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QUICK teb
Rau cov ntshiab oxidizing (cua) cua mus txog kwv yees li 2,000℃F (1,093 degree) uas tsis muaj kev txhawb nqa txhua yam, 310S stainless hlau (UNS S31008, ASTM A240) yog qhov kev xaiv pheej yig dua.
Rau carburizing, sulfidizing, lossis load- kev pabcuam kabmob - radiant tubes, ethylene cracking coils, kiln rollers, siab- khaws cov khoom siv rau hauv cub tawg - Incoloy 800H/800HT (UNS N08810/N088107, ASTs B. creep- tawg lub zog thiab carburization tsis kam thiab tsim nyog nws tus nqi hwm.
310S yog nquag mus rau sigma-theem embrittlement ntawm kwv yees li 1,200℃F thiab 1,650℃F (650–900 degree) tom qab lub sijhawm ntev; Incoloy 800H / HT feem ntau zam qhov kev ua tsis tiav no. |
Taw qhia
Rauv, kiln, thiab thermal- cov engineers ua haujlwm niaj hnub ntsib cov khoom siv tib yam kev txiav txim siab: qhia tus nqi-cov cua sov zoo-cov hlau tsis muaj zog, lossis nce mus rau npib tsib xee- hlau- chromium alloy ua rau muaj zog siab - qhov kub thiab txias.310S stainless hlauthiab Incoloy 800 (xws li 800H thiab 800HT variants) yog ob feem ntau sib piv cov neeg sib tw rau qhov kev txiav txim siab no. Ob leeg tiv thaiv oxidation ntawm qhov kub thiab txias, ob qho tib si tau yooj yim fabricated thiab welded, thiab ob qho tib si tshwm nyob rau hauv lub qhov rooj rauv, muffles, radiant tubes, thiab cua sov- kho fixtures.
Lawv qhov kev ua tau zoo sib txawv heev, txawm li cas los xij, ib zaug carburizing cua, cov khoom siv hluav taws xob ruaj khov, lossis cov kev pabcuam ntev nkag mus rau hauv daim duab. Kab lus no muab ob qho kev sib piv ntawm ob qho kev sib xyaw ua ke, qhov muaj peev xwm kub, oxidation thiab carburization tsis kam, creep- tawg lub zog, fabrication yuav tsum, thiab tag nrho cov nqi ntawm cov tswv, kom engineers thiab buyers tuaj yeem phim cov alloy rau daim ntawv thov ntau dua li lwm txoj hauv kev.
Dab tsi Distinguishes 310S los ntawm Incoloy 800 Metallurgically?
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310S yog siab -chromium austenitic stainless hlau (Fe-Cr-Ni, roughly 25% Cr / 20% Ni) engineered rau nqi-zoo oxidation kuj.Incoloy 800/800H/800HTyog npib tsib xee- hlau-chromium alloy (kwv yees li 32% Ni / 21% Cr, hlau tshuav) ua haujlwm feem ntau rau siab - kub lub zog thiab carburization tsis kam, ntawm tus nqi ntau dua nickel. |
Qhov sib txawv muaj pes tsawg leeg yog lub hauv paus ua rau txhua qhov kev sib txawv ntawm cov dej ntws sib txawv uas tau tham hauv tsab xov xwm no . 310S nqa chromium ua nws cov ntsiab lus alloying thiab npib tsib xee ua cov austenite stabilizer thib ob, uas yog vim li cas nws tau muab cais ua cov hlau tsis zoo es tsis yog npib tsib xee alloy. Incoloy 800 inverts qhov piv: npib tsib xee yog feem ntau alloying ntxiv, chromium yog theem nrab, thiab hlau ua kom qhov sib npaug es tsis yog lub hauv paus hlau. Cov ntsiab lus npib tsib xee ntau dua yog qhov muab 800-series alloys lawv tsis kam rau cov pa roj carbon diffusion thiab lawv lub zog khaws cia ntawm qhov kub thiab txias - tab sis npib tsib xee kuj yog cov khoom siv raw khoom kim dua, uas yog vim li cas Incoloy 800 series cov khoom lag luam nqa tus nqi pheej yig dua 310S.
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Lub ntsiab |
310S (UNS S31008, ASTM A240) |
Incoloy 800H (UNS N08810, ASTM B407 / B409) |
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Nickel (Ni) |
19.0 – 22.0% |
30.0 – 35.0% |
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Chromium (Cr) |
24.0 – 26.0% |
19.0 – 23.0% |
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Hlau (Fe) |
Tshuav |
Qhov nyiaj tshuav (39.5% min) |
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Cov pa roj carbon (C) |
0.08% max |
0.05 – 0.10% |
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Aluminium + Titanium |
Tsis tau teev tseg |
0.85 - 1.20% (0.30 - 1.20% txhua) |
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Manganese (Mn) |
2.0% max |
1.5% max |
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Silicon (Si) |
1.5% max |
1.0% max |
Tau qhov twg los: ASTM A240 / A480 (310S); ASTM B407 / B408 / B409 thiab UNS N08810 zeb specifications (Incoloy 800H). Ranges yog nominal specification txwv; txheeb xyuas daim ntawv qhia txog kev xeem mills tam sim no.
Ob qho ntxiv cov ntsiab lus tseem ceeb rau kev pabcuam rau lub cub tawg. Ua ntej, 310S yog qhov tsawg- carbon variant ntawm tus qauv qib 310 (uas tso cai rau 0.25% carbon); Cov pa roj carbon qis hauv 310S txhim kho kev tiv thaiv rau kev hnov qab thiab intergranular corrosion tom qab vuam. Thib ob, Incoloy 800H yog nws tus kheej tswj tau -carbon, tswj- nplej- qhov txawv ntawm lub hauv paus Incoloy 800, thiab Incoloy 800HT ntxiv zawm cov txhuas-ntxiv rau-titanium ntau yam - ob qho tib si rau kev kho kom zoo nkauj muaj zog thiab txheej txheem-cov kev pabcuam cua sov, uas tau tham hauv Tshooj 4.
Yam Alloy Withstands siab dua kev khiav hauj lwm kub?
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Ob lub alloys raug ntsuas rau kev pabcuam txuas mus ntxiv hauv 2,000℃F (1,093 degree), tab sis lawv tau txais qhov sib txawv: 310S raug txwv tsuas yog los ntawm oxidation thiab los ntawm sigma-theem embrittlement nyob rau hauv 1,200-1,650℃F band, thaum Incoloy poob 800H yog txwv rau qhov kub thiab txias li ntawm 800H / H. 2,000℃F. |
310S feem ntau yog ntsuas rau kev tiv thaiv oxidation tsis tu ncua txog li 2,000℃F (1,093 degree) thiab rau kev sib cuam tshuam lossis kev pabcuam me me rau qhov zoo sib xws, vim nws cov ntsiab lus chromium siab. Lub tswv yim limiter rau 310S nyob rau hauv cub tawg thiab kiln kev pab cuam tsis yog oxide nplai - nws yog sigma- theem tsim. Tom qab ncua ntev ntawm qhov kub ntawm 1,200℃F thiab 1,650℃F (650-900 degree), 310-tsev neeg stainless hlau tuaj yeem tsim cov nkig intermetallic sigma theem uas txo cov chav kub thiab ductility. Cov cuab yeej siv los ntawm qhov ntsuas kub no ntau zaus, xws li lub qhov rooj rau qhov cub thiab cov khoom siv hluav taws xob, yog qhov cuam tshuam ntau dua li cov khoom siv uas ua haujlwm tsis tu ncua ntawm qhov kub thiab txias.
Incoloy 800 Hthiab 800HT raug ntsuas rau lub sijhawm ntev- kev pabcuam mus txog kwv yees li 2,000℃F (1,093 degree), nrog luv luv -ntev excursions ua tau saum toj no ntawm tus nqi ntawm kev ua kom lub zog poob thiab oxidation. Vim hais tias 800-series alloys yog cov tshuaj{14}}annealed ntawm qhov tsawg kawg nkaus ntawm 2,100℃F (1,149 degree) los tsim ib coarser, creep ntau dua-cov qauv grain tiv taus, thiab vim tias lawv cov ntsiab lus ntau dua nickel suppresses tib sigma-theem txheej txheem uas cuam tshuam rau 310S kev sib txuas ntawm peb qhov kev sib tw, thiab lawv cov khoom siv tau zoo heev. qhov cub ua haujlwm ntau yam, suav nrog kev rov ua dua thermal cycling.
Dab tsi Alloy muaj kev tiv thaiv zoo dua rau Oxidizing thiab Carburizing Atmospheres?
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Rau kev huv, oxidizing (cua) cua, 310S ua tau zoo heev thiab yog qhov kev xaiv pheej yig dua. Rau carburizing, txo, los yog sulfur- bearing atmospheres - muaj nyob rau hauv tshav kub- kho furnaces, ethylene cracking, thiab hydrocarbon ua - Incoloy 800H / HT yog qhov kev xaiv muaj zog vim nws cov ntsiab lus nickel siab dua txwv cov pa roj carbon solubility thiab diffusion rau hauv cov hlau. |
Oxidation kuj nyob rau hauv ob qho tib si alloys feem ntau yog los ntawm chromium, uas tsim ib tug tiv thaiv chromium - oxide nplai ntawm qhov kub thiab txias . 310S tiag tiag nqa chromium ntau dua Incoloy 800H (kwv yees 25% piv rau roughly 21%), uas yog ib qho laj thawj 310S tseem muaj zog, kev lag luam hauv huab cua zoo li cov khoom siv hluav taws xob zoo. thiab burner hardware.
Carburization kuj yog ib qho kev sib txawv, thiab qhov no yog qhov uas ob lub alloys diverge feem ntau sharply. Cov pa roj carbon hloov mus rau hauv cov hlau nto los ntawm cov pa roj carbon - huab cua nplua nuj nyob ntawm cov ntsiab lus npib tsib xee, vim tias nickel muaj cov solubility tsawg heev rau cov pa roj carbon monoxide thiab slows nws inward diffusion. Cov ntaub ntawv pov thawj ntawm 800H tubing hauv carburizing hydrocarbon- kev pabcuam ua haujlwm qhia tau hais tias cov hlau tuav cov ductility thiab kev ncaj ncees ntawm cov qauv tom qab tau raug ntau xyoo, nyob rau hauv cov xwm txheej uas qis dua -nickel 310- tsev neeg stainless hlau carburize ntsuas sai dua. Qhov no yog qhov laj thawj tseem ceeb ntawm Incoloy 800H yog cov khoom siv tseem ceeb rau ethylene pyrolysis hlab, hydrocarbon cracking furnace Cheebtsam, thiab cov pob tawb kho cua sov thiab cov khoom siv uas pom rov ua dua carburizing.
Tshaj tawm corrosion- tus nqi sib piv nyob rau hauv refinery furnace ib puag ncig qhia qhov sib txawv: Incoloy 800H / 800HT alloys tau ntsuas ntawm kwv yees li 0.15 mm / xyoo (6.0 mpy), piv rau kwv yees li 0.23 mm / xyoo (8.9 mpy) rau 310-tsev neeg stainless hlau hauv qab. Tus nqi qis dua txhais tau ncaj qha mus rau hauv lub neej ntev dua thiab tsis muaj kev npaj tsis txaus rau kev tshuaj xyuas lossis hloov.
Creep thiab Stress li cas -Rupture Strength Sib piv ntawm qhov kub siab?
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Incoloy 800H thiab 800HT xa cov creep ntau dua - tawg lub zog ntau dua 310S ntawm qhov kub thiab txias, uas yog vim li cas lawv yog qhov kev qhia tshwj xeeb rau siab-cov kabmob lossis thauj khoom-cov kabmob rau cov khoom siv hluav taws xob - radiant tubes, headers,}10 roughly 18 (18 F) degree). |
Creep yog qhov qeeb, lub sij hawm- nyob ntawm qhov deformation ntawm cov hlau nyob rau hauv kev ruaj khov ntawm qhov kub thiab txias, thiab kev ntxhov siab- tawg lub zog piav qhia tias muaj kev ntxhov siab npaum li cas cov khoom tuaj yeem nqa tau ua ntej nws tawg tom qab lub sijhawm ua haujlwm. Cov cuab yeej no tseem ceeb rau txhua qhov cub hluav taws xob uas tsis muaj load thaum kub - lub raj radiant nyob rau hauv lub siab sab hauv, lub hanger txhawb refractory, los yog ib tug coil nyob rau hauv ib tug pyrolysis rauv - raws li txawv los ntawm cov khoom uas tsuas yog raug tshav kub uas tsis muaj ib tug tseem ceeb mechanical load, xws li ib tug muffle liner los yog ntaub thaiv npog.
310S muaj kev nkag siab nruab nrab- tawg lub zog, txaus rau cov khoom siv me me. Incoloy 800H thiab 800HT tau tsim tshwj xeeb los ua kom ntev creep- tawg lub neej tshaj li tus qauv 800 lossis 310- tsev neeg stainless hlau muab, los ntawm cov ntsiab lus ntawm cov pa roj carbon monoxide (0.05–0.10%) thiab ntxhib- cov nplej kua tshuaj anneal ntawm qhov tsawg kawg nkaus ntawm 10 14 F (1, 19 ° F). Incoloy 800HT nruj aluminium-thiab-titanium specification ntxiv rau saum toj no, rau cov ntawv thov uas xav tau lub neej ua haujlwm ntev tshaj plaws nyob rau hauv kev kub ntxhov siab, xws li ethylene furnace tubing thiab pyrolysis coils.
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Khoom |
310S |
Incoloy 800H / 800HT |
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Kev pabcuam kub tsis tu ncua |
Mus txog ~ 2,000℃F (1,093 degree) |
Mus txog ~ 2,000℃F (1,093 degree), ntev -lub sij hawm |
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Creep- tawg zog |
Nruab nrab |
Siab (tsim qauv tsim ntawm 800H / HT) |
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Sigma-phase embrittlement risk |
Yog, 1,200–1,650℃F (650–900 degree) |
Tsawg heev, vim Ni cov ntsiab lus siab dua |
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Carburization kuj |
Ncaj ncees |
Zoo rau zoo heev |
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Corrosion tus nqi, refinery rauv lub luag hauj lwm |
~ 0.23 hli / xyoo (8.9 mpy) |
~ 0.15 hli / xyoo (6.0 mpy) |
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Chav - qhov kub thiab txias yield zog |
~ 30 ksi (ntev annealed) |
30-45 ksi (207-310 MPa) |
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Tus nqi ntawm cov khoom siv txheeb ze |
Lower (lub hauv paus) |
Siab dua, tsav los ntawm Ni cov ntsiab lus |
Tau qhov twg los: Muab tso ua ke los ntawm ASTM A240/B407/B409 specification cov ntaub ntawv thiab luam tawm siab -kub corrosion- tus nqi thiab txhua yam - kev tshawb fawb vaj tse rau 310/310H thiab Incoloy 800H / 800HT nyob rau hauv refinery thiab furnace kev pab cuam. Txheeb xyuas cov qauv tsim tau tso cai tawm tsam tam sim no ASME Tshooj II Ntu D lossis siv tau cov lej luam ua ntej qhov tshwj xeeb kawg.
Tus nqi sib txawv yog dab tsi, thiab Thaum twg Qhov Nyiaj Them Nqi Zoo?
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Incoloy 800 series cov khoom raug nqi ntau dua 310S vim tias nws cov ntsiab lus 30-35% npib tsib xee, kwv yees li 50% siab dua 310S. Tus nqi them yog tsim nyog thaum daim ntawv thov cuam tshuam nrog cov khoom siv hluav taws xob ruaj khov, carburizing lossis sulfidizing huab cua, lossis thaum lub sijhawm poob rau kev hloov pauv yog kim piv rau cov nqi sib txawv. |
Nickel tsis tu ncua yog tus tsav tsheb loj tshaj plaws ntawm cov nqi sib tw rau ob qho khoom siv, tab sis Incoloy 800H / HT nqa kwv yees li 50 feem pua nickel ntau dua los ntawm qhov hnyav dua 310S, thiab npib tsib xee feem ntau ua lag luam ntawm ntau yam ntawm chromium thiab hlau uas ua rau feem ntau ntawm 310S cov ntsiab lus alloy. Qhov no ua rau 800-series alloys yuav kim dua ntawm ib - phaus lossis ib -linear-foot hauv paus, ua ntej fabrication txawm xav txog.
Cov txheej txheem kev txiav txim siab uas ua raws los ntawm kev sib piv cov txheej txheem saum toj no yog ncaj nraim. Qhia meej 310S thaum cov khoom siv pom cov huab cua oxidizing huv, lub teeb lossis tsis muaj cov khoom siv thauj khoom, thiab kev pabcuam nruab nrab- kev cia siab rau lub neej - cub tawg plhaub, qhov rooj, kiv cua, thiab tsis yog -load- cov kabmob shields yog ib txwm haum. Qhia meej Incoloy 800H lossis 800HT thaum cov khoom siv nyob rau hauv qhov ntsuas kub tsis tu ncua, raug rau qhov chaw carburizing lossis sulfidizing, lossis thaum tus nqi ntawm kev kaw tsis tau npaj los hloov cov khoom ua tsis tau zoo tshaj cov khoom siv tus nqi hwm - radiant tubes, txheej txheem -cov khoom siv hluav taws xob, co 1 ethylene thiab fixtures. ntev carburizing cycles yog ib txwm haum.
Fabrication, Vuam, thiab kev kho cua sov sib txawv li cas?
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Ob lub alloys tau yooj yim welded nrog tus qauv austenitic cov tswv yim thiab cov khoom siv hlau sib txuam, tab sis Incoloy 800H / HT yuav tsum muaj ntau dua -kub tshuaj anneal (2,100℃F / 1,149℃yam tsawg kawg nkaus) los teeb tsa cov qauv coarse uas nws lub zog creep nyob ntawm, thaum 310S siv qis dua 1, 109, ntau dua. |
310S yog kev daws teeb meem-annealed nyob rau hauv thaj tsam ntawm 1,900–2,100℃F (1,030–1,150 degree) ua raws li cov cua txias sai, uas tso cov carbides rov qab rau hauv cov tshuaj thiab ua kom muaj zog corrosion. Yog hais tias 310- cov cuab yeej siv hauv tsev neeg tau pom cov kev pabcuam txuas ntxiv siab dua 1,200℃F (650 degree) thiab qib sigma tau tsim, ductility feem ntau tuaj yeem rov qab los nrog tib txoj kev daws teeb meem -anneal voj voog; qhov rov ua dua tom qab kwv yees li txhua 1,000 teev ntawm kev pabcuam siab tshaj 1,200℃F yog qhov feem ntau hais txog kev saib xyuas lub sijhawm rau cov cuab yeej ua rau muaj kev ua sigma.
Incoloy 800H thiab 800HT xav tau cov tshuaj anneal ntawm qhov tsawg kawg nkaus ntawm 2,100℃F (1,149 degree) - noticeably siab dua cov anneal siv rau 310S - tshwj xeeb los tsim ib coarser grain qauv (feem ntau ASTM grain loj No. 5 los yog coarserure{1. Ob lub alloys yog weldable los ntawm standard gas tungsten arc thiab shielded hlau arc txheej txheem nrog txuam los yog nyob ze - txuam muab tub lim hlau, thiab ob qho tib si yog conventionally txias- tsim, tab sis cov 800-series alloys tuaj yeem pom cov yam ntxwv ntawm qhov zoo nkauj ("txiv kab ntxwv tev") tom qab hnyav hnyav vim lawv coarser grain loj.
Dab tsi Alloy Koj Yuav Tsum Qhia rau Cov Cuab Yeej thiab Kiln?
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Siv 310S rau tsis yog- thauj khoom- cov kabmob, huv - cua sov cua sov thiab cov khoom siv hluav taws xob; siv Incoloy 800H / 800HT rau txhua yam nyob rau hauv kev ruaj ntseg load, nyob rau hauv ib tug carburizing los yog sulfidizing huab cua, los yog qhov chaw uas unplanned hloov yog kim heev. |
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Cheebtsam / Ib puag ncig |
Pom zoo Alloy |
Vim li cas |
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Rauv plhaub, qhov rooj, kiv cua, ducting (cua cua) |
310S |
oxidation kuj zoo heev, tus nqi qis tshaj |
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Burner qhov chaw, recuperators, piping (nruab nrab load) |
310S |
Zoo oxidation thiab thermal -cycling resistance |
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Thaum tshav kub kub- kho pob tawb thiab khoom siv (rov ua dua carburizing) |
Incoloy 800 H |
Superior carburization kuj ncua kev pab lub neej |
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Radiant raj, txheej txheem- rhaub tubing (sustained siab) |
Incoloy 800H / 800HT |
Creep- tawg lub zog yuav tsum tau nyob rau hauv tas li load |
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Ethylene pyrolysis / hydrocarbon cracking coils |
Incoloy 800 HT |
Qhov siab tshaj plaws creep zog thiab carburization tsis kam rau kev sib tw ntev ntev |
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Kiln rollers, hangers, kev txhawb nqa ntawm qhov kub thiab txias |
Incoloy 800 H |
Sustained mechanical load nyob rau hauv tshav kub nyiam dua creep zog |
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Cov kua dej- txaj rauv taws, lub thawv cua, cov kav dej |
310S |
Cyclic oxidizing kev pab cuam qhov twg tus nqi efficiency tseem ceeb |
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Tau qhov twg los: Kev taw qhia kev xaiv dav dav raws li cov ntaub ntawv alloy cov khoom thiab cov khoom siv hluav taws xob sib xyaw ua ke / qhov cub ua haujlwm. Cheebtsam -kev xaiv tshwj xeeb yuav tsum suav rau qhov tseeb ntawm huab cua chemistry, kev ntsuas siab, thermal cycling zaus, thiab cov qauv tsim qauv.
Cov lus nug nquag
Q: 310S thiab Incoloy 800H puas tuaj yeem siv sib hloov hauv tib lub cub tawg?
A: Tsis yog feem ntau. Lawv muaj qhov sib txawv ntawm cov thermal expansion thiab cov cwj pwm sib txawv, yog li kev sib xyaw ua ke hauv ib qho welded los ua ke hauv kev thauj khoom tuaj yeem tsim kev ntxhov siab sib txawv. Qhov twg ob qho tib si tshwm sim nyob rau hauv tib lub cub tawg, lawv feem ntau yog siv nyob rau hauv kev sib cais, ntawm nws tus kheej txhawb cov Cheebtsam - piv txwv li, ib tug 310S plhaub nrog Incoloy 800H sab hauv tubing.
Q: Puas yog Incoloy 800 tib yam li Incoloy 800H lossis 800HT?
A: Tsis yog. Standard Incoloy 800 (UNS N08800) tso cai rau cov pa roj carbon ntau thiab tsis nqa cov ntxhib - nplej, siab -kub tshuaj anneal uas muab 800H (UNS N08810) thiab 800HT (UNS N08811) 800 lawv lub zog zoo dua Hauv qhov cub hluav taws xob tam sim no thiab cov txheej txheem-cov ntsuas cua sov, 800H thiab 800HT tau hloov pauv tus qauv 800.
Q: Puas yog 310S xav tau kev tshaj tawm -weld kev kho cua sov?
A: Tsis yog rau corrosion kuj nyob rau hauv feem ntau siv rauv siv, txij li thaum 310S yog ib tug tsawg- carbon qib nrog zoo kuj rau weld - hais txog rhiab heev. Yog tias cov cuab yeej yuav pom cov kev pabcuam txuas ntxiv hauv sigma-theem- ua ntau yam, ib ntus kev daws teeb meem anneal - tsis yog kev ntxhov siab - yog qhov kev kho kom tsim nyog, tsis yog qhov kev ua haujlwm niaj hnub-weld yuav tsum tau.
Q: Dab tsi yog qhov ntsuas qhov ntsuas kub rau kev ua haujlwm txuas ntxiv 310S?
A: Kwv yees li ntawm 2,000℃F (1,093 degree) rau kev pabcuam oxidizing tas li, nrog rau qhov caveat tias cov khoom siv caij tsheb kauj vab los ntawm 1,200–1,650℃F (650–900 degree) ntau zaus raug rau sigma{10}}theem{ embrittlement dhau sijhawm 1.
Q: Vim li cas nickel cov ntsiab lus tseem ceeb heev rau carburization tsis kam?
A: Cov pa roj carbon muaj tsawg heev solubility nyob rau hauv npib tsib xee thiab diffuses rau hauv nws maj mam dua rau hauv hlau los yog chromium. Vim tias Incoloy 800H nqa kwv yees li 30-35% npib tsib xee piv rau kwv yees li 19-22% rau 310S, carbon nkag mus rau nws qhov chaw qeeb dua nyob rau hauv cov xwm txheej carburizing zoo ib yam, uas yog qhov laj thawj tseem ceeb ntawm 800H outperforms 310-tsev neeg stainless hlau hauv carburizing furnace cua.
