1: Dab tsi yog qhov tseem ceeb ntawm metallurgical sib txawv ntawm ASTM B160 Nickel 200 thiab Nickel 201, thiab vim li cas qhov no ua rau Nickel 201 qib nyiam rau siab -kub fastener thiab cov qauv siv?
ASTM B160 yog tus qauv specification rau nickel pas nrig thiab bar, npog ob qho tib si Nickel 200 (UNS N02200) thiab Nickel 201 (UNS N02201). Lawv qhov sib txawv tseem ceeb yog cov ntsiab lus carbon, qhov tshwj xeeb ntawm qhov tseem ceeb ntawm engineering. Nickel 200 muaj cov ntsiab lus siab tshaj plaws ntawm 0.15 wt%, thaum Nickel 201 yog qhov qis -carbon version, nrog rau qhov siab tshaj plaws ntawm 0.02 wt%.
Qhov sib txawv no dictates lawv daim ntawv thov npe. Ntawm qhov kub siab (feem ntau siab dua 315℃/ 600℃F), cov pa roj carbon nyob rau hauv cov kua dej hauv cov nickel matrix ua txawb. Hauv Nickel 200, cov pa roj carbon no tuaj yeem txav mus rau cov ciam teb thiab nag lossis daus li graphite nodules. Cov txheej txheem no, hu ua graphitization, yog ib qho tseem ceeb tsis ua hauj lwm mechanism:
Nws ua rau embrittlement los ntawm kev tsim voids thiab kev ntxhov siab concentrators ntawm grain ciam teb.
Nws degrades mechanical zog, txo ductility thiab cuam tshuam lub zog.
Nws tuaj yeem ua rau intergranular corrosion raws li cov graphite muab txoj hauv kev rau corrosive agents.
Nickel 201's ultra- cov ntsiab lus qis carbon tseem ceeb tshem tawm qhov kev pheej hmoo no. Yog li ntawd, rau cov kab puag ncig uas yuav tsum tau muab tso rau hauv cov khoom xws li siab - kub bolts, studs, valve stems, springs, thiab furnace fixtures uas ua hauj lwm tsis tu ncua los yog cyclically nyob rau hauv lub 315℃mus rau 650℃(600℃F txog 1200℃F), Nickel 201 yog qhov yuav tsum tau xaiv. ASTM B160 muab cov khoom siv tshuaj lom neeg thiab cov khoom siv kho tshuab kom ntseeg tau tias cov khoom siv muaj cov khoom siv thermal stability.
2: Nyob rau hauv qhov tshwj xeeb corrosive kev pab cuam ib puag ncig yog Nickel 201 round bars indispensable, thiab dab tsi lub zog tso cai rau lawv ua tau zoo tshaj stainless hlau thiab lwm yam nickel alloys?
ASTM B160 Nickel 201 round bars yog cov khoom ntawm kev xaiv rau kev siv qhov twg ob qho tib si corrosion hnyav thiab siab - kub muaj peev xwm converge. Lawv lub niche yog txhais los ntawm kev ua tau zoo tshaj plaws hauv kev tawm tsam tshwj xeeb.
Qhov Chaw Pabcuam Tseem Ceeb:
Kub, Concentrated Caustic (NaOH / KOH) Kev daws teeb meem: Nickel 201 nthuav tawm qhov ua tau zoo rau alkalis thoob plaws txhua qhov siab thiab kub mus txog thiab dhau qhov melting point ntawm caustic. Qhov no ua rau nws zoo tagnrho rau bar Tshuag siv nyob rau hauv evaporator shafts, agitators, thiab fastener systems nyob rau hauv caustic ntau lawm thiab tuav cov khoom, qhov twg stainless steels yuav raug kev txom nyem los ntawm kev nyuaj siab corrosion cracking thiab active corrosion.
Halogen (Fluorine, Chlorine, Bromine) thiab Qhuav Hydrogen Halide Ib puag ncig: Hauv cov dej tsis muaj dej los yog qis- cov dej noo, Nickel 201 tsim cov tshuaj fluoride lossis chloride scale. Nws tau teev tseg rau valve stems, twj rods, thiab instrumentation Cheebtsam nyob rau hauv fluorine thiab chlorine tshuaj ua.
Siab -Qhov Kub Txo Cov Cuab Yeej: Hauv cov txheej txheem cuam tshuam nrog hydrogen, tawg ammonia, lossis carbon monoxide ntawm qhov kub thiab txias, Nickel 201 tuav nws lub zog thiab tsis raug kev puas tsuaj los ntawm kev puas tsuaj oxidation lossis embrittlement li ntau cov hlau -raws li alloys ua. Nws yog siv rau radiant tube hangers, thermocouple sheaths, thiab retort Cheebtsam.
Khoom noj khoom haus thiab tshuaj ua: Nws zoo heev corrosion kuj, ua ke nrog uas tsis yog - paug cov khoom thiab yooj yim ntawm tu, ua rau nws haum rau machined qhov chaw nyob rau hauv cov khoom tseem ceeb, tshwj xeeb tshaj yog thaum polished.
Comparative zoo:
vs. Stainless Steels (xws li, 316, 317): Nickel 201 tiv thaiv chloride-induced stress corrosion cracking (SCC) thiab muaj kev tiv thaiv zoo heev rau kub, tsis yog -oxidizing acids thiab alkalis. Nws lub hnab ntawv kev ua tau zoo txuas mus rau qhov kub thiab txias ntau yam tsis muaj kev poob ntawm ductility.
vs. Nickel-Copper Alloys (Alloy 400/K-500): Thaum Alloy 400 zoo tshaj nyob rau hauv hydrofluoric acid thiab seawater, Nickel 201 muaj zoo dua kub-kub zog, oxidation kuj, thiab thermal stability.
vs. Higher Nickel Alloys (C-}276, 625): Rau cov cheeb tsam tshwj xeeb uas tau teev tseg saum toj no, Nickel 201 muab cov khoom txaus txaus-thiab feem ntau tshwj xeeb- corrosion kuj ntawm tus nqi qis dua. Nws yog qhov kev daws teeb meem zoo tshaj plaws, tus nqi tsim nyog qhov twg nws cov cuab yeej tshwj xeeb tau teeb tsa raws li qhov yuav tsum tau ua.
3: Dab tsi yog qhov tseem ceeb ntawm cov cuab yeej cuab tam thiab cov kev tso cai (tempers) rau Nickel 201 puag ncig tuav hauv qab ASTM B160, thiab lawv cuam tshuam rau kev ua haujlwm thiab xaus li cas - siv kev ua haujlwm?
ASTM B160 txhais tsis tau tsuas yog chemistry tab sis kuj tseem ceeb cov khoom siv kho tshuab thiab cov txheej txheem tempers uas txuas kev tsim khoom rau daim ntawv thov.
Cov Ntsiab Lus Mechanical Requirements (Ib yam rau Annealed Condition):
Tensile zog: Yam tsawg kawg nkaus 380 MPa (55 ksi)
Yield zog (0.2% Offset): Tsawg kawg 105 MPa (15 ksi)
Elongation: Yam tsawg kawg 40% hauv 2 nti (50 mm)
Cov khoom no qhia txog cov yam ntxwv ntawm kev sib xyaw ua ke ntawm lub zog nruab nrab thiab qhov tshwj xeeb ductility hauv nws lub xeev annealed, vim nws lub ntsej muag -centered cubic (FCC) qauv thiab siab purity.
Standardized Tempers & Lawv cuam tshuam:
ASTM B160 tso cai rau cov khoom siv hauv ntau yam xwm txheej, txhua qhov tsim nyog rau kev ua haujlwm tom ntej:
Kub tiav: Raws li -extruded los yog kub- dov. Nws muaj qhov scaled nto thiab feem ntau yog qhov softest mob, haum rau hnyav machining qhov twg deg tag tsis tseem ceeb.
Annealed (Qhov Kev Pabcuam Feem Ntau): Ua kom sov rau qhov kub siab tshaj nws qhov chaw recrystallization (feem ntau 705-925℃/ 1300-1700℃F) thiab txias. Qhov no ua rau cov qauv zoo sib xws, equiaxed grain qauv nrog siab tshaj plaws ductility thiab softness, zoo tagnrho rau complex machining, txias forming (xws li xov dov), thiab muab ib tug zoo xws li cov hauv paus ntsiab lus rau tej zaum kawg kev kho cua sov los ntawm cov neeg siv kawg.
Cold Drawn / Cold Finished: Lub bar yog kos los ntawm kev tuag ntawm chav tsev kub. Qhov no ua rau muaj zog tensile thiab yield zog (xws li, yield zog tuaj yeem tshaj 550 MPa / 80 ksi) los ntawm kev ua hauj lwm hardening thaum txhim kho nto tiav thiab qhov ntev kam rau ua. Nws tau teev tseg rau cov khoom uas xav tau lub zog siab dua yam tsis muaj kev kho cua sov thiab qhov twg yuav tsum tau ua kom tiav qhov zoo. Txawm li cas los xij, nws nyuaj rau lub tshuab thiab tej zaum yuav xav tau kev ntxhov siab ua ntej siv kom tsis txhob muaj kev cuam tshuam.
Kev cuam tshuam ntawm Kev Ua Haujlwm: Kev xaiv kev npau taws yog qhov tseem ceeb. Ib qho annealed bar yog zoo meej rau lub complex machined valve lub cev. Lub tshuab nqus dej txias tuaj yeem raug xaiv rau lub twj tso kua mis ncaj nraim uas xav tau siab dua li - muab lub zog thiab ua kom tiav. Tus txheej txheem ua kom ntseeg tau tias tsis hais tus neeg xa khoom, lub bar tau xaj rau "ASTM B160, UNS N02201, Annealed" yuav muaj cov khoom pov thawj, muaj pov thawj rau engineering tsim thiab fabrication.
4: Dab tsi yog qhov tseem ceeb machining thiab fabrication txiav txim siab rau kev ua hauj lwm nrog ASTM B160 Nickel 201 round bar, muab nws cov hauj lwm -hardening nyiam?
Thaum Nickel 201 feem ntau suav hais tias yog machinable ntau dua li ntau cov austenitic stainless hlau, nws cov lus tshaj tawm ua haujlwm - cov yam ntxwv tawv tawv xav tau cov txheej txheem tshwj xeeb kom ua tiav lub neej zoo thiab qhov tseeb ntawm qhov ntev.
Cov kev sib tw tseem ceeb thiab cov kev coj ua zoo tshaj plaws:
Kev Sib Tw: Kev Ua Haujlwm nrawm nrawm. Qhov saum npoo tam sim ntawd nyob rau hauv lub cuab yeej txiav tuaj yeem ua rau muaj zog heev, ua rau muaj zog txiav ntau dua, cov cuab yeej hnav, thiab muaj peev xwm ua kom tsis zoo ntawm qhov chaw ua haujlwm.
Mitigation Strategy:
Cov cuab yeej Geometry & Khoom siv: Siv cov ntse ntse, zoo-rake txiav cov cuab yeej ua los ntawm cov qib hwm ntawm carbide (piv txwv li, C-2 lossis C-3 qib) lossis high-speed steel (HSS) nrog txheej (TiN, AlTiN). Cov cuab yeej yuav tsum ceev ceev; ib tug dull cuab yeej exacerbates ua hauj lwm hardening.
Txiav tsis: Siv qis- mus rau- nruab nrab txiav nrawm nrog qhov sib xws, nruab nrab- mus rau - hnyav pub nqi. Lub teeb pub los yog "lub tsev" nrog lub cuab yeej ua rau muaj kev puas tsuaj vim nws rub thiab ua haujlwm- ua kom tawv tawv tsis txhob txiav nws. Lub hom phiaj yog txiav hauv qab qhov chaw ua haujlwm - txheej tawv tawv los ntawm kev dhau dhau los.
Coolant: Siv lub tshuab ua kom muaj zog thiab siab tshaj -cov dej txias kom ua kom cov cua sov ntawm qhov sib cuam tshuam, txo kev ua haujlwm nyuaj, thiab txhim kho nti khiav tawm.
Kev sib tw: Stringy, tawv chips. Nickel alloys zoo li tsim cov chips ntev, tsis tu ncua uas tuaj yeem tangle thiab ua rau muaj kev nyab xeeb.
Kev txo qis: Siv cov nti- rhuav tshem cov cuab yeej geometry. Hauv kev ua haujlwm CNC, siv qhov programmed pecking cycles rau drilling thiab cov nti tshwj xeeb -txhua txoj haujlwm.
Fabrication Notes:
Vuam: Nickel 201 muaj qhov zoo tshaj plaws weldability. Siv Gas Tungsten Arc Vuam (GTAW/TIG) nrog cov muab tub lim ERNi-1. Kev tu kom zoo kom tshem tawm cov oxides thiab cov kab mob (sulfur, lead, phosphorus) yog qhov tseem ceeb los tiv thaiv kev tawg.
Forging / Kub Ua Haujlwm: Qhov pom zoo kub - ua haujlwm ntau yog 650℃txog 1230℃(1200℃F txog 2250℃F). Nws yuav tsum tsis txhob forged hauv qab 650 degree.
5: Yuav ua li cas cov nqi ntawm lub neej thiab kev ntseeg siab tsom xam ua pov thawj cov ntsiab lus ntawm Nickel 201 round bar dua pheej yig dua, qis dua - cov ntaub ntawv ua tau zoo hauv cov tshuab tseem ceeb?
Kev qhia txog ASTM B160 Nickel 201 yog ib qho kev tawm dag zog hauv tag nrho cov nqi engineering, qhov twg tus nqi pib ntawm cov khoom siv ntau dua yog tsim nyog los ntawm kev lag luam kev lag luam zoo tshaj plaws thiab kev txo qis.
Kev Pabcuam Sijhawm Ntxiv thiab Txo Kev Kho Mob: Hauv qhov kub kub evaporator, stainless hlau ncej yuav corrode, tawg, los yog warp nyob rau hauv ob peb xyoos, yuav tsum tau ib tug kim kaw rau hloov. Lub Nickel 201 ncej tuaj yeem nyob rau ntau xyoo hauv tib qhov kev pabcuam, tshem tawm ntau lub voj voog hloov, cuam tshuam cov nqi zog, thiab kev tsim khoom poob qis. Qhov kev ntseeg tau ncaj qha txhais mus rau cov nroj tsuag muaj ntau dua thiab dhau los.
Kev tiv thaiv kev puas tsuaj loj: Qhov tshwm sim ntawm lub fastener (bolt / stud) tsis ua hauj lwm nyob rau hauv ib tug siab - kub, siab - siab reactor los yog ib tug turbine casing tsis yog ib qho kev hloov khoom. Nws tuaj yeem ua rau muaj kev puas tsuaj uas tsis tau npaj tseg, cov cuab yeej siv loj puas tsuaj, teeb meem kev nyab xeeb, thiab kev tso tawm ib puag ncig. Nickel 201's proven resistance to thermal embrittlement (graphitization) thiab corrosion ua kom lub sij hawm ntev -kev ncaj ncees ntawm cov kev sib txuas tseem ceeb no, muab kev pov hwm txoj cai tiv thaiv kev puas tsuaj loj.
Kev Ua Haujlwm Yooj Yim thiab Kev Nyab Xeeb Kev Nyab Xeeb: Cov txheej txheem ua nrog Nickel 201 Cheebtsam muaj lub hnab ntawv ua haujlwm zoo dua. Lawv muaj peev xwm zam tau qee qhov kev ntxhov siab, kev mus ncig ua si, lossis kev hloov pauv hauv cov khoom noj khoom haus uas yuav cuam tshuam cov ntaub ntawv tsawg dua. Qhov no ua tau - nyob rau hauv kev nyab xeeb margin txo cov kev pheej hmoo ua hauj lwm thiab muab kev yooj yim tsim.
Tus nqi ntawm Downtime vs. Material Premium: Hauv kev lag luam txuas ntxiv (tshwj xeeb, petrochemicals, tshuaj), cov nqi poob qis tuaj yeem tshaj li pua pua txhiab nyiaj hauv ib hnub. Tus nqi nce ntxiv ntawm kev siv Nickel 201 bar Tshuag tshaj cov pa roj carbon lossis stainless hlau feem ntau yog ib feem me me ntawm tus nqi ntawm ib qho kev poob qis. Kev nqis peev yog nyob rau hauv kev kwv yees, kev ua haujlwm tsis cuam tshuam.
Yog li ntawd, qhov tshwj xeeb ntawm ASTM B160 Nickel 201 yog qhov ncaj ncees tsis yog los ntawm nws thawj tus nqi, tab sis los ntawm nws tus nqi qis tshaj plaws hauv lub neej. Nws yog qhov kev xaiv tsim nyog rau cov kws tsim qauv tsim cov tshuab uas muaj kev ntseeg siab, kev nyab xeeb, thiab ntev - cov nqi khiav lag luam yog qhov kev txhawj xeeb tseem ceeb.
