Qhov kuvsN690 hlauua los ntawm thiab ua li cas nws yog tsim?
N690 yog ib lub siab -carbon, siab-chromium stainless hlau los ntawm Böhler-Uddeholm uas siv cobalt thiab molybdenum los txhawb hardness, ntug tuav, thiab corrosion kuj thaum nyob twj ywm txaus rau hard- siv thiab kev cai riam.
Böhler thawj zaug qhia N690 nyob rau xyoo 1990s raws li kev hloov pauv ntawm nws cov kev phais- qib 440B alloy. Lub hom phiaj yog yooj yim: tsim ib lub stainless uas yuav harden yav dhau los 60 HRC, tuav ib tug ntug ntev tshaj 440C, tsis tau zom thiab polish yooj yim txaus rau ntau lawm tooling. Chemically, N690 hovers around1.07% carbon, 17% chromium, 1.1% molybdenum, 1.5% cobalt, 0.4% manganese, thiab 0.40% silicon. Cov cobalt ua raws li cov txheej txheem thib ob hardening, zawm cov martensitic lattice kom carbides faib ntau yam sib npaug. Molybdenum thiab chromium ua haujlwm ua ke los tiv thaiv pitting nyob rau hauv ib puag ncig ntsev, ua rau N690 nrov nrog European dhia dej- riam tuam txhab xws li Extrema Ratio thiab LionSteel. Ob xyoo dhau los no cov qauv tseem nyob ruaj khov, uas piav qhia txog vim li cas cov ntaub ntawv los ntawm 2003 thiab 2025 nyeem yuav luag zoo ib yam. Qhov kev txuas ntxiv no tau cia cov cua sov- cov kws kho mob kho lub sijhawm-kub nkhaus kom txog rau thaum lawv tuaj yeem nyem txhua qhov kawg ntawm qhov nyuaj yam tsis muaj kev cuam tshuam.
N690 steel ua li cas niaj hnub no?
Kev lag luam N690 yog melted nyob rau hauv hluav taws xob arc rauv, refined nrog Argon-Oxygen Decarburization (AOD), thiab feem ntau muab ib tug Electroslag Remelting (ESR) dhau los txhim kho kev huv thiab toughness.
Niaj hnub nimno N690 pib raws li cov khoom seem thiab alloying them rau hauv 100-tuj EAF. Tom qab pib melting, lub ladle hloov cov cua sov mus rau lub nkoj AOD qhov twg leej faj thiab cov pa roj carbon ntau dhau tau tshuab tawm. Tom ntej no los ESR: qeeb remelt los ntawm ib tug conductive slag da dej uas lim tawm oxides thiab sulfides, ua rau ib tug billet nrog tsawg inclusions thiab txo nyob rau hauv anisotropy. Lub ingot tau kub-forged thiab dov rau hauv cov khoom lag luam ntawm 3 hli mus rau 12 hli tuab. Qee lub mills ntxiv lub tshuab nqus tsev kub-kho anneal los muab cov neeg tsim riam ib yam 240 HB mob uas cov tshuab tau yooj yim tsis tau tawm tsam warping hauv kev thauj mus los.
