1.4404 vs 1.4509 Stainless hlau: Cov khoom sib piv thiab cov lus qhia xaiv

1.4404 thiab 1.4509: Ob Tsev Neeg, Ob Txoj Kev Tsim Qauv

Kev xaiv ntawm 1.4404 (316L) thiab 1.4509 (441) txhais tau tias xaiv ntawm austenitic thiab ferritic stainless hlau. Ob qib ua haujlwm sib txawv ntawm lub hom phiaj engineering: 1.4404 yog siab - xeb- qib austenitic rau cov txheej txheem welded, thaum 1.4509 yog tus nqi qis, qis- nickel ferritic qib tsim rau automotive qhov chaw siab tshaj qhov kev siv hluav taws xob thiab kev siv hluav taws xob ntau dua.

1.4404 (X2CrNiMo17-12-2) yog dab tsi?

1.4404, tseem hu ua AISI 316L thiab UNS S31603, yog austenitic stainless hlau nrog molybdenum ntxiv ntawm 2.0-2.5% rau kev txhim kho cov tshuaj chlorides thiab pitting. Nws cov ntsiab lus carbon yog txwv rau 0.030% siab tshaj plaws, uas tiv thaiv chromium carbide nag lossis daus ntawm cov ciam teb thiab ua rau cov hlau tiv taus intergranular corrosion tom qab vuam. Qib yog non-magnetic, ductile heev, thiab haum rau kev ua zaub mov, chemical plant, marine fittings thiab heat exchangers.

1.4509 (X2CrTiNb18) yog dab tsi?

1.4509, hu ua AISI 441, yog ferritic stainless hlau nrog cov ntsiab lus chromium ntawm 17.5-18.5% thiab npib tsib xee tsawg heev. Nws yog dual-stabilized nrog titanium thiab niobium, uas khi cov pa roj carbon thiab nitrogen kom cov hlau resists intergranular corrosion tsis tas yuav tsum muaj cov ntsiab lus carbon tsawg. Cov qauv ferritic ua rau qib sib nqus. Nws muaj qhov zoo oxidation tsis kam ntawm qhov kub thiab txias thiab yog cov khoom siv rau kev siv lub tsheb tso pa tawm, downpipes thiab catalytic converter vaj tse, nrog rau cov khoom siv hauv chav ua noj thiab lub tsev sab hauv.

Kev sib piv Chemical Composition (EN 10088-2)

Cov ntsiab lus,%	1.4404	1.4509
Cov pa roj carbon C	0.030 max	0.030 max
Silicon Si	max 1.00 Nws	max 1.00 Nws
Manganese Mn	max 2.00 Nws	max 1.00 Nws
Phosphorus P	0.045 max	0.040 max
Sulfur S	0.030 max	0.015 max
Chromium Cr	16.5-18.5	17.5-18.5
Nickel Nim	10.0-13.0	qhov tseem ceeb tsis muaj
Molybdenum Cov	2.0-2.5	-
Niobium Nb	-	0.30-1.00
Titanium Ti	-	stabilizing ntxiv

Mechanical thiab Physical Properties

Khoom	1.4404	1.4509
Microstructure	Austenitic, tsis yog{0}}magnetic	Ferritic, sib nqus
Qhov ceev, g / cm3	7.93	7.70
0.2% pov thawj kev ntxhov siab Rp0.2, MPa	240 feeb	230 feeb
Tensile zog Rm, MPa	530-680	430-630
Elongation A,%	40 feeb	20 feeb
Hom PREN	24-26	18-20
Ua kom siab -kub muaj peev xwm	Kev pabcuam txuas ntxiv mus txog 870 C	Kev pabcuam cuam tshuam txog li 950 C

Cov txiaj ntsig ua raws EN 10088-2 rau daim ntawv thiab strip txog li 8 hli thickness nyob rau hauv cov tshuaj-annealed mob. PREN (Cr + 3.3 Mo + 16 N) yog qhov ntsuas pitting tsis kam hauv cov tshuaj chloride.

Weldability thiab Fabrication

1.4404 welds tau yooj yim los ntawm txhua tus txheej txheem txheej txheem thiab xav tau tsis muaj kev tshaj tawm -weld heat treatment vim nws cov ntsiab lus carbon tsawg, uas ua rau nws zoo tagnrho rau welded siab hlab ntsha, tso tsheb hlau luam thiab pipework . 1.4509 kuj yog weldable, tab sis cov qauv ferritic yog rhiab heev rau grain loj hlob nyob rau hauv lub tshav kub - cuam tshuam cheeb tsam ntawm high heat input. Vuam ntawm 1.4509 yuav tsum siv cov hluav taws xob qis thiab, yog tias ua tau, niobium-cov kabmob muab tub lim hlau, txhawm rau khaws cov tawv thiab corrosion kuj. Hauv kev tsim, 1.4404 ua haujlwm- hardens sai dua li qib ferritic, thaum 1.4509 muaj qhov sib sib zog nqus zoo heev -kev coj cwj pwm thiab qis qis.

Kev Taw Qhia Xaiv

Xaiv 1.4404 thaum cov khoom sib txuas yog welded thiab yuav raug cov tshuaj chlorides, txheej txheem tshuaj, dej hiav txwv txaws los yog khoom noj khoom haus, los yog thaum lub siab - lub nkoj kev ntseeg siab thiab siab ductility yuav tsum tau.

Xaiv 1.4509 thaum daim ntawv thov raug nqi-rhiab heev, xav tau cov lus teb sib nqus, xav tau oxidation tsis kam mus rau 950 degrees Celsius hauv kev pabcuam sib cuam tshuam, lossis koom nrog kev sib sib zog nqus ntawm daim ntawv nyias, xws li cov tshuab tso pa thiab cov khoom siv hauv tsev.

Cov lus nug nquag

Q1. Puas yog 1.4509 pheej yig dua 1.4404?

Yog lawm, feem ntau . 1.4509 muaj yuav luag tsis muaj npib tsib xee, thiab npib tsib xee yog cov khoom kim tshaj plaws nyob rau hauv stainless hlau. Cov qib ferritic yog li ntawd pheej yig dua, uas yog ib qho tseem ceeb vim li cas nws dominates automotive tso tsheb hlau luam thiab cov khoom siv.

Q2. Yog 1.4509 magnetic?

Yog. 1.4509 muaj ferritic (lub cev-centered cubic) qauv) thiab yog sib nqus txawm tias tom qab ua haujlwm txias lossis vuam, tsis zoo li qib austenitic xws li 1.4404 uas yog qhov tseem ceeb tsis yog- hlau nplaum.

Q3. Qib twg tiv cov chlorides zoo dua?

1.4404 ib. 2.0-2.5% molybdenum cov ntsiab lus muab nws PREN txog 24-26 piv rau 18-20 rau 1.4509, thiab zoo dua rau pitting thiab crevice corrosion nyob rau hauv chloride ib puag ncig. Rau cov dej hiav txwv immersion, txawm tias qib siab-alloy yog xav tau.

Q4. Puas yog 1.4404 thiab 316L yog cov khoom qub?

Yog. 1.4404 yog EN cov ntaub ntawv tus lej, X2CrNiMo17-12-2 yog EN steel lub npe, thiab AISI 316L / UNS S31603 yog Asmeskas cov qauv tsim ntawm tib qib qis carbon austenitic.

Q5. 1.4509 puas tuaj yeem siv rau qhov kub thiab txias?

1.4509 muaj qhov zoo oxidation tsis kam mus txog li 950 degrees Celsius hauv kev pabcuam cuam tshuam thiab yog cov khoom siv rau kev siv lub tshuab ua pa. Nws lub zog creep yog txwv, yog li thauj khoom -cov kabmob siab- qhov kub thiab txias tsim yuav tsum tau kuaj xyuas cov ntaub ntawv cuam tshuam.

Q6. Dab tsi yog qhov txiaj ntsig tseem ceeb ntawm 1.4404 tshaj 1.4509 hauv cov khoom siv welded?

Cov ntsiab lus qis ntawm 1.4404 tiv thaiv kev nkag siab, yog li cov pob qij txha welded khaws tag nrho corrosion tsis kam tom qab-weld kev kho cua sov. 1.4509 tso siab rau titanium thiab niobium stabilization, uas yuav tsum tau ua tib zoo vuam xyaum kom tsis txhob muaj qoob loo loj hlob thiab chromium -depleted aav.