304 vs 304L Stainless hlau: Qhov qis -Kev xaiv carbon rau Weldability

 

1. Cov ntsiab lus tseem ceeb, kev ua tau zoo thiab kev siv ntawm 304 thiab 304L yog dab tsi?

304 (UNS S30400) muaj 18-20% Cr, 8-10.5% Ni, thiab tsawg dua los yog sib npaug rau 0.08% C, nrog zoo corrosion kuj thiab formability. Nws yog siv rau cov khoom siv hauv chav ua noj, kev tsim vaj tsev, thiab cov khoom siv dav dav.304L (UNS S30403) muaj tsawg dua lossis sib npaug li 0.03% C, tsis txhob hnov ​​​​qab thaum vuam. Nws tuav 304 lub zog tab sis muaj kev nyab xeeb dua rau cov khoom siv welded xws li cov tso tsheb hlau luam thiab cov kav dej.

2. 304L daws qhov teeb meem vuam uas 304 ntsej muag li cas?

Thaum 304 yog welded, kub kub tuaj yeem ua rau chromium carbide nag lossis daus ntawm cov ciam teb, ua kom tsis muaj zog corrosion (sensitization). 304L cov ntsiab lus qis qis tiv thaiv cov nag lossis daus, yog li nws cov welds khaws cov corrosion tsis kam tom qab -weld heat treatment, simplifying fabrication.

3. Nyob rau hauv dab tsi scenarios yuav tsum tau xaiv 304L tshaj 304?

Xaiv 304L rau ib qho kev sib dhos welded (piv txwv li, cov hlab ntsha siab, cov kav dej ua zaub mov) qhov twg corrosion kuj tom qab vuam yog qhov tseem ceeb.Nws tseem nyiam rau cov haujlwm uas yuav tsum tau ua raws li cov qauv qis - cov khoom siv carbon hauv kev lag luam xws li tshuaj lossis petrochemicals.

4. Puas muaj kev lag luam tawm - tawm thaum siv 304L tsis yog 304?

304L muaj zog me ntsis qis dua 304 (lub zog tensile ~ 515MPa vs 304's ~ 550MPa), yog li nws tsis tshua zoo rau siab - kev ntxhov siab tsis yog - welded qhov chaw.Nws cov nqi ntawm cov khoom yog marginally siab dua (5-10%) vim kev tswj cov pa roj carbon ntau dua.

5. Dab tsi yog fabricators yuav tsum nco ntsoov thaum ua hauj lwm nrog 304 vs 304L?

Rau 304, welds xav tau tom qab-weld kev kho cua sov yog xav tau kev tiv thaiv corrosion; 304L hla cov kauj ruam no.Ob leeg muaj kev tsim tau zoo, tab sis 304 tuaj yeem ua haujlwm siab dua me ntsis txias ua haujlwm. Nco ntsoov xyuas cov ntaub ntawv pov thawj rau cov ntsiab lus carbon kom tsis txhob sib tov-ups.