Q1: Cov tshuaj muaj pes tsawg leeg ntawm Hastelloy B phaj yog dab tsi, thiab nws txawv li cas tom qab B-series alloys?
A:Hastelloy B (feem ntau hu ua thawj Hastelloy B lossis UNS N10001) yog tus thawj coj ntawm B-2 thiab B-3 alloys niaj hnub. Nws cov nominal tshuaj muaj pes tsawg leeg yog kwv yees li:Nickel (sib npaug, feem ntau ntau dua lossis sib npaug li 60%), Molybdenum 26.0–30.0%, Hlau 4.0–6.0%, Chromium Tsawg dua lossis sib npaug li 1.0%, Manganese Tsawg dua lossis sib npaug li 1.0%, Silicon Tsawg dua lossis sib npaug li 1.0%, Carbon Tsawg dua lossis sib npaug 0., thiab taug qab tus nqi ntawm vanadium, cobalt, thiab tungsten. Piv rau tom qab B-series alloys, qhov sib txawv tseem ceeb tshaj plaws yog:
Cov ntsiab lus hlau ntau dua(4–6% hauv B vs. Tsawg dua lossis sib npaug li 2.0% hauv B-2 thiab 1.5–3.0% hauv B-3)
Cov pa roj carbon ntau dua(Less tshaj lossis sib npaug rau 0.05% hauv B vs. Tsawg dua lossis sib npaug rau 0.02% hauv B-2 thiab Tsawg dua lossis sib npaug rau 0.01% hauv B-3)
Siab dua silicon(Less tshaj lossis sib npaug rau 1.0% hauv B vs. Tsawg dua lossis sib npaug rau 0.10% hauv B-2 thiab B-3)
Cov qib siab dua ntawm cov hlau, carbon, thiab silicon ua rau Hastelloy Bntau susceptible rau intermetallic theem nag lossis daus(Ni₄Mo, Ni₃Mo) dua li B-2, thiab ntau dua li B-3. Tsis tas li ntawd, cov ntsiab lus carbon ntau dua ua rau muaj kev pheej hmoo ntawm carbide nag lossis daus ntawm cov ciam teb, uas tuaj yeem ua rau muaj kev cuam tshuam ntawm intergranular corrosion hauv qee qhov chaw.
Hastelloy B tau tsim nyob rau hauv nruab nrab xyoo pua 20th thiab tau dav siv rau kev pabcuam hydrochloric acid. Txawm li cas los xij, nws cov thermal stability tsis zoo thaum lub sij hawm vuam thiab kub sib sau ua rau tsis tshua muaj tshwm sim vim embrittlement thiab kev ntxhov siab-corrosion tawg. Cov kev txwv no tau tsav txoj kev loj hlob ntawm B-2 (qis carbon thiab silicon) thiab tom qab B-3 (ntxiv cov ntsiab lus zoo hlau thiab thermal stability). Niaj hnub no, thawj Hastelloy B phaj yogntau dhau lawmthiab tau hloov los ntawm B-2 (uas nws tus kheej tau hloov los ntawm B-3) rau txhua yam kev siv. Txawm li cas los xij, cov cuab yeej qub txeeg qub teg uas tsim los ntawm Hastelloy B tseem muaj nyob hauv cov nroj tsuag tshuaj qub, cov kab hlau pickling, thiab cov chaw siv tshuaj.
Q2: Hauv daim ntawv thov qub txeeg qub teg twg tseem yuav ntsib Hastelloy B phaj, thiab dab tsi yog qhov pheej hmoo ntawm kev siv txuas ntxiv?
A:Txawm hais tias Hastelloy B phaj tsis yog tsim los ntawm cov mills loj (xws li, Haynes International tau txiav tawm thawj B hauv kev pom zoo ntawm B-2 hauv xyoo 1980s, thiab B-2 tam sim no tau raug txiav tawm rau B-3), cov cuab yeej cuab tam qub txeeg qub teg ntawm B phaj tseem tuaj yeem pom hauv:
Laus hydrochloric acid cia tanks thiab reactors- Cov nroj tsuag tshuaj ua ntej 1985 feem ntau siv Hastelloy B rau HCl kev pabcuam. Qee qhov ntawm cov hlab ntsha no tseem ua haujlwm, tshwj xeeb tshaj yog nyob rau hauv qhov tseem ceeb, tsis tshua muaj kub (<80°C / 175°F), low‑pressure applications.
Pickling tanks hauv steel mills- Ntau cov kab hlau pickling tau teeb tsa hauv xyoo 1960-1970s tau siv Hastelloy B phaj rau tank liners, cua sov coils, thiab npog. Cov no tau hloov pauv lossis hloov pauv ntau, tab sis qee qhov tseem ceeb B cov khoom tseem tuaj yeem ua haujlwm.
Pharmaceutical reactors- Qee qhov qub batch reactors rau HCl-raws li syntheses tau tsim los ntawm Hastelloy B. Cov no feem ntau raug txiav tawm vim yog cov kev cai nruj dua thiab kev huv huv.
Cov cuab yeej tshawb fawb hauv chav kuaj- Cov nroj tsuag tsav tsheb thiab cov chaw sim ntsuas hluav taws xob los ntawm nruab nrab xyoo pua 20th tuaj yeem muaj cov khoom Hastelloy B.
Kev pheej hmoo ntawm kev txuas ntxiv siv cov cuab yeej cuab tam Hastelloy B phaj suav nrog:
Intermetallic theem embrittlement- Txawm hais tias tus thawj fabrication tau ua tib zoo, ntau xyoo ntawm thermal cycling (xws li, cua sov thiab txias ntawm batch reactors) yuav maj mam precipitate Ni₄Mo thiab Ni₃Mo theem, txo ductility thiab ua rau lub phaj muaj nkig puas. Qhov no yog qhov txaus ntshai tshwj xeeb vim nws tshwm sim yam tsis muaj cov cim ceeb toom pom.
Carbide nag lossis daus- Cov ntsiab lus carbon ntau dua (tsawg dua lossis sib npaug li 0.05%) tuaj yeem ua rau cov qoob loo ntawm cov ciam teb carbide tsim nyob rau hauv cov cheeb tsam uas muaj kev kub ntxhov ntawm cov welds, txawm tias qhov kub nruab nrab (400-600℃/ 750-1110℃F). Qhov no ua rau intergranular corrosion hauv HCl kev pabcuam.
Txo corrosion kuj piv rau niaj hnub alloys- Hastelloy B muaj qis dua molybdenum me ntsis (26-30%) thiab cov hlau ntau dua B-2 / B-3, ua rau cov nqi qis dua corrosion hauv cov concentrated HCl, tshwj xeeb tshaj yog nyob rau qhov kub siab tshaj 80 degree.
Kev kho nyuaj- Vuam ntawm cov cuab yeej cuab tam B phaj yog qhov nyuaj heev vim tias lub hauv paus hlau yuav raug embrittled, thiab cov ntsiab lus carbon / silicon siab ua rau cov welds tshiab tuaj yeem tawg. Ntau fabricators tsis kam welding ntawm thawj B.
Kev pom zoo:Rau cov cuab yeej cuab tam Hastelloy B, kev kuaj tsis tu ncua (ultrasonic thickness xyuas, dye penetrant ntawm welds) yog qhov tseem ceeb. Yog tias pom cov phab ntsa tseem ceeb los yog tawg, cov khoom yuav tsum tau hloov nrog B-3 phaj, uas yog tag nrho sib xws nyob rau hauv cov nqe lus ntawm corrosion kuj thiab feem ntau yuav welded rau B Cheebtsam uas twb muaj lawm nrog cov txheej txheem hloov tsim nyog.
Q3: Dab tsi yog qhov tseem ceeb welding thiab fabrication cov nyom tshwj xeeb rau thawj Hastelloy B phaj?
A:Vuam thiab fabricating thawj Hastelloy B phaj yog qhov nyuaj dua rau B-2, thiab loj heev ntau dua li B-3. Cov kev sib tw yog los ntawm cov hlau alloy siab (tsawg dua lossis sib npaug li 0.05%), siab silicon (tsawg dua lossis sib npaug li 1.0%), thiab cov hlau siab dua (4-6%), tag nrho cov uas txhawb kev sib tshuam thiab carbide nag lossis daus. Cov teeb meem tseem ceeb suav nrog:
1. Kev kub siab heev rau cov nag lossis daus (Ni₄Mo, Ni₃Mo):Cov nag lossis daus kinetics hauv thawj B yog nrawm dua li hauv B-2. Qhov kub thiab txias nyob rau hauv thaj tsam ntawm 600-900℃(1110-1650℃F) txawm tias 30-60 vib nas this tuaj yeem ua rau muaj theem tseem ceeb. Hauv kev vuam, thaj chaw muaj kev kub ntxhov (HAZ) tuaj yeem ncav cuag cov ntsuas kub no rau ob peb feeb, zoo lav qee qhov kev cuam tshuam ntawm embrittlement. Qhov ua rau poob ntawm ductility (elongation tuaj yeem poob ntawm 30% mus rau<2%) leads to stress-relief crackingthaum txias lossis sai tom qab kev pabcuam.
2. Carbide nag lossis daus:Cov ntsiab lus carbon ntau dua ua rau tsim cov chromium-nplua nuj lossis molybdenum-nplua nuj carbides (M₆C, M₂₃C₆) ntawm cov ciam teb thaum lub phaj raug 400-800℃(750-1470℃F). Qhov no rhiab heev ua rau intergranular corrosion nyob rau hauv HCl kev pab cuam, qhov twg cov lis ciam teb corrode preferentially, ua rau lub phaj disintegrate raws lub weld HAZ.
3. Cov txheej txheem vuam uas yuav tsum tau muaj (tseem ceeb heev):Yuav kom txo qis kev puas tsuaj, welders yuav tsum ua raws li cov kev txwv nruj heev:
Cov khoom siv cua sov tsawg dua lossis sib npaug rau 0.8 kJ / mm (Less dua lossis sib npaug rau 20 kJ / hauv)- txawm tias qis dua rau B-2
Interpass kub Tsawg dua los yog sib npaug rau 100℃(212℃F)- qis dua rau B-2
Stringer hlaws txheej txheem nkaus xwb- tsis muaj weaving
Tsis muaj preheat- preheat yuav nce lub sij hawm nyob rau hauv rhiab ntau yam
Matching muab tub lim hlau- ERNiMo-1 (AWS A5.14) is the standard filler for original B, but it is rare stocked today. Qee tus neeg tsim khoom siv ERNiMo-7 (B-2 muab tub lim) los hloov, tab sis qhov no yuav tsum tau ua tib zoo tsim nyog.
4. Kev kho cua sov tom qab vuam (PWHT):Raws li nrog B-2, PWHT yogtsis pom zootshwj tsis yog tias nws yog ib qho kev daws teeb meem tag nrho (1060-1100℃/ 1940-2010℃F) ua raws li cov dej nrawm nrawm. Txawm li cas los xij, tag nrho cov tshuaj annealing ntawm lub nkoj loj fabricated yog feem ntau impractical. Yog li ntawd, feem ntau B phaj welds yog siv nyob rau hauv lub as-welded mob, muaj kev pheej hmoo ntawm yav tom ntej tsis ua hauj lwm.
5. Kub txoj kev:Kub sib sau ntawm B phaj yog tsis tshua muaj sim hnub no vim muaj kev pheej hmoo ntawm intermetallic nag lossis daus. Kev ua kom txias yog nyiam, tab sis yog tias qhov txo qis qis dua 10-15%, yuav tsum muaj kev daws teeb meem tag nrho. Ntau tus fabricators tsuas tsis kam ua haujlwm nrog thawj B phaj.
6. Muaj cov khoom muab tub lim:ERNiMo-1 muab cov hlau tsis yog tsim los ntawm cov chaw muag khoom loj. Hloov nrog B-2 lossis B-3 muab tub lim hlau tuaj yeem tsim cov vuam siv tau rau cov ntaub ntawv tsis tseem ceeb, tab sis qhov tsis sib haum xeeb hauv kev sib xyaw (cov hlau sib txawv thiab cov pa roj carbon ntau) tuaj yeem ua rau galvanic corrosion ntawm lub vuam sib txuas.
Tswv yim tswv yim:Yog tias kho lossis hloov kho cov cuab yeej cuab tam Hastelloy B yog qhov yuav tsum tau ua, txoj hauv kev nyiam yogtxiav tawm qhov puas B seem thiab txuas rau hauv B-3 phaj ntxigsiv B-3 muab tub lim hlau (ERNiMo-11). Txoj kev hloov vuam yuav tsum tsim nyog, suav nrog kev sim nruj (ASTM G28 intergranular corrosion, khoov kuaj, daim ntawv qhia kev nyuaj). Feem ntau, txawm li cas los xij, hloov tag nrho cov khoom nrog B-3 yog qhov zoo dua li kev sim kho qhov qub B.
Q4: Dab tsi yog qhov kev tiv thaiv corrosion thiab kev txwv ntawm Hastelloy B phaj piv rau cov hlau niaj hnub no?
A:Hastelloy B phaj muaj kev tiv thaiv zoo heev rau cov ntshiab hydrochloric acid thiab lwm yam kev txo qis ib puag ncig, tab sis nws qhov kev ua tau zoo yog qis dua B-2 thiab B-3 hauv ntau yam tseem ceeb:
Corrosion kuj nyob rau hauv hydrochloric acid:
| Qhov xwm txheej | Hastelloy B | Hastelloy B-2 | Hastelloy B-3 |
|---|---|---|---|
| 10% HCl, 60℃(140℃F) | <0.05 mm/year | <0.05 mm/year | <0.05 mm/year |
| 20% HCl, boiling (110 degree) | 0.15-0.25 hli / xyoo | 0.10-0.15 hli / xyoo | 0.10-0.15 hli / xyoo |
| 37% HCl, 80℃(175℃F) | 0.30-0.50 hli / xyoo | 0.20-0.30 hli / xyoo | 0.20-0.30 hli / xyoo |
| 10% HCl + 200 ppm Fe³⁺, 80 degree | >2.0mm / xyoo (pitting) | 0.50-1.0 hli / xyoo | 0.50-1.0 hli / xyoo |
Cov hlau thiab cov pa roj carbon ntau dua nyob rau hauv thawj B me ntsis degrade nws cov kev ua tau zoo, tshwj xeeb tshaj yog nyob rau hauv lub xub ntiag ntawm oxidizing impurities (Fe³⁺, Cu²⁺, yaj oxygen). B kuj tseem cuam tshuam rau pitting nyob rau hauv qhov chaw nyob ruaj khov lossis qis qis.
Cov kev txwv (nrog rau tag nrho B-series alloys):
Oxidizing acid nres-B plate yogtsis haum for nitric acid, chromic acid, concentrated sulfuric acid (>90%), los yog ib puag ncig uas muaj oxidizing hom. Corrosion tus nqi tuaj yeem tshaj 5 hli / xyoo.
Intergranular nres- Vim yog nag lossis daus carbide, B phaj tuaj yeem raug kev cuam tshuam ntawm kev sib tsoo hauv thaj chaw kub-tshem ntawm welds, txawm tias qhov kev pabcuam HCl me me. Qhov no tsis tshua muaj teeb meem nrog B-2 thiab B-3 vim lawv cov ntsiab lus qis dua.
Kev txwv kub- Tshaj 150℃(300℃F) hauv cov ntsiab lus HCl, txawm tias B phaj corrodes ntawm tus nqi tsis txaus ntseeg. Rau qhov kub siab dua, tantalum lossis zirconium yuav tsum tau ua.
Cov kev cuam tshuam:Rau cov cuab yeej cuab tam B phaj, qhov tseem ceeb ntawm lub neej tuaj yeem kwv yees los ntawm:
Ntsuas qhov tseeb phab ntsa thickness (ultrasonic kuaj)
Tshem tawm daim coupon corrosion (yog tias ua tau) thiab kuaj hauv cov txheej txheem dej
Piv txwv tias tus nqi corrosion ntawm 0.2-0.3 hli / xyoo rau kev pabcuam HCl nruab nrab
Yog tias qhov seem phab ntsa thickness tsawg dua qhov tsawg kawg nkaus uas yuav tsum tau muaj rau lub siab ntim ntxiv rau 3-6 hli corrosion pub, yuav tsum tau npaj hloov.
Sib piv nrog cov niaj hnub alloys:Rau cov khoom siv tshiab, B-3 phaj muaj qhov zoo tib yam (lossis zoo dua me ntsis) corrosion kuj hauv kev txo cov kua qaub, zoo dua thermal stability, thiab yooj yim weldability. Tus nqi sib txawv ntawm B thiab B-3 yog qhov tsis txaus ntseeg vim qhov kev txuag nyiaj txiag. Yog li ntawd, thawj Hastelloy B yogyeej tsis tau teev tseg rau tej yaam num tshiab.
Q5: Dab tsi cov qauv thiab cov kev xeem yuav tsum tau siv rau cov cuab yeej cuab tam Hastelloy B phaj, thiab nws yuav tsum tau ntsuas li cas rau kev pabcuam txuas ntxiv?
A:Txij li thawj Hastelloy B phaj tsis tau tsim, tsis muaj cov qauv ASTM rau kev tsim khoom tshiab. Txawm li cas los xij, cov khoom qub tseem tuaj yeem raug soj ntsuam thiab tsim nyog rau kev pabcuam txuas ntxiv siv cov qauv keeb kwm thiab cov qauv kev sim niaj hnub no:
Keeb kwm Standards (rau siv):
ASTM B333 (ua ntej 1985 hloov kho)- Thawj qhov tshwj xeeb rau nickel-molybdenum alloy phaj (nrog rau Hastelloy B raws li Qib N10001)
ASME SB-333 (kev kho ua ntej)- ASME code version
TIAB SA 5549- Aerospace cov khoom specification rau Hastelloy B daim ntawv thiab phaj (tso tseg)
Kev Ntsuam Xyuas Kev Tshawb Fawb Txuas Ntxiv ntawm Txoj Cai B Plate:
Kev txheeb xyuas cov khoom zoo (PMI)- XRF phom kuaj kom paub meej tias cov hlau yog qhov tseeb Hastelloy B (Ni Ntau dua lossis sib npaug 60%, Mo 26-30%, Fe 4-6%, Cr Tsawg dua lossis sib npaug li 1%). Qhov no txawv ntawm B-2 (Fe Tsawg dua lossis sib npaug rau 2%) thiab B-3 (Fe 1.5-3%).
Kev tshuaj ntsuam xyuas tshuaj (ASTM E1473)- Kev soj ntsuam tag nrho los txiav txim siab muaj pes tsawg leeg, tshwj xeeb tshaj yog carbon, silicon, thiab cov ntsiab lus hlau. Qhov no pab kwv yees susceptibility rau intermetallic thiab carbide nag lossis daus.
Kev ntsuas tensile (raws li ASTM E8 / E8M)- Tshem tawm tus qauv tus neeg sawv cev (yog tias ua tau) los ntsuas lub zog tam sim no, lub zog tensile, thiab elongation. Elongation qis dua 20% (piv rau 30% rau B tshiab) qhia tias embrittlement.
Kev sim hardness – Rockwell B or Vickers hardness across the plate thickness. Values >100 HRB (>220 HV) qhia tias nag lossis daus intermetallic. Rau cov cuab yeej cuab tam B phaj, hardness feem ntau txawv ntawm qhov chaw mus rau nruab nrab phab ntsa vim kev laus.
Intergranular corrosion test (ASTM G28 Txoj Kev A) – The most important test for legacy B plate. A sample is exposed to ferric sulfate‑sulfuric acid for 120 hours. Corrosion rate >12 hli / xyoo los yog pom intergranular nres qhia sensitization (carbides los yog intermetallic theem). Yog tias cov qauv ua tsis tiav, lub phaj tsis haum rau kev pabcuam HCl txuas ntxiv.
Kev ntsuam xyuas metallographic- Ntawm 500-1000 × magnification, tshuaj xyuas rau:
Intermetallic theem (Ni₄Mo, Ni₃Mo) - tshwm raws li blocky precipitates ntawm grain ciam teb
Carbides (M₆C, M₂₃C₆) - finer precipitates ntawm grain ciam teb
Cov qoob loo loj (ASTM 3-5 yog qhov zoo rau thawj B)
Ultrasonic thickness kuaj (UT)- Daim ntawv qhia thaj tsam tag nrho los ntsuas qhov seem ntawm phab ntsa thiab kuaj pom cov voids, laminations, lossis cais.
Liquid penetrant testing (PT)- Tshawb xyuas txhua qhov welds thiab qhov chaw muaj kev ntxhov siab rau cov kab nrib pleb.
Kev lees paub rau kev pabcuam txuas ntxiv:
| Parameter | Txais tau | Ceev faj (monitor) | Tsis lees paub (replace) |
|---|---|---|---|
| Elongation | Ntau dua lossis sib npaug li 25% | 15–25% | <15% |
| Hardness (HRB) | Tsawg dua los yog sib npaug li 95 | 95–100 | >100 |
| G28 corrosion tus nqi | Tsawg dua lossis sib npaug li 10 mm / xyoo | 10-15 hli / xyoo | >15mm / xyoo |
| Intergranular nres | Tsis muaj | Yooj yim (dhau) | Sib sib zog nqus los yog txuas ntxiv |
| Cov phab ntsa tuab | Ntau tshaj los yog sib npaug rau min. xav tau + 3mm | Ntau tshaj los yog sib npaug rau min. xav tau |
Cov lus pom zoo rau cov cuab yeej cuab tam B phaj:
Yog tias txhua qhov kev xeem dhau (tseem tau)- Txuas ntxiv kev pabcuam nrog kev tshuaj xyuas txhua xyoo (UT, PT ntawm welds). Saib xyuas cov txheej txheem rau oxidizing cov kab mob.
Yog hais tias ib qho parameter nyob rau hauv qhov kev ceeb toom ntau- Txo cov kev pabcuam kub / siab, nce kev tshuaj xyuas ntau zaus rau peb lub hlis twg, thiab npaj hloov pauv hauv 2-3 xyoos.
Yog tias ib qho parameter nyob hauv qhov tsis lees paub ntau yam- Tshem tawm tam sim ntawm kev pabcuam lossis cais tawm. Hloov nrog B-3 phaj yog tib txoj kev nyab xeeb.
Lus ceeb toom:Tsis muaj lub koob npe nrov fabricator yuav ua kev kho loj lossis hloov kho ntawm cov qub qub Hastelloy B phaj vim muaj kev pheej hmoo ntawm kev tawg. Yog tias cov cuab yeej xav tau kev kho tseem ceeb, kev hloov pauv tsuas yog kev ua kom zoo xwb. Rau tej yaam num tshiab,Hastelloy B-3 phaj(raws li ASTM B333) yuav tsum tau teev - nws muaj superior thermal stability, zoo weldability, thiab zoo tib yam corrosion kuj nyob rau hauv txo acids, ntawm tus nqi ntawm cov khoom sib piv.
