Stainless hlau (Stainless hlau)yog cov ntawv luv ntawm stainless acid-resistant steel, thiab cov qib steel uas tiv taus tsis muaj zog corrosive media xws li huab cua, chav dej, dej, lossis muaj cov khoom tsis zoo yog hu ua stainless hlau.
Lub sij hawm "stainless hlau" tsis yog tsuas yog xa mus rau ib hom stainless hlau, tab sis hais txog ntau tshaj li ib puas hom kev lag luam stainless hlau, txhua tus muaj kev ua tau zoo hauv nws cov ntawv thov tshwj xeeb.
Lawv txhua tus muaj 17 mus rau 22% chromium, thiab cov qib hlau zoo dua kuj muaj cov npib tsib xee.Ntxiv molybdenum tuaj yeem txhim kho atmospheric corrosion, tshwj xeeb tshaj yog tiv thaiv corrosion hauv chloride-muaj cua.
Ib.Classification ntawm stainless hlau
1. Stainless hlau thiab acid-resistant steel yog dab tsi?
Teb: Stainless hlau yog cov ntawv luv ntawm stainless acid-resistant steel, uas yog resistant rau tsis muaj zog corrosive media xws li cua, chav, dej, los yog stainless hlau.Corroded steel qib yog hu ua acid-resistant steels.
Vim qhov sib txawv ntawm cov tshuaj muaj pes tsawg leeg ntawm ob, lawv cov corrosion kuj sib txawv.Ordinary stainless hlau feem ntau tsis resistant rau tshuaj nruab nrab corrosion, thaum acid-resistant steel feem ntau stainless.
2. Yuav ua li cas cais stainless hlau?
Teb: Raws li lub koom haum lub xeev, nws tuaj yeem muab faib ua martensitic steel, ferritic steel, austenitic steel, austenitic-ferritic (duplex) stainless hlau thiab nag lossis daus hardening stainless hlau.
(1) Martensitic steel: siab zog, tab sis tsis zoo plasticity thiab weldability.
Feem ntau siv cov qib martensitic stainless hlau yog 1Cr13, 3Cr13, thiab lwm yam., vim muaj cov ntsiab lus carbon siab, nws muaj lub zog siab, hardness thiab hnav tsis kam, tab sis corrosion kuj yog me ntsis tsis zoo, thiab nws yog siv rau cov khoom siv kho mob siab thiab corrosion kuj.Qee qhov dav dav yuav tsum tau ua, xws li cov springs, chav turbine hniav, hydraulic xovxwm li qub, thiab lwm yam.
Cov hlau no yog siv tom qab quenching thiab tempering, thiab annealing yuav tsum tau tom qab forging thiab stamping.
(2) Ferritic hlau: 15% mus rau 30% chromium.Nws cov corrosion kuj, toughness thiab weldability nce nrog nce ntawm cov ntsiab lus chromium, thiab nws cov chloride kev nyuaj siab corrosion yog zoo dua li lwm hom stainless hlau, xws li Crl7, Cr17Mo2Ti, Cr25, Cr25Mo3Ti, Cr28, thiab lwm yam.
Vim nws cov ntsiab lus chromium siab, nws cov corrosion kuj thiab oxidation kuj zoo, tab sis nws cov khoom siv thiab cov txheej txheem tsis zoo.Nws feem ntau yog siv rau cov qauv acid-resistant nrog me ntsis kev ntxhov siab thiab ua cov hlau los tiv thaiv oxidation.
Cov hlau no tuaj yeem tiv taus qhov corrosion ntawm huab cua, nitric acid thiab ntsev tov, thiab muaj cov yam ntxwv ntawm qhov kub thiab txias oxidation tsis kam thiab me me thermal expansion coefficient.Nws yog siv nyob rau hauv nitric acid thiab khoom noj khoom haus Hoobkas khoom, thiab kuj yuav siv tau los ua qhov chaw uas ua hauj lwm ntawm kub kub, xws li roj turbine qhov chaw, thiab lwm yam.
(3) Austenitic steel: Nws muaj ntau dua 18% chromium, thiab tseem muaj txog 8% npib tsib xee thiab ib qho me me ntawm molybdenum, titanium, nitrogen thiab lwm yam khoom.Kev ua tau zoo tag nrho, tiv taus corrosion los ntawm ntau yam xov xwm.
Feem ntau, kev kho kev daws teeb meem yog saws, uas yog, cov hlau yog rhuab mus rau 1050-1150 ° C, thiab tom qab ntawd dej-txias lossis cua-txias kom tau txais ib theem austenite qauv.
(4) Austenitic-ferritic (duplex) stainless hlau: Nws muaj qhov zoo ntawm ob qho tib si austenitic thiab ferritic stainless hlau, thiab muaj superplasticity.Austenite thiab ferrite txhua tus account rau ib nrab ntawm cov hlau tsis muaj steel.
Hauv cov ntsiab lus C tsawg, cov ntsiab lus Cr yog 18% txog 28%, thiab Ni cov ntsiab lus yog 3% txog 10%.Qee cov hlau kuj tseem muaj cov alloying xws li Mo, Cu, Si, Nb, Ti, thiab N.
Cov hlau no muaj cov yam ntxwv ntawm ob qho tib si austenitic thiab ferritic stainless hlau.Piv nrog rau ferrite, nws muaj ntau dua plasticity thiab toughness, tsis muaj chav kub brittleness, ho txhim kho intergranular corrosion kuj thiab vuam kev ua tau zoo, thaum tuav hlau Lub cev stainless hlau yog nkig ntawm 475 ° C, muaj thermal conductivity, thiab muaj cov yam ntxwv ntawm superplasticity. .
Piv nrog rau austenitic stainless hlau, nws muaj lub zog siab thiab txhim kho kev ua haujlwm zoo rau intergranular corrosion thiab chloride stress corrosion.Duplex stainless hlau muaj zoo heev pitting corrosion kuj thiab kuj yog ib tug nickel-txuag stainless hlau.
(5) Cov nag lossis daus hardening stainless hlau: lub matrix yog austenite los yog martensite, thiab cov qib siv feem ntau ntawm nag lossis daus hardening stainless hlau yog 04Cr13Ni8Mo2Al thiab lwm yam.Nws yog cov hlau tsis muaj steel uas tuaj yeem ua kom muaj zog (muaj zog) los ntawm nag lossis daus hardening (tseem hu ua hnub nyoog hardening).
Raws li muaj pes tsawg leeg, nws tau muab faib ua chromium stainless hlau, chromium-nickel stainless hlau thiab chromium manganese nitrogen stainless hlau.
(1) Chromium stainless hlau muaj qee yam kev tiv thaiv corrosion (oxidizing acid, organic acid, cavitation), kub tsis kam thiab hnav tsis kam, thiab feem ntau yog siv los ua cov khoom siv rau cov chaw nres tsheb fais fab, tshuaj, thiab roj av.Txawm li cas los xij, nws qhov weldability tsis zoo, thiab kev saib xyuas yuav tsum tau them rau cov txheej txheem vuam thiab kev kho cua sov.
(2) Thaum lub sij hawm vuam, chromium-nickel stainless hlau yog raug rov ua cua sov rau precipitate carbides, uas yuav txo tau corrosion kuj thiab txhua yam khoom.
(3) Lub zog, ductility, toughness, formability, weldability, hnav tsis kam thiab corrosion kuj ntawm chromium-manganese stainless hlau yog zoo.
二.Cov teeb meem nyuaj hauv stainless hlau vuam thiab qhia txog kev siv cov khoom siv thiab cov khoom siv
1. Vim li cas vuam stainless hlau nyuaj?
Teb: (1) Thaum tshav kub kub rhiab heev ntawm stainless hlau kuj muaj zog, thiab lub sij hawm nyob rau hauv qhov kub thiab txias ntawm 450-850 ° C yog me ntsis ntev, thiab corrosion kuj ntawm weld thiab tshav kub-tshuaj tiv thaiv cheeb tsam yuav raug txo heev;
(2) ua rau thermal tawg;
(3) Kev tiv thaiv tsis zoo thiab kub kub oxidation hnyav heev;
(4) Lub linear expansion coefficient yog loj, thiab nws yog ib qho yooj yim los tsim loj vuam deformation.
2. Yuav ua li cas cov cuab yeej siv tau zoo rau kev vuam austenitic stainless hlau?
Teb: (1) nruj me ntsis xaiv vuam cov ntaub ntawv raws li cov tshuaj muaj pes tsawg leeg ntawm lub hauv paus hlau;
(2) welding ceev nrog me me tam sim no, cov kab me me zog txo cov cua sov nkag;
(3) Nyias txoj kab uas hla vuam hlau, vuam pas nrig, tsis muaj viav vias, ntau txheej multi-pass vuam;
(4) Kev quab yuam txias ntawm cov vuam seam thiab tshav kub-cuam tshuam cheeb tsam kom txo tau lub sij hawm nyob ntawm 450-850 ° C;
(5) Argon tiv thaiv nyob rau sab nraum qab ntawm TIG vuam;
(6) Cov welds nyob rau hauv kev sib cuag nrog corrosive nruab nrab yog thaum kawg welded;
(7) Passivation kho ntawm weld seam thiab tshav kub-cuam tshuam cheeb tsam.
3. Vim li cas peb yuav tsum xaiv 25-13 series vuam hlau thiab electrode rau vuam austenitic stainless hlau, carbon hlau thiab hlau tsis tshua muaj hlau (dissimilar steel vuam)?
Teb: Vuam tsis sib xws steel welded pob qij txha txuas austenitic stainless hlau nrog cov pa roj carbon steel thiab cov hlau tsis tshua muaj hlau, cov hlau tso nyiaj yuav tsum siv 25-13 series vuam hlau (309, 309L) thiab vuam pas nrig (Austenitic 312, Austenitic 307, thiab lwm yam).
Yog tias lwm yam khoom siv hlau tsis huv siv tau siv, cov qauv martensitic thiab cov kab nrib pleb txias yuav tshwm sim ntawm fusion kab ntawm sab ntawm cov hlau thiab cov hlau tsis tshua muaj hlau.
4. Vim li cas cov hlau tsis muaj hlau vuam hlau siv 98% Ar + 2% O2 shielding gas?
Teb: Thaum lub sij hawm MIG welding ntawm cov khoom stainless hlau xaim, yog cov roj ntshiab argon siv los tiv thaiv, qhov nro ntawm lub pas dej molten yog siab, thiab cov welded tsis zoo, uas qhia tau hais tias "humpback" weld zoo.Ntxiv 1 mus rau 2% oxygen tuaj yeem txo qhov nro ntawm lub pas dej molten, thiab cov vuam seam yog du thiab zoo nkauj.
5. Vim li cas qhov saum npoo ntawm cov khoom stainless hlau vuam hlau MIG vuam tig dub?Yuav daws qhov teeb meem no li cas?
Teb: MIG vuam ceev ntawm cov khoom stainless hlau vuam hlau yog ceev ceev (30-60cm / min).Thaum cov roj tiv thaiv nozzle tau khiav mus rau pem hauv ntej molten pas dej ua ke, lub vuam seam tseem nyob rau hauv ib tug liab-kub high-kub lub xeev, uas yog yooj yim oxidized los ntawm huab cua, thiab oxides yog tsim nyob rau saum npoo.Welds yog dub.Txoj kev pickling passivation tuaj yeem tshem tawm cov tawv nqaij dub thiab kho cov xim qub ntawm cov hlau tsis huv.
6. Vim li cas cov hlau tsis muaj steel hlau yuav tsum tau siv lub zog hluav taws xob kom ua tiav lub dav hlau hloov pauv thiab tsis muaj spatter-welding?
Teb: Thaum cov khoom hlau stainless hlau MIG vuam, φ1.2 vuam hlau, thaum tam sim no kuv ≥ 260 ~ 280A, lub dav hlau hloov pauv tuaj yeem ua tiav;lub droplet yog luv luv-circuit hloov nrog tsawg tshaj li qhov no tus nqi, thiab lub spatter yog loj, feem ntau tsis pom zoo.
Tsuas yog los ntawm kev siv MIG fais fab mov nrog mem tes, tuaj yeem hloov pauv cov mem tes ntawm me me mus rau qhov loj specification (xaiv qhov tsawg kawg nkaus lossis siab tshaj tus nqi raws li txoj kab uas hla ntawm cov xaim), spatter-free welding.
7. Vim li cas qhov flux-cored stainless hlau vuam hlau tiv thaiv los ntawm CO2 roj es tsis txhob siv lub zog hluav taws xob?
Teb: Tam sim no feem ntau siv flux-cored stainless hlau vuam hlau (xws li 308, 309, thiab lwm yam), welding flux formula nyob rau hauv vuam hlau yog tsim raws li cov welding tshuaj metallurgical cov tshuaj tiv thaiv nyob rau hauv kev tiv thaiv ntawm CO2 roj, yog li feem ntau , tsis tas yuav muaj cov khoom siv hluav taws xob arc vuam (Lub zog hluav taws xob nrog cov mem tes yeej xav tau siv cov roj sib xyaw), yog tias koj xav nkag mus rau qhov hloov pauv ua ntej, koj tuaj yeem siv lub zog hluav taws xob los yog cov pa roj tiv thaiv vuam qauv nrog sib xyaw roj welding.
Post lub sij hawm: Mar-24-2023