhov tshwm sim no hu ua hydrogen embrittlement (HE), thiab nws yog ib qho tseem ceeb tshaj plaws ntawm cov khoom siv tsis ua haujlwm hauv kev lag luam hydrogen.
Austenitic stainless hlau(304L, 316L) yog cov feem ntau HE-cov qib stainless hlau tiv taus, tab sis lawv tsis tiv thaiv kab mob - lawv raug txwv rau qis- siab hydrogen gas (tsawg dua lossis sib npaug li 1 MPa) saum 60℃ib ASME B31.12. Rau siab -siab hydrogen cia thiab thauj (ntau tshaj 1 MPa), nickel alloys (Inconel 625, Alloy 825) yuav tsum tau. Duplex thiab ferritic stainless hlau feem ntau tsis haum rau kev pabcuam hydrogen.
Raws li lub ntiaj teb kev sib tw los tsim cov chaw nres tsheb hydrogen, cov chaw tsim hluav taws xob ntsuab hydrogen, thiab cov kav dej hydrogen, cov kws tsim khoom thiab pab pawg muag khoom ntsib cov lus nug tseem ceeb: cov qib stainless hlau twg tuaj yeem tiv thaiv hydrogen ntawm qhov kub thiab txias ntawm lawv daim ntawv thov tshwj xeeb? Cov lus teb tsis yooj yim - 304, 316, 321, 347, 430, 2205, thiab 2507 txhua tus teb sib txawv heev rau hydrogen, thiab xaiv qib tsis raug tuaj yeem txhais tau tias muaj kev puas tsuaj loj hauv lub hlis, tsis yog xyoo. Phau ntawv qhia no muab cov lus teb kom tiav, kom muaj nuj nqis.
Yuav ua li cas Hydrogen Embrittles Stainless hlau
Hydrogen embrittlement tshwm sim thaum hydrogen atoms (tsis yog molecules) nkag mus rau hauv cov hlau tsis huv thiab sib sau ua ke ntawm cov teeb meem sab hauv, tsim kom muaj lub siab loj heev uas pib tawg tawg - txo tensile ductility ntawm ~ 60% mus rau qis dua 10% thiab ua rau tam sim ntawd, kev puas tsuaj puas tsuaj uas tsis muaj cov yas deformation.
Hydrogen gas (H₂) ntawm chav tsev kub yog ruaj khov - H₂ molecules tsis nkag mus rau hlau. Dab tsi nkag mus yog atomic hydrogen (H), uas tshwm sim thaum H₂ molecules dissociate ntawm cov hlau nto, txheej txheem uas tshwm sim spontaneously: (1) ntawm qhov kub siab (siab tshaj 200 degree, thermal dissociation ua qhov tseem ceeb); (2) nyob rau hauv siab (hydrogen siab nce tus nqi ntawm nto adsorption); (3) nyob rau hauv lub xub ntiag ntawm hydrogen sulfide (H₂S ua raws li ib tug catalyst, dramatically accelerating hydrogen atom tiam ntawm cov hlau nto - ib tug tshwm sim hu ua "hydrogen permeation" uas yog ib qho tseem ceeb nyob rau hauv qaub roj thiab offshore hydrogen daim ntaub ntawv); (4) thaum lub sij hawm electrochemical txheej txheem xws li electroplating, cathodic tiv thaiv, los yog acid tu (cov txheej txheem no tsim atomic H ncaj qha rau ntawm cov hlau nto).
Thaum atomic hydrogen nkag mus rau hauv stainless hlau nto, nws diffuses los ntawm crystal lattice. Hydrogen atoms yog me me - lawv tsiv nrawm los ntawm cov hlau -nickel-chromium matrix. Tus nqi diffusion nyob ntawm cov qauv siv lead ua: austenite (lub ntsej muag-centered cubic, FCC, pom nyob rau hauv 304/316/321/347) muaj qhov tsis tshua muaj hydrogen diffusion tus nqi (D ≈ 10⁻¹² m² / s) thiab siab hydrogen solubility (cuam hydrogen hauv lattice). Ferrite (lub cev-centered cubic, BCC, pom nyob rau hauv 430 thiab nyob rau hauv lub ferrite theem ntawm duplex 2205/2507) muaj ib tug siab hydrogen diffusion tus nqi (D ≈ 10⁻¹¹ m² / s - txog 10x sai) thiab tsis tshua muaj hydrogen solubility ntawm hydrogen sai. Qhov sib txawv ntawm cov qauv no yog qhov laj thawj tseem ceeb ntawm austenitic stainless hlau tiv taus HE zoo dua qib ferritic lossis duplex.
Plaub Hydrogen Embrittlement Mechanisms hauv Stainless Hlau
Hydrogen embrittlement nyob rau hauv stainless hlau ua hauj lwm los ntawm plaub ib txhij mechanisms - hydrogen-enhanced decohesion (HEDE), adsorption-induced dislocation emission (AIDE), lub siab txoj kev xav, thiab hydride tsim - tag nrho cov uas txo ductility thiab lub zog, tab sis nyob rau hauv sib txawv. Cov txheej txheem tseem ceeb nyob ntawm cov alloy muaj pes tsawg leeg thiab kev pabcuam kub.
|
Mechanism |
Nws ua haujlwm li cas |
Qhov cuam tshuam Stainless hlau |
Qhov kub thiab txias |
Qhov hnyav |
|
HEDE (Hydrogen{0}}Txhim kho decohesion) |
H atoms txo atomic daim ntawv cog lus lub zog ntawm cov ciam teb nplej thiab theem cuam tshuam, ua kom tawg tawm yooj yim dua raws li cov ciam teb. |
Tag nrho SS; tshwj xeeb tshaj yog raug rau ntawm austenite grain ciam teb nyob rau hauv sensitized 304/316 |
-100℃rau +200 degree |
HIGH - intergranular tawg |
|
AIDE (Adsorption{0}}Induced Dislocation Emission) |
H adsorbed ntawm qhov tawg ua rau txo qis lub zog ntawm qhov chaw, ua rau muaj kev cuam tshuam emission thiab ua kom yooj yim cleavage-zoo li pob txha |
Austenitic SS (304L, 316L) - strain-induced martensite paths |
-50℃rau +100 degree |
MODERATE rau HIGH |
|
Siab Theory (Void/Trap Theory) |
H atoms tsiv mus rau MnS suav nrog, voids, thiab thib ob -theem hais; recombine rau H2 molecules tsim lub siab sab hauv mus txog 1,000 MPa - pib tawg |
Txhua SS nrog kev suav nrog (tshwj xeeb yog MnS hauv tus qauv 304/316); phem dua nyob rau hauv siab - qib Sulfur |
-50℃rau +150 degree |
HIGH - sab hauv cracking ntawm inclusions |
|
Hydride Tsim |
H atoms hnov mob nrog cov ntsiab lus alloying (Ti hauv 321, Nb hauv 347, Cr hauv ferritic SS) los tsim cov hlau hydride theem ntawm cov ciam teb |
321 (Ti-stabilized), 347 (Nb-stabilized), 430 (ferritic Cr alloy) |
150℃txog 400℃(hydride stability ntau) |
MODERATE - interfacial cracking |
[Source] ASM Phau Ntawv Qhia Vol. 11: Kev Ntsuam Xyuas thiab Kev Tiv Thaiv Tsis Ua Haujlwm (2002); San Marchi, C. and Somerday, BP "Technical Reference on Hydrogen Compatibility of Materials" (SAND2008-1163, Sandia National Laboratories, 2008).
Vim li cas Crystal Structure yog tus yuam sij rau HE Resistance
Austenitic stainless hlau (FCC siv lead ua qauv) yog cov hydrogen tshaj plaws -embrittlement- stainless hlau vim: (1) hydrogen diffuses 10x qeeb los ntawm FCC dua li BCC hlau; (2) lub austenite lattice ntxiab hydrogen hauv cov kua dej, ua rau nws txoj kev tsiv mus rau qhov tsis xws luag; (3) cov ntsiab lus siab nickel (8-10% hauv 304/316) ntxiv stabilizes FCC qauv. Ferritic stainless hlau (BCC) thiab duplex steels (uas muaj ~ 50% ferrite) yog qhov muaj feem cuam tshuam rau HE vim tias BCC ferrite yog txoj kev nrawm nrawm rau hydrogen.
The stacking fault energy (SFE) of the austenite phase is also critical. SFE measures the energy required to create a stacking fault (a plane where the regular crystal stacking sequence is interrupted) in the austenite lattice. High SFE austenite (>45 mJ/m²): dislocation cross- plam yog ib qho yooj yim, cov kab nrib pleb propagate los ntawm ductile microvoid coalescence - ntau HE-resistant. Tsawg SFE austenite (< 20 mJ/m²): planar slip predominates, localisation of strain into narrow bands, easier crack initiation - more HE-susceptible.
|
Stainless hlau |
Crystal Structure |
SFE (mJ / m²) |
Cov ntsiab lus (%) |
H Diffusion Rate (tus txheeb ze) |
HE Resistance Rank |
|
304L (S30403) |
FCC (Austenite) |
~45–55 |
8–10.5 |
LOW (lub hauv paus=1x) |
🥇 BEST SS qib |
|
316L (S31603) |
FCC (Austenite) |
~55–70 |
10–14 |
qis dua 304L |
🥇 BEST SS qib |
|
321 (S32100) |
FCC (Austenite) |
~40–50 |
9–12 |
QEEJ |
🥈 GOOD (TiC Risk) |
|
347 (S34700) |
FCC (Austenite) |
~40–50 |
9–12 |
QEEJ |
🥈 GOOD (NbC txaus ntshai) |
|
304 (S30400) |
FCC (Austenite) |
~45–55 |
8–10.5 |
LOW (siab dua C txaus ntshai) |
⚠️ CAUTION (sensitisation) |
|
316 (S31600) |
FCC (Austenite) |
~55–70 |
10–14 |
LOW (siab dua C txaus ntshai) |
⚠️ CAUTION (sensitisation) |
|
2205 (S31803) |
FCC + BCC duplex |
~ 50 (Austenite) |
4.5–6.5 |
HIGH (ferrite=10x sai) |
⚠️ CAUTION (ferrite) |
|
2507 (S32750) |
FCC + BCC duplex |
~ 50 (Austenite) |
6–8 |
HIGH (ferrite=10x sai) |
⚠️ CAUTION (ferrite) |
|
430 (S43000) |
BCC (ferrite) |
N/A |
< 0.5 |
HIGHEST (BCC=ceev) |
❌ Tsis pom zoo |
[Source] SFE values: ASM Handbook Vol. 1 (Properties and Selection: Irons, Steels, and High-Performance Alloys); H diffusion sib piv: San Marchi & Somerday, Sandia SAND2008-1163.
Hydrogen Embrittlement Resistance los ntawm Stainless Steel Qib
316L (UNS S31603) yog qhov zoo tshaj plaws txhua yam -tawm stainless hlau rau qis- siab hydrogen gas kev pabcuam. 304L (UNS S30403) tau txais tab sis muaj me ntsis siab dua HE susceptibility ntawm qhov sib npaug. 321 thiab 347 tsis muaj HE kom zoo dua li ntawm 316L bides / hydrogen carti qhia HE-rhiab interfaces. Duplex 2205/2507 thiab ferritic 430 tsis tsim nyog rau kev pabcuam hydrogen.
|
Qib |
UNS |
C max (%) |
Tsis muaj (%) |
Cr (%) |
Mo (%) |
H₂ Siab Limit |
Min T rau H₂ Siv |
ASME B31.12? |
Cov kua dej H₂ (−253 degree)? |
Zuag qhia tag nrho HE Rating |
|
304L |
S30403 |
0.03 |
8–10.5 |
18–20 |
0 |
~ 1 MPa (10 bar) |
60 degree |
✅ Cov xwm txheej |
✅ YOG |
⭐⭐⭐⭐ ZOO |
|
304 |
S30400 |
0.08 |
8–10.5 |
18–20 |
0 |
Tsis tso cai |
N/A |
❌ Tsis muaj npe |
✅ YOG (tab sis nyiam 304L) |
⭐⭐⭐ CAUTION |
|
316L |
S31603 |
0.03 |
10–14 |
16–18 |
2–3 |
~ 1 MPa (10 bar) |
60 degree |
✅ Cov xwm txheej |
✅ YOG |
⭐⭐⭐⭐⭐ BEST SS |
|
316 |
S31600 |
0.08 |
10–14 |
16–18 |
2–3 |
Tsis tso cai |
N/A |
❌ Tsis muaj npe |
✅ YOG (tab sis nyiam 316L) |
⭐⭐⭐ CAUTION |
|
321 |
S32100 |
0.08 |
9–12 |
17–19 |
0 |
~ 1 MPa (cov ntaub ntawv txwv) |
60 degree |
✅ Cov xwm txheej |
✅ YOG |
⭐⭐⭐⭐ TSEEM CEEB |
|
347 |
S34700 |
0.08 |
9–13 |
17–19 |
0 |
~ 1 MPa (cov ntaub ntawv txwv) |
60 degree |
✅ Cov xwm txheej |
✅ YOG |
⭐⭐⭐⭐ TSEEM CEEB |
|
2205 |
S31803 |
0.03 |
4.5–6.5 |
21–23 |
2.5–3.5 |
< 0.1 MPa (1 bar) |
Ambient |
❌ Tsis muaj npe |
⚠️ DBTT kev txhawj xeeb |
⭐⭐ Tsis pom zoo |
|
2507 |
S32750 |
0.03 |
6–8 |
24–26 |
3–5 |
< 0.1 MPa (1 bar) |
Ambient |
❌ Tsis muaj npe |
⚠️ DBTT kev txhawj xeeb |
⭐⭐ Tsis pom zoo |
|
430 |
S43000 |
0.12 |
< 0.5 |
16–18 |
0 |
< 0.01 MPa |
N/A |
❌ Tsis muaj npe |
❌ TSIS MUAJ (DBTT saum RT) |
⭐ XAV |
[Source] ASME B31.12-2019 Table IV-1 (Hydrogen Piping thiab Tubing Materials). Kev txwv siab thiab kub yog qhov kev pabcuam, tsis txwv cov khoom siv - ib txwm txheeb xyuas nrog qhov project specification. DBTT cov ntaub ntawv: ASM Phau Ntawv Qhia Vol. 1.
Vim li cas qis - Cov Qib Carbon (304L, 316L) Yuav tsum tau ua hauv Hydrogen
Ib txwm qhia 304L thiab 316L - yeej tsis 304 lossis 316 - hauv kev pabcuam hydrogen. Cov pa roj carbon sib txawv (0.03% max vs 0.08% max) tsis yog hais txog corrosion (qhov laj thawj rau qib L), nws yog hais txog hydrogen embrittlement. Cov pa roj carbon ntau dua hauv tus qauv 304/316 nce qhov ceev ntawm chromium carbides (Cr₂₃C₆) ntawm cov ciam teb thaum lub sij hawm vuam los yog siab - kev pabcuam kub. Cov carbide precipitates deplete chromium los ntawm ib puag ncig matrix (sensitisation), tsim chromium -depleted aav uas yog qhov chaw nyiam rau hydrogen tsub zuj zuj thiab grain ciam teb tawg. Qhov 0.03% carbon txwv hauv qib L- tiv thaiv qhov no.
Txoj Cai Engineering 1 -Hauv kev pabcuam hydrogen, ib txwm hais qhia L-qib stainless hlau (304L, 316L). Qhov 0.05% carbon sib txawv ntawm 304 thiab 304L (los yog 316 thiab 316L) txiav txim seb puas yog grain ciam chromium carbides tsim thaum vuam los yog kev pab cuam. Hauv hydrogen, cov carbide - nplua nuj ciam teb yog qhov chaw pib tawg. Txoj cai no siv tau rau TXHUA qhov kev pabcuam hydrogen, tsis hais lub siab lossis qhov kub thiab txias - nws tsis yog -kev sib tham tau rau txhua yam stainless hlau hauv hydrogen.
Dab tsi Txog 321 thiab 347 - Titanium thiab Niobium Stabilized Qib?
321 (titanium{1}}stabilized) thiab 347 (niobium-stabilized) austenitic stainless hlau tsis zoo tshaj 316L hauv kev pabcuam hydrogen. Thaum lawv tawm tsam qhov kev xav tau zoo dua li 304/316, lawv cov titanium carbides (TiC) thiab niobium carbides (NbC) tsim ntxiv thib ob -theem particle/matrix interfaces - thiab hydrogen atoms sib sau ntawm txhua qhov thib ob -theem interfaces. Ntau qhov sib cuam tshuam=ntau qhov chaw hydrogen trapping=siab dua HE. Siv 321/347 tsuas yog qhov siab - qhov kub thiab txias (siab dua 425 degree) yuav tsum tau - tsis yog rau kev pabcuam hydrogen uas 316L yog qhov kev xaiv zoo dua.
Ib daim ntawv thov raug cai rau 321 hauv hydrogen: siab -kub gaseous hydrogen kev pab cuam saum toj 425 degree, qhov twg TiC precipitates muab superior creep zog piv rau 316L. Ntawm cov kub no, hydrogen embrittlement kuj tsis tshua hnyav vim tias qhov kub siab txhawb nqa hydrogen diffusion tawm ntawm lub lattice (thermal desorption). Tab sis rau kev pabcuam hauv qab 425 degree, 316L yog qhov nyiam.
Duplex thiab Ferritic Stainless Steels hauv Hydrogen
Duplex stainless hlau (2205, 2507) muaj ntau dua rau hydrogen embrittlement dua qib austenitic, txawm tias lawv superior chloride kev nyuaj siab corrosion cracking kuj. Lub ferrite theem nyob rau hauv duplex stainless hlau ua raws li ib tug ceev ceev - diffusion txoj kev loj rau hydrogen atoms, thiab hydrogen concentrating nyob rau hauv ferrite txo nws ductility heev - nyob rau hauv ib co kev ntsuam xyuas, ferrite-theem ductility poob los ntawm 60-80% nyob rau hauv hydrogen ib puag ncig. ASME B31.12 tsis sau duplex stainless hlau raws li tau txais rau hydrogen piping. Siv cov qib austenitic lossis nickel alloys hloov.
Qhov teeb meem yog cov duplex microstructure nws tus kheej: kwv yees li 50% austenite (FCC, hydrogen-resistant) thiab 50% ferrite (BCC, hydrogen- susceptible) nyob ib sab. Hydrogen atoms diffusing los ntawm theem ferrite sib sau ua ke ntawm austenite / ferrite theem ciam teb vim austenite muaj hydrogen solubility ntau dua tab sis qis diffusivity - nws ua raws li hydrogen ntxiab. Lub austenite / ferrite interface dhau los ua ib cheeb tsam ntawm cov hydrogen concentrated, txhawb HEDE- hom intergranular tawg raws theem ciam teb. Kev tshawb fawb ntawm 2205 nyob rau hauv siab -siab hydrogen gas (txog 69 MPa) qhia tau hais tias ductility txo qhov tseem ceeb ntawm txhua qhov ntsuas kub (–50℃rau +100℃).
|
Qhov xwm txheej |
304L Ductility Poob |
316L Ductility Poob |
2205 Ductility Poob |
Txhais lus |
|
Gaseous H₂, 1 MPa, 25 degree |
Tsawg (~ 5-10% RA poob) |
Tsawg heev (~ 2-5% RA poob) |
Siab (~ 30-50% RA poob) |
Austenitic SS nyiam |
|
Gaseous H₂, 10 MPa, 25 degree |
Nruab nrab (~ 15-25% RA poob) |
Tsawg (~ 10-15% RA poob) |
Mob hnyav (~ 60-80% RA poob) |
Austenitic yuav tsum tau; duplex ua tsis tau |
|
Gaseous H₂, 1 MPa, 60 degree |
Tsawg heev (< 5% RA loss) |
Tsawg kawg (< 3% RA loss) |
Nruab nrab (~ 25-40% RA poob) |
Kub tiv thaiv austenitic; tsis duplex |
|
Liquid H₂, -253 degree, 1 atm |
Tsawg (ntshiab H2, tsis muaj kev sib cais) |
Tsawg kawg (ntshiab H2) |
Tsis paub / tsis ntsuas |
Siv austenitic rau kua H2 |
|
H₂ + H₂S (qaub), txhua qhov siab |
Nruab Nrab HE (H₂S nrawm H nkag) |
Moderate HE |
Severe HE (ferrite + H₂S) |
Nickel alloy yuav tsum tau (ISO 15156) |
[Source] San Marchi, C. et al. "Hydrogen Compatibility ntawm Austenitic Stainless Steel Hom 316 thiab 316L," Sandia National Laboratories SAND2007-7994 (2008). Duplex 2205 HE data: Somerday, BP et al., ASTM STP 1517 (2011).
Ferritic Stainless Steel (430) hauv Hydrogen - Kev txwv hnyav
Ferritic stainless hlau 430 (UNS S43000) yuav tsum tsis txhob siv rau hauv cov kev pabcuam roj hydrogen siab ntawm qhov siab tshaj 0.01 MPa (0.1 bar). Kev sib xyaw ua ke ntawm BCC siv lead ua qauv (siab H diffusion), cov ntsiab lus nickel tsawg heev (< 0.5%), and the absence of any FCC phase means hydrogen atoms diffuse rapidly through 430 and accumulate at chromium carbide grain boundaries. Additionally, 430 has a ductile-to-brittle transition temperature (DBTT) above room temperature - meaning it is already brittle at 20°C in the notch-impact test, before any hydrogen exposure. In hydrogen, its ductility drops to essentially zero.
Qhov teeb meem DBTT feem ntau tsis saib xyuas tab sis yog qhov tseem ceeb: tus qauv Charpy V- qhov ntsuas qhov cuam tshuam ntawm 430 qhia qhov cuam tshuam lub zog ntawm tsuas yog ~ 50–60 J ntawm 20℃(chav kub), piv rau 200–300 J rau 304L / 316L ntawm qhov kub thiab txias. Ntawm 0 degree, 430 cuam tshuam lub zog poob rau ~ 20–30 J - ciam teb. Ntawm -20℃(muaj peev xwm nyob rau hauv kev pab cuam hydrogen txias), 430 ua nkig. Hydrogen raug hloov mus rau DBTT nce siab los ntawm 30–50℃- txhais tau tias 430 feem uas tsis tshua pom zoo ntawm 20℃yuav txaus ntshai nkig ntawm 30℃tom qab hydrogen raug. Qhov no yog vim li cas 430 raug txwv nyob rau hauv hydrogen cia thiab thauj cov lej.
Standards thiab Codes
ASME B31.12-2019 yog tus qauv tsim qauv rau cov kav dej hydrogen. Nws txwv austenitic stainless hlau (304L, 316L, 321, 347) rau gaseous hydrogen kev pab cuam ntawm lub siab tsis tshaj li ntawm 1 MPa (1,000 kPa, ~ 10 bar) thiab kub siab tshaj 60 degree. Qhov no yog tus qauv txwv tshaj plaws rau stainless hlau hauv hydrogen, thiab nws yog qhov yuav tsum tau ua raws li qhov tsawg kawg nkaus rau txhua qhov kev siv hydrogen piping project hauv Asmeskas thiab feem ntau thoob ntiaj teb kev lag luam.
|
Alloy |
UNS |
ASME B31.12 Sau npe? |
Max H₂ Siab |
Kub kub |
Sau ntawv |
|
304L stainless hlau |
S30403 |
✅ YOG |
~ 1 MPa (10 bar) |
60℃(140℃F) |
Tus nqi qis tshaj austenitic H2 qib |
|
316L stainless hlau |
S31603 |
✅ YOG |
~ 1 MPa (10 bar) |
60℃(140℃F) |
ZOO TSHAJ PLAWS SS rau H2 - Mo txhim kho kev tiv thaiv |
|
321 stainless hlau |
S32100 |
✅ YOG |
~ 1 MPa (10 bar) |
60℃(140℃F) |
Only if high-T strength (>425 degree) xav tau |
|
347 stainless hlau |
S34700 |
✅ YOG |
~ 1 MPa (10 bar) |
60℃(140℃F) |
Only if high-T strength (>425 degree) xav tau |
|
304 stainless hlau |
S30400 |
❌ TSIS |
N/A |
N/A |
Tsis teev - siv 304L |
|
316 stainless hlau |
S31600 |
❌ TSIS |
N/A |
N/A |
Tsis teev - siv 316L |
|
2205 duplex stainless hlau |
S31803 |
❌ TSIS |
N/A |
N/A |
Tsis muaj npe - Nws txhawj xeeb |
|
2507 super duplex |
S32750 |
❌ TSIS |
N/A |
N/A |
Tsis muaj npe - Nws txhawj xeeb |
|
430 ferritic stainless hlau |
S43000 |
❌ TSIS |
N/A |
N/A |
Tsis muaj npe - HE + DBTT kev txhawj xeeb |
|
Ib 625 |
N06625 |
✅ YOG (ntawm ISO 15156) |
Tsis txwv |
-196 degree |
Qhov zoo tshaj plaws rau siab -siab H2 (siab dua 1 MPa) |
|
alloy 825 |
N08825 |
✅ YOG (ntawm ISO 15156) |
Tsis txwv |
-196 degree |
Tus nqi -nickel alloy zoo rau H2 |
[Source] ASME B31.12-2019, Table IV-1 (Hydrogen Piping thiab Tubing Materials). Lus Cim: 1 MPa ≈ 10 bar ≈ 145 psi. Ib txwm txheeb xyuas cov ntawv tam sim no ntawm ASME B31.12 tiv thaiv qhov project specification.
ISO 15156 / NACE MR0175
ISO 15156 tsis tsim nyog rau austenitic lossis duplex stainless hlau rau kev pabcuam qaub - uas yog, ib puag ncig uas muaj ob qho tib si hydrogen sulfide (H₂S) thiab hydrogen. Hauv cov av qaub thiab cov kua dej tawm sab nraud, hydrogen tam sim no yog cov khoom siv los ntawm cov tshuaj tiv thaiv corrosion (H₂S + Fe → FeS + 2H), thiab cov atomic hydrogen no nkag mus rau cov hlau los ntawm H₂S-catalysed txoj kev ntawm tus nqi 10–100x siab dua hauv cov pa ntshiab hydrogen. Rau cov kev pabcuam qaub hydrogen, nickel alloys (Inconel 625, Alloy 825) tsim nyog raws li ISO 15156 Table 5 yuav tsum tau - tsis yog stainless hlau.
Qhov tseem ceeb sib txawv: cov kev pab cuam hydrogen ntshiab (hydrogen refueling chaw nres tsheb, hydrogen pipeline) → siv ASME B31.12 → austenitic stainless hlau txais tau nyob rau hauv kev txwv. qaub hydrogen / H₂S-cov kev pabcuam hydrogen (tawm sab nrauv tsim cov kua dej, lub qhov dej qaub qaub, cov dej ua kua hydrogen nrog H₂S) → siv ISO 15156 → nickel alloys xav tau, stainless hlau tsis tau teev tseg. Lub ciam teb ntawm ob pawg no yog H₂S ib nrab siab siab tshaj 0.05 psia (0.0003 MPa) - saum toj no qhov pib, H₂S catalyses hydrogen nkag thiab ua rau nws nrawm heev.
API 620 / API 650 - Hydrogen Storage Tanks
API 620 Annex Q tswj kev tsim cov khoom qis -siab hydrogen cia nkoj. Austenitic stainless hlau (304L, 316L) tau tso cai rau cov kua hydrogen cia (-253 degree) thiab qis-siab gaseous hydrogen cia (txog ~ 1.7 MPa) rau API 620. Rau siab -siab gaseous hydrogen cia (siab dua 1.7 MPa), cov ntaub ntawv siab API 2 rau 1.7 MPa los yog 3. xaiv los ntawm ASME B31.12. API 650 npog atmospheric- tso tsheb hlau luam siab - tsis muaj feem xyuam rau cov pa hydrogen.
Cov lus nug nquag
Q: 304 stainless hlau puas tuaj yeem siv rau hauv kev pabcuam hydrogen?
A: Txheem 304 stainless hlau (UNS S30400) tsis pom zoo rau kev pabcuam hydrogen. Nws cov ntsiab lus carbon (txog li 0.08%) ua rau nws raug rau rhiab heev (grain ciam teb chromium carbide nag lossis daus) thaum vuam los yog siab -kev pab kub, uas tsim chromium-depleted zones uas yog qhov zoo tshaj plaws pib tawg qhov chaw nyob rau hauv hydrogen raug. Siv 304L (UNS S30403, carbon Tsawg dua lossis sib npaug li 0.03%) hloov. Txawm tias 304L yog txwv rau kwv yees li 1 MPa thiab kub siab tshaj 60℃ib ASME B31.12. Rau siab dua, hloov mus rau 316L (ib yam txwv) lossis Inconel 625 (tsis txwv qhov siab).
Q: Dab tsi yog hydrogen embrittlement pib rau 316L stainless hlau?
A: 316L stainless hlau (UNS S31603) tuaj yeem siv tau rau kev pabcuam roj av txog li 1 MPa (10 bar) thiab kub siab tshaj 60 degree, raws li teev hauv ASME B31.12-2019 Table IV-1. Tshaj 1 MPa lossis qis dua 60 degree, 316L qhia tau tias ntsuas qhov poob qis - elongation tuaj yeem poob ntawm tus qauv ~ 60% mus rau 30-40% hauv high-pressure hydrogen. Molybdenum (2–3%) hauv 316L muab qhov zoo dua me ntsis ntawm 304L hauv kev pabcuam hydrogen, feem ntau los ntawm kev txhim kho kev tiv thaiv rau hydrogen-pab nto tawg. Rau hydrogen pressures siab tshaj 1 MPa, Inconel 625 (UNS N06625) yog tus qauv hloov kho, tsim nyog rau unlimited siab thiab kub hauv hydrogen kev pab raws li ISO 15156.
Q: Vim li cas duplex stainless hlau (2205, 2507) tsis pom zoo rau hydrogen?
A: Duplex stainless hlau 2205 (UNS S31803) thiab 2507 (UNS S32750) muaj ntau dua rau hydrogen embrittlement dua li austenitic qib 304L lossis 316L, txawm tias lawv cov tshuaj chloride zoo dua corrosion cracking kuj. Cov theem ferrite (lub cev-centered cubic crystal qauv, ~ 50% ntawm microstructure) muaj hydrogen diffusion tus nqi kwv yees li 10x siab dua austenite - hydrogen atoms haiv neeg los ntawm ferrite thiab sib sau ntawm austenite / ferrite theem ciam teb. Cov ciam teb theem no dhau los ua qhov chaw pib tawg nyob rau hauv qhov raug hydrogen. Cov kev tshawb fawb pom tias 2205 ductility poob ntawm 60-80% nyob rau hauv siab -siab hydrogen (69 MPa), piv rau 5-25% rau 316L nyob rau hauv tib yam. ASME B31.12 tsis sau npe duplex stainless hlau raws li qhov siv tau rau hydrogen piping - austenitic stainless hlau lossis npib tsib xee alloys yuav tsum tau siv los hloov.
Q: Dab tsi stainless hlau yog qhov zoo tshaj plaws rau cov kua hydrogen cia ntawm -253 degree?
A: 304L thiab 316L austenitic stainless hlau yog cov khoom siv rau cov kua hydrogen cia (-253 degree, kwv yees li 1 atm). Nyob rau ntawm qhov kub thiab txias, cov kua hydrogen yog qhov tseem ceeb ntshiab molecular H₂ - tsis muaj atomic hydrogen dissociation tshwm sim, tshem tawm cov thawj embrittlement mechanism. Ob leeg 304L thiab 316L muaj qhov zoo heev Charpy V-notch cuam tshuam toughness ntawm -253℃(feem ntau 150-250 J, deb tshaj 41 J yam tsawg kawg nkaus rau PSL-2 kev pabcuam), thiab lawv tau tso cai rau cov kua hydrogen cia rau ib qho ASME VIII Division 1 thiab API 620 AnnexOT stainless hlau yuav tsum siv cov khoom siv hlau tsis muaj steel Q. - nws cov ductile-rau-brittle hloov kub (DBTT) yog siab dua chav tsev kub, ua rau nws nkig ua ntej yuav raug hydrogen.
Q: Dab tsi cov qauv tswj hwm stainless hlau hauv kev pabcuam hydrogen?
A: Peb cov qauv yuav tsum tau ua rau stainless hlau hauv kev pabcuam hydrogen: (1) ASME B31.12-2019 - Hydrogen Piping thiab Tubing Code: teev cov khoom siv tau (304L, 316L, 321, 347 austenitic SS) nrog rau siab thiab kub txwv; (2) ISO 15156 / NACE MR0175 - Cov khoom siv rau H₂S-cov kev pabcuam kabmob: TSIS TXHOB sau cov austenitic lossis duplex stainless hlau; Nickel alloys (Inconel 625, Alloy 825) yog cov khoom tsim nyog rau kev pabcuam qaub hydrogen; (3) API 620 Annex Q / ASME VIII Division 1 - Cov tso tsheb hlau luam thiab cov hlab ntsha siab: tswj cov khoom siv rau hydrogen cia tank. Nco ntsoov txheeb xyuas tus qauv tsim nyog rau koj qhov kev txiav txim siab tshwj xeeb thiab daim ntawv thov.
Q: Vim li cas hydrogen ua stainless hlau nkig?
A: Hydrogen embrittlement tshwm sim nyob rau hauv peb theem: (1) Hydrogen gas (H₂ molecules) dissociates rau hauv atomic hydrogen (H) ntawm stainless hlau nto - qhov no tshwm sim nyob rau hauv siab kub, siab kub, los yog nyob rau hauv lub xub ntiag ntawm H₂S; (2) Atomic hydrogen atoms diffuse mus rau hauv stainless hlau siv lead ua lattice - lawv tsiv los ntawm cov hlau-nickel-chromium matrix thiab sib sau ntawm cov chaw tsis xws luag: grain ciam teb, MnS inclusions, thiab thib ob-theem particle interfaces; (3) Ntawm qhov chaw ntxiab no, ob lub atom hydrogen recombine tsim ib H₂ molecule. Cov H₂ molecules tsis tuaj yeem khiav tawm ntawm qhov tsis muaj qhov tsis pom kev, tsim cov pa hauv nruab nrog siab txog 1,000 MPa - sib npaug rau 10,000 cua. Lub siab no ua rau cov hlau tawg raws li cov ciam teb (HEDE mechanism). Qhov tshwm sim: ductility poob los ntawm ~ 60% elongation mus rau qis dua 10%; qhov kawg tensile zog poob; thiab tawg ua nkig - tsis muaj yas deformation los ceeb toom ntawm kev ua tsis tiav. Qhov no yog vim li cas hydrogen embrittlement yog qhov txaus ntshai tshwj xeeb: nws tsis ceeb toom ua ntej kev puas tsuaj puas tsuaj.
