Stainless hlau yog feem ntau muab faib rau martensitic hlau, ferritic steel, austenitic hlau thiab li on. Tsis tas li ntawd, nws yuav muab faib ua chromium stainless hlau, chrome nickel stainless hlau, chromium manganese nitrogen stainless hlau thiab li on.
Ferritic stainless hlau: chromium muaj 12% ~ 30%. Nws kev tsis sib haum xeeb, toughness thiab weldability nce nrog nce ntawm chromium cov ntsiab lus, thiab chloride tsis ua hauj lwm zoo dua lwm hom stainless hlau.
Qhov cim rau pawg no yog Crl7, Cr17Mo2Ti, Cr25, Cr25Mo3Ti, Cr28 thiab hais txog. Ferritic stainless hlau muaj corrosion kuj zoo thiab antioxidant zog vim nws cov chromium cov ntsiab lus, tab sis neeg pluag txhua yam thiab cov khoom siv zog. Nws yog siv nyob rau hauv acid acid qauv thiab siv los ua antioxidant hlau. Qhov hom hlau no tiv tau qhov corrosion ntawm cua, nitric acid thiab saline kua, thiab muaj cov yam ntxwv ntawm cov pa kub oxidation thiab tsis tshua muaj coefficient ntawm thermal expansion. Nws yog siv hauv cov khoom siv nitric acid thiab cov khoom noj khoom haus, thiab tseem tuaj yeem ua cov khoom ua haujlwm siab, xws li cov roj cav turbine thiab lwm yam.
Austenitic stainless hlau: chromium yog ntau tshaj 18%, kuj muaj txog 8% ntawm xee thiab ib qho me me ntawm molybdenum, titanium, nitrogen thiab lwm yam. Nws muaj kev qhia zoo thiab muaj peev xwm ntxeem tau ntau yam kev nruab nrab ntawm qhov nruab nrab.
Cov nquag siv cov austenitic steel hlau yog 1Cr18Ni9 thiab 0Cr19Ni9. 0Cr19Ni9 steel wC <0.08%, hlau="" tooj="" cim=""> Qhov no hom hlau muaj ntau Ni thiab Cr, uas ua rau cov hlau austenite ntawm chav tsev kub. Qhov no hom hlau muaj cov yas zoo, muaj zog, muaj kev sib tshuam thiab kev txhuam tsis muaj corrosion. Nws muaj kev txhim kho corrosion hauv oxidizing thiab reductive medium. Nws yog siv los ua cov khoom siv acid resistant, xws li cov thawv rau corrosion resistant thiab khoom hauv ob sab phlu, kav dej, thiab nitric acid resistant khoom. Austenitic stainless hlau feem ntau yog kho los ntawm cov kua tshuaj. Cov hlau yuav tsum rhuab mus rau 1050 ~ 1150 degrees thiab tom qab ntawd txias kom tau txais ib theem austenite.
Austenitic ferrite duplex stainless hlau muaj qhov zoo ntawm ob lub austenitic thiab ferritic stainless steels, thiab muaj superplasticity.
Austenite thiab ferrite tshwm sim txog ib nrab ntawm cov hlau tsis huv. Yog tias cov ntsiab lus tsis tshua muaj C, Cov ntsiab lus Cr yog 18% ~ 28% thiab Ni cov ntsiab lus yog 3% ~ 10%. Ib co steels kuj muaj Mo, Cu, Si, Nb, Ti, N thiab lwm yam kev txua hlau. Qhov no hom hlau muaj cov yam ntxwv ntawm austenite thiab ferritic stainless hlau. Piv nrog ferrite, nws muaj ntau dua cov yas, toughness, tsis muaj qhov sov sov brittleness, intergranular corrosion kuj thiab vuam kev kawm. Nyob rau tib lub sijhawm, lub brittleness ntawm ferritic stainless hlau ntawm 475 C, high thermal conductivity thiab superplasticity kuj khaws cia. Muab piv rau cov hlau steel hlau tsis muaj hlau, lub zog muaj siab, thiab intergranular corrosion thiab chloride stress corrosion kuj ua tau zoo tuaj. Duplex stainless hlau muaj zoo pitting corrosion kuj thiab kuj yog ib tug nickel txuag stainless hlau.
Martensitic hlau tsis muaj hlau: siab zog, tab sis pluag tsis zoo thiab weldability.
Lub hom brandensitic stainless hlau yog 1Cr13, 3Cr13 thiab hais txog. Vim tias nws cov ntsiab lus siab, nws muaj zog, nyuaj thiab hnav tsis kam, tab sis qhov kev xeb ntawm qhov corrosion yog pluag. Qee qhov chaw, xws li caij nplooj ntoos hlav, cav ntoo, hydraulic xovxwm valve, yog siv rau cov khoom kho siab thiab corrosion kuj. Cov hom hlau no siv tom qab quenching thiab tempering.
