Stainless hlau yog dab tsi?
'Stainless' yog ib lo lus tau tsim thaum ntxov hauv kev tsim cov hlau no rau kev siv cutlery. Nws tau txais los ua lub npe dav dav rau cov hlau no thiab tam sim no npog ntau hom hlau thiab qib rau corrosion lossis oxidation resistant daim ntaub ntawv.
Stainless hlau yog hlau alloys nrog tsawg kawg yog 10.5% chromium. Lwm cov ntsiab lus alloying ntxiv los txhim kho lawv cov qauv thiab cov khoom xws li formability, lub zog thiab cryogenic toughness.
Cov qauv siv lead ua no ua rau cov hlau tsis muaj hlau nplaum thiab tsis muaj nkig ntawm qhov kub thiab txias. Rau siab dua hardness thiab lub zog, carbon ntxiv. Thaum tau txais kev kho cua sov kom txaus, cov hlau no yog siv los ua chais hniav, cutlery, cuab yeej thiab lwm yam.
Qhov tseem ceeb ntawm manganese tau siv nyob rau hauv ntau cov khoom siv stainless hlau. Manganese khaws cov qauv austenitic hauv cov hlau xws li npib tsib xee, tab sis ntawm tus nqi qis.
Cov ntsiab lus tseem ceeb hauv stainless hlau
Stainless hlau los yog corrosion-resistant steel yog ib hom hlau alloy uas muaj nyob rau hauv ntau hom. Nws pab peb cov kev xav tau zoo heev uas nws nyuaj rau nrhiav tau ib qho chaw ntawm peb lub neej, qhov twg peb tsis siv hom hlau no. Cov khoom tseem ceeb ntawm stainless hlau yog: hlau, chromium, carbon, npib tsib xee, molybdenum thiab lwm yam hlau me me.
Cov no muaj xws li hlau xws li:
- Nickel
- Molybdenum
- Titanium
- Tooj
Tsis yog-hlau ntxiv kuj tau ua, cov tseem ceeb yog:
- Cov pa roj carbon
- Nitrogen
CHROMIUM thiab NICKEL:
Chromium yog cov khoom uas ua rau cov hlau tsis muaj stainless. Nws yog ib qho tseem ceeb hauv kev tsim cov yeeb yaj kiab passive. Lwm cov ntsiab lus tuaj yeem cuam tshuam cov txiaj ntsig ntawm chromium hauv kev tsim lossis tswj cov yeeb yaj kiab, tab sis tsis muaj lwm yam khoom los ntawm nws tus kheej tuaj yeem tsim cov khoom ntawm stainless hlau.
Ntawm li 10.5% chromium, ib zaj duab xis tsis muaj zog yog tsim thiab yuav muab kev tiv thaiv cua sov. Los ntawm kev nce cov chromium mus rau 17-20%, uas yog ib txwm nyob rau hauv hom-300 series ntawm austenitic stainless hlau, kev ruaj ntseg ntawm cov yeeb yaj kiab passive yog nce. Kev nce ntxiv hauv cov ntsiab lus chromium yuav muab kev tiv thaiv ntxiv.
| Cim | Element |
| Al | Aluminium |
| C | Cov pa roj carbon |
| Cr | Chromium |
| Cu | Tooj |
| Fe | Hlau |
| Mo | Molybdenum |
| Mn | Manganese |
| N | Nitrogen |
| Ni | Nickel |
| P | Phosphorous |
| S | Sulfur |
| Se | Selenium |
| Ta | Tantalum |
| Ti | Titanium |
Nickel yuav ruaj khov rau cov qauv austenitic (cov nplej lossis cov qauv siv lead ua) ntawm cov hlau tsis muaj steel thiab txhim kho cov khoom siv thiab cov khoom tsim. Cov ntsiab lus npib tsib xee ntawm 8-10% thiab siab dua yuav txo qhov nyiam ntawm cov hlau kom tawg vim kev ntxhov siab corrosion. Nickel kuj txhawb kev rov ua dua thaum cov yeeb yaj kiab puas.
MANGANESE:
Manganese, nyob rau hauv kev koom tes nrog npib tsib xee, ua ntau yam ntawm lub luag hauj lwm los ntawm nickel. Nws tseem yuav cuam tshuam nrog cov leej faj hauv cov hlau tsis muaj hlau los tsim manganese sulfites, uas ua rau muaj kev tiv thaiv pitting corrosion. Los ntawm kev hloov manganese rau npib tsib xee, thiab tom qab ntawd sib xyaw nrog nitrogen, lub zog kuj nce ntxiv.
MOLYBDENUM:
Molybdenum, ua ke nrog chromium, zoo heev rau stabilizing cov zaj duab xis passive nyob rau hauv lub xub ntiag ntawm chlorides. Nws muaj txiaj ntsig zoo los tiv thaiv crevice lossis pitting corrosion. Molybdenum, ib sab ntawm chromium, muab qhov loj tshaj plaws ntawm kev tiv thaiv corrosion hauv stainless hlau. Edstrom Industries siv 316 stainless vim nws muaj 2-3% molybdenum, uas muab kev tiv thaiv thaum ntxiv chlorine rau hauv dej.
CARBON:
Carbon yog siv los ua kom muaj zog. Hauv qib martensitic, qhov sib ntxiv ntawm cov pa roj carbon monoxide ua kom tawv tawv los ntawm kev kho cua sov.
NITROGEN:
Nitrogen yog siv los ua kom ruaj khov austenitic qauv ntawm stainless hlau, uas txhim kho nws cov tsis kam rau pitting corrosion thiab ntxiv dag zog rau cov hlau. Siv cov nitrogen ua rau nws muaj peev xwm nce cov ntsiab lus molybdenum mus txog 6%, uas txhim kho corrosion kuj nyob rau hauv ib puag ncig chloride.
Titanium thiab MIOBIUM:
Titanium thiab Miobium yog siv los txo qhov rhiab heev ntawm stainless hlau. Thaum stainless hlau yog rhiab heev, intergranular corrosion tuaj yeem tshwm sim. Qhov no yog tshwm sim los ntawm nag lossis daus ntawm chrome carbides thaum lub caij txias thaum cov khoom welded. Qhov no depletes thaj tsam weld ntawm chromium. Yog tsis muaj chromium, zaj duab xis passive tsis tuaj yeem tsim. Titanium thiab Niobium cuam tshuam nrog cov pa roj carbon monoxide los tsim cov carbide, tawm hauv cov chromium hauv kev daws kom cov zaj duab xis passive tuaj yeem tsim.
Tooj thiab Aluminum:
Tooj thiab Aluminium, nrog rau titanium, tuaj yeem muab ntxiv rau cov hlau tsis muaj steel kom precipitate nws hardening. Hardening yog ua tiav los ntawm kev ntub dej ntawm qhov kub ntawm 900 txog 1150F. Cov ntsiab lus no tsim ib qho nyuaj intermetallic microstructure thaum lub sij hawm soaking ntawm qhov kub siab.
Sulfur thiab selenium:
Sulfur thiab Selenium ntxiv rau 304 stainless kom nws tshuab dawb. Qhov no dhau los ua 303 lossis 303SE stainless hlau, uas yog siv los ntawm Edstrom Industries los ua hog li qub, txiv ntseej, thiab qhov chaw uas tsis raug rau cov dej haus.
Hom stainless hlau
LUB AISI txhais cov qib hauv qab no ntawm lwm tus:
Kuj hu ua "marine qib" stainless hlau vim nws muaj peev xwm tiv taus cov dej ntsev corrosion piv rau hom 304. SS316 feem ntau yog siv los tsim cov nroj tsuag nuclear reprocessing.
304/304L Stainless hlau
Hom 304 muaj lub zog qis dua li 302 vim nws cov ntsiab lus qis dua.
316/316L Stainless hlau
Hom 316/316L Stainless Hlau yog ib qho molybdenum hlau uas muaj kev txhim kho rau pitting los ntawm kev daws teeb meem uas muaj chlorides thiab lwm yam halides.
310S STAINLESS HLAU STEEL
310S Stainless hlau muaj kev tiv thaiv zoo heev rau oxidation nyob rau hauv qhov kub thiab txias mus rau 2000 ° F.
317L Stainless hlau
317L yog molybdenum bearing austenitic chromium nickel steel zoo ib yam li hom 316, tshwj tsis yog cov ntsiab lus alloy hauv 317L yog me ntsis siab dua.
321/321H STAINLESS HLAU STEEL
Hom 321 yog hom 304 hloov kho los ntawm kev ntxiv titanium hauv qhov tsawg kawg yog 5 npaug ntawm cov pa roj carbon ntxiv rau cov ntsiab lus nitrogen.
410 Stainless hlau
Hom 410 yog martensitic stainless hlau uas yog hlau nplaum, tiv thaiv corrosion nyob rau hauv ib puag ncig me me thiab muaj qhov zoo ductility.
DUPLEX 2205 (UNS S31803)
Duplex 2205 (UNS S31803), lossis Avesta Sheffield 2205 yog ferritic-austenitic stainless hlau.
STAINLESS HLAU STAINLESS HLAU TSEEM CEEB NTAWM LUB CRYSTALLINE STRUCTURE:
- Austenitic stainless hlau muaj ntau dua 70% ntawm tag nrho cov hlau stainless ntau lawm. Lawv muaj qhov siab tshaj plaws ntawm 0.15% carbon, tsawg kawg yog 16% chromium thiab txaus npib tsib xee thiab / lossis manganese kom khaws cov qauv austenitic ntawm txhua qhov kub ntawm thaj tsam cryogenic mus rau qhov chaw melting ntawm cov hlau. Ib tug raug muaj pes tsawg leeg yog 18% chromium thiab 10% npib tsib xee, feem ntau hu ua 18/10 stainless yog feem ntau siv nyob rau hauv flatware. Ib yam li 18/0 thiab 18/8 kuj muaj. ¨Superaustenitic 〃 stainless hlau, xws li alloy AL-6XN thiab 254SMO, muaj kev tiv thaiv zoo rau cov tshuaj chloride pitting thiab crevice corrosion vim siab Molybdenum cov ntsiab lus (> 6%) thiab nitrogen ntxiv thiab cov ntsiab lus nickel siab dua kom ntseeg tau zoo dua rau kev ntxhov siab-corrosion tawg. ntau tshaj 300 series. Cov ntsiab lus siab dua ntawm "Superaustenitic" steels txhais tau tias lawv muaj kev ntshai kim thiab kev ua haujlwm zoo sib xws tuaj yeem ua tiav siv cov hlau duplex ntawm tus nqi qis dua.
- Ferritic stainless hlau yog cov tshuaj tiv thaiv corrosion heev, tab sis nyob deb tsawg dua li qib austenitic thiab tsis tuaj yeem ua kom tawv los ntawm kev kho cua sov. Lawv muaj nyob nruab nrab ntawm 10.5% thiab 27% chromium thiab nickel tsawg heev, yog tias muaj. Feem ntau cov muaj xws li molybdenum; ib co, aluminium los yog titanium. Cov qib ferritic feem ntau suav nrog 18Cr-2Mo, 26Cr-1Mo, 29Cr-4Mo, thiab 29Cr-4Mo-2Ni.
- Martensitic stainless hlau tsis zoo li corrosion resistant li lwm yam ob chav kawm, tab sis tsis tshua muaj zog thiab tawv zoo li machineable heev, thiab tuaj yeem hardened los ntawm kev kho cua sov. Martensitic stainless hlau muaj chromium (12-14%), molybdenum (0.2-1%), tsis muaj nickel, thiab li 0.1-1% carbon (muab nws hardness ntau dua tab sis ua rau cov khoom me ntsis nkig). Nws yog quenched thiab sib nqus. Nws tseem hu ua "series-00" steel.
- Duplex stainless steels muaj ib tug sib xyaw microstructure ntawm austenite thiab ferrite, lub hom phiaj yog los tsim ib tug 50:50 mix txawm nyob rau hauv kev lag luam alloys cov mix tej zaum yuav yog 60:40. Duplex steel tau txhim kho lub zog ntawm austenitic stainless hlau thiab kuj txhim kho kev tiv thaiv rau hauv zos corrosion tshwj xeeb pitting, crevice corrosion thiab kev ntxhov siab corrosion tawg. Lawv yog cov yam ntxwv los ntawm siab chromium thiab qis nickel cov ntsiab lus tshaj austenitic stainless hlau.
Keeb kwm ntawm Stainless Hlau
Ob peb corrosion-resistant hlau artifacts ciaj sia los ntawm antiquity. Ib qho piv txwv nto moo (thiab loj heev) yog Iron Pillar ntawm Delhi, tsim los ntawm kev txiav txim ntawm Kumara Gupta I nyob ib ncig ntawm lub xyoo AD 400. Txawm li cas los xij, tsis zoo li cov hlau tsis muaj steel, cov khoom cuav no tshuav lawv cov kav ntev tsis yog chromium, tab sis rau lawv cov ntsiab lus phosphorus siab, uas ua ke nrog cov huab cua zoo hauv zos txhawb kev tsim cov khoom tiv thaiv passivation txheej ntawm hlau oxides thiab phosphates, es tsis muaj kev tiv thaiv, tawg xeb txheej uas tsim los ntawm cov hlau feem ntau.
Qhov kev tiv thaiv corrosion ntawm hlau-chromium alloys tau pom thawj zaug hauv xyoo 1821 los ntawm Fabkis metallurgist Pierre Berthier, uas tau sau tseg tias lawv tsis kam tawm tsam los ntawm qee cov kua qaub thiab qhia lawv siv hauv cutlery. Txawm li cas los xij, metallurgists ntawm lub xyoo pua 19th tsis tuaj yeem tsim kev sib xyaw ua ke ntawm cov pa roj carbon tsawg thiab cov chromium siab nyob rau hauv cov hlau tsis muaj steel niaj hnub no, thiab cov high-chromium alloys lawv tuaj yeem tsim tau nkig dhau los ua kev txaus siab.
Qhov xwm txheej no tau hloov pauv thaum xyoo 1890s, thaum Hans Goldschmidt ntawm lub teb chaws Yelemees tsim cov txheej txheem aluminothermic (thermite) rau kev tsim cov pa roj carbon tsis muaj chromium. Nyob rau xyoo 1904 thiab xyoo 1911, ntau tus kws tshawb fawb, tshwj xeeb yog Leon Guillet ntawm Fabkis, tau npaj cov alloys uas niaj hnub no suav tias yog stainless hlau. Xyoo 1911, Philip Monnartz ntawm Lub Tebchaws Yelemees tau tshaj tawm txog kev sib raug zoo ntawm cov ntsiab lus chromium thiab corrosion kuj ntawm cov alloys.
Harry Brearley ntawm Brown-Firth kev tshawb fawb kuaj hauv Sheffield, England feem ntau suav tias yog "tus tsim khoom" ntawm stainless
hlau. Nyob rau hauv 1913, thaum nrhiav ib tug erosion-resistant alloy rau phom phom, nws nrhiav tau thiab tom qab industrialized ib tug martensitic stainless hlau alloy. Txawm li cas los xij, cov kev lag luam zoo sib xws tau tshwm sim nyob rau ib ntus ntawm Krupp Iron Works hauv Tebchaws Yelemees, qhov chaw Eduard Maurer thiab Benno Strauss tau tsim cov austenitic alloy (21% chromium, 7% nickel), thiab hauv Tebchaws Meskas, qhov chaw Christian Dantsizen thiab Frederick Becket. yog industrializing ferritic stainless.
Thov nco ntsoov tias tej zaum koj yuav txaus siab rau lwm cov ntawv xov xwm uas peb tau tshaj tawm:
Post lub sij hawm: Jun-16-2022