Qhov duality ntawm carbon hauv stainless hlau

Cov pa roj carbon yog ib qho ntawm cov khoom tseem ceeb ntawm cov hlau lag luam. Kev ua tau zoo thiab cov qauv ntawm cov hlau feem ntau yog txiav txim siab los ntawm cov ntsiab lus thiab kev faib tawm ntawm cov pa roj carbon hauv cov hlau. Cov nyhuv ntawm cov pa roj carbon yog qhov tseem ceeb tshwj xeeb hauv cov hlau tsis xeb. Kev cuam tshuam ntawm cov pa roj carbon rau cov qauv ntawm cov hlau tsis xeb feem ntau yog pom tseeb hauv ob qho tib si. Ntawm ib sab tes, cov pa roj carbon yog ib qho khoom uas ruaj khov austenite, thiab cov nyhuv yog loj (kwv yees li 30 npaug ntawm cov nickel), ntawm qhov tod tes, vim muaj kev sib raug zoo ntawm cov pa roj carbon thiab chromium. Loj, nrog chromium - ib qho series ntawm carbides. Yog li ntawd, hais txog lub zog thiab kev tiv thaiv corrosion, lub luag haujlwm ntawm cov pa roj carbon hauv cov hlau tsis xeb yog qhov tsis sib xws.

Kev lees paub txoj cai ntawm qhov kev cuam tshuam no, peb tuaj yeem xaiv cov hlau tsis xeb nrog cov ntsiab lus carbon sib txawv raws li kev siv sib txawv.
Piv txwv li, cov ntsiab lus chromium txheem ntawm tsib qib hlau ntawm 0Crl3 ~ 4Cr13, uas yog qhov siv dav tshaj plaws hauv kev lag luam thiab tsawg tshaj plaws, tau teeb tsa ntawm 12 ~ 14%, uas yog, cov yam ntxwv uas carbon thiab chromium tsim chromium carbide raug coj mus rau hauv tus account. Lub hom phiaj txiav txim siab yog tias tom qab carbon thiab chromium raug sib xyaw ua ke rau hauv chromium carbide, cov ntsiab lus chromium hauv cov tshuaj khov yuav tsis qis dua cov ntsiab lus chromium tsawg kawg nkaus ntawm 11.7%.

Raws li tsib qib hlau no, vim muaj qhov sib txawv ntawm cov pa roj carbon, lub zog thiab kev tiv thaiv corrosion kuj sib txawv. Qhov kev tiv thaiv corrosion ntawm 0Cr13 ~ 2Crl3 hlau zoo dua tab sis lub zog qis dua li ntawm 3Crl3 thiab 4Cr13 hlau. Nws feem ntau yog siv rau kev tsim cov khoom siv.
Vim muaj cov pa roj carbon ntau, ob hom hlau no muaj zog heev thiab feem ntau siv rau kev tsim cov caij nplooj ntoos hlav, riam thiab lwm yam khoom uas xav tau lub zog siab thiab hnav tsis kam. Piv txwv li, txhawm rau kov yeej qhov corrosion intergranular ntawm 18-8 chromium-nickel stainless hlau, cov pa roj carbon ntawm cov hlau tuaj yeem txo qis dua 0.03%, lossis ib qho khoom (titanium lossis niobium) uas muaj kev sib raug zoo dua li chromium thiab carbon tuaj yeem ntxiv los tiv thaiv nws los ntawm kev tsim carbide. Piv txwv li, Chromium, thaum qhov nyuaj siab thiab hnav tsis kam yog qhov yuav tsum tau ua tseem ceeb, peb tuaj yeem nce cov pa roj carbon ntawm cov hlau thaum nce cov pa roj chromium kom haum, kom ua tau raws li qhov yuav tsum tau ua ntawm qhov nyuaj thiab hnav tsis kam, thiab coj mus rau hauv tus account qee qhov kev tiv thaiv corrosion, kev siv hauv kev lag luam ua cov kabmob, cov cuab yeej ntsuas thiab cov hniav nrog cov hlau stainless 9Cr18 thiab 9Cr17MoVCo, txawm hais tias cov pa roj carbon siab txog li 0.85 ~ 0.95%, vim tias lawv cov pa roj chromium kuj nce raws li, yog li nws tseem lav qhov corrosion tsis kam. Yuav tsum tau.

Feem ntau hais lus, cov pa roj carbon ntawm cov hlau stainless uas siv tam sim no hauv kev lag luam yog qhov tsawg heev. Feem ntau ntawm cov hlau stainless muaj cov pa roj carbon ntawm 0.1 txog 0.4%, thiab cov hlau uas tiv taus kua qaub muaj cov pa roj carbon ntawm 0.1 txog 0.2%. Cov hlau stainless uas muaj cov pa roj carbon ntau dua 0.4% tsuas yog ib feem me me ntawm tag nrho cov qib, vim tias nyob rau hauv feem ntau cov xwm txheej ntawm kev siv, cov hlau stainless ib txwm muaj kev tiv thaiv corrosion ua lawv lub hom phiaj tseem ceeb. Tsis tas li ntawd, cov pa roj carbon qis dua kuj yog vim qee qhov kev xav tau ntawm cov txheej txheem, xws li kev vuam yooj yim thiab kev hloov pauv txias.