430 Stainless Hlau (UNS S43000): Kev Lag Luam Ua Haujlwm ntawm Ferritic Qib

 

Dab tsi yog cov tshuaj lom neeg muaj pes tsawg leeg, cov khoom siv kho tshuab, thiab kev siv thawj zaug ntawm 430 stainless hlau?
Hom 430 yog ib tug ncaj chromium ferritic hlau nrog ib tug raug muaj pes tsawg leeg ntawm 16-18% chromium, tsawg dua 0.12% carbon, thiab tsis muaj npib tsib xee. Qhov no muaj pes tsawg leeg ua rau nws sib nqus thiab muab nws zoo tiv thaiv nitric acid, organic acids, thiab atmospheric corrosion. Mechanically, nws muaj lub zog nruab nrab, qis toughness dua qib austenitic, tab sis zoo heev tiv thaiv kev ntxhov siab corrosion cracking. Nws tsis yog hardenable los ntawm kev kho cua sov. Nws cov khoom siv tseem ceeb suav nrog cov khoom siv sab hauv (qhov cub qhov rooj, lub tub yees vaj huam sib luag), automotive decorative moldings, chav ua noj splashbacks, fasteners, thiab ntau yam kev lag luam thiab cov khoom vaj tsev uas raug mob me me thiab tus nqi yog qhov tseem ceeb.

Qhov kev tiv thaiv corrosion ntawm 430 piv rau 304 li cas, thiab nws cov kev txwv yog dab tsi?
Nyob rau hauv qhuav sab hauv los yog me me nyob deb nroog / nroog cua, 430 muaj kev txaus siab corrosion kuj piv rau 304 rau ntau daim ntawv thov. Txawm li cas los xij, nws qhov kev ua tau zoo sib txawv hauv qhov chaw nruj dua. Nws muaj kev tiv thaiv tsis zoo rau pitting thiab crevice corrosion hauv chloride-muaj cov chaw (cov cheeb tsam ntug dej hiav txwv, de-icing salts). Nws kuj tseem raug rau "intergranular corrosion" yog tias cua sov ntawm 400-900 degree, xws li hauv vuam, qhov twg chromium carbides tuaj yeem tsim ntawm cov ciam teb. Yog li ntawd, 430 tsis pom zoo rau kev tsim kho welded raug corrosive media los yog siv rau sab nrauv hauv kev nyab xeeb ntawm ntug dej hiav txwv.

Dab tsi yog nws qhov tseem ceeb fabrication yam ntxwv hais txog formability thiab weldability?
430 muaj ductility zoo heev thiab tuaj yeem nkag tau tob tob, khoov, thiab spun, ua rau nws zoo tagnrho rau qhov tsim. Txawm li cas los xij, nws qhov weldability yog qhov ncaj ncees rau cov neeg pluag rau cov ntawv thov tseem ceeb. Raws li qib ferritic tsis ruaj khov, vuam tuaj yeem ua rau cov qoob loo loj hlob nyob rau hauv tshav kub- cuam tshuam cheeb tsam, ua rau brittleness thiab txo corrosion kuj. Rau cov uas tsis yog- cov welds tseem ceeb, cov txheej txheem tsim nyog nrog cov khoom siv hluav taws xob tsawg yog xav tau. Rau qhov tseem ceeb welded sib dhos, qib ferritic ruaj khov zoo li 439 lossis lwm tsev neeg ntawm cov hlau yuav tsum raug txiav txim siab.

Vim li cas 430 feem ntau yog tus nqi ntau tshaj - xaiv stainless hlau zoo rau cov haujlwm tshwj xeeb?
Nws tus nqi -kev ua tau zoo yog los ntawm ob yam tseem ceeb: qhov tsis muaj npib tsib xee kim thiab nws cov ntim ntau lawm. Rau cov ntawv thov uas nws cov kev txwv tsis pub muaj kev txhawj xeeb -xws li cov khoom siv sab hauv qhuav, cov khoom siv nrog cov txheej tiv thaiv, lossis cov khoom uas muaj lub neej ua haujlwm luv luv -430 muab cov txiaj ntsig zoo nkauj thiab txaus corrosion tsis kam ntawm stainless hlau ntawm tus nqi qis tshaj. Qhov no ua rau nws yog qhov kev xaiv tsim nyog rau tus nqi- cov qauv tsim muaj txiaj ntsig qhov twg qib austenitic yuav raug qhia ntau dhau.

Dab tsi yog cov lus qhia kawg uas tus tsim qauv yuav tsum ua raws thaum qhia txog 430 stainless hlau?
Txhawm rau siv 430 ua tiav, txwv tsis pub nws daim ntawv thov kom qhuav lossis ntub dej tsis tu ncua, tsis yog - chloride ib puag ncig. Tsis txhob qhia nws rau cov qauv welded uas yuav ntsib kev pabcuam corrosive, rau qhov chaw hauv kev sib cuag nrog cov khoom noj acids lossis dej ntsev, lossis rau sab nrauv architecture hauv cov pa phem lossis cov ntug dej hiav txwv. Rau cov xwm txheej zoo li no, xav txog kev hloov pauv mus rau 304, 316, lossis cov qib ferritic ruaj khov zoo li 439. Nco ntsoov xyuas kom meej qhov chaw tiav (xws li 2B, BA, txhuam) tau teev kom ua tau raws li qhov xav tau ntawm kev zoo nkauj, vim nws qhov tsos yog qhov tseem ceeb ntawm kev muag khoom.