Hastelloy N (N10003) Hastelloy
Hastelloy N alloy yog nickel-based high-temperature alloy khoom siv nyob rau hauv molten ntsev reactors. Nws muaj kev tiv thaiv corrosion zoo heev, tsis kam rau cov hluav taws xob neutron thiab cov khoom siv hluav taws xob kub zoo.
Txawm li cas los xij, lub reactor qhov hluav taws xob kub tau mus txog 750 degree, tshaj qhov tso cai kub ntawm Hastelloy N alloy ntawm 704 degree, uas txhais tau hais tias cov hlau tsis tuaj yeem ua haujlwm ruaj khov hauv 750 degree molten ntsev ib puag ncig ntev. Yog li ntawd, nws yog ib qho tsim nyog yuav tsum tau ua kom zoo dua Hastelloy N alloy kom tau raws li qhov yuav tsum tau muaj ntawm cov kub kub molten ntsev reactors.
Txij li thaum Mn lub ntsiab lus muaj qhov zoo ntawm stabilizing austenite thiab txhim kho oxidation kuj nyob rau hauv high-temperature alloys, tsab xov xwm no yuav siv Hastelloy N alloy raws li kev tshawb fawb lub hom phiaj. Los ntawm kev tsim thiab npaj Hastelloy N alloys nrog sib txawv Mn txheem, thiab siv optical microscope (OM) thiab scanning Lub zog ntawm Mn cov ntsiab lus ntawm microstructure, mechanical zog thiab oxidation zog ntawm HastelloyN alloy tau kawm siv cov kev sim tshuaj ntsuam xyuas xws li electron microscope (SEM + EDS + EBSD), universal tensile tshuab, X-ray diffractometer (XRD) thiab electron sojntsuam (EPMA). . Cov txiaj ntsig tshawb fawb hauv qab no tau txais:
(1) Qhov sib ntxiv ntawm Mn ntsiab tuaj yeem txhawb kev ua kom zoo ntawm Hastelly N alloy nplej, nce tus naj npawb ntawm cov carbides sib cais, thiab cov carbides maj mam condense rau hauv cov blocks thiab cov saw ntev, thiab sib sau ua ke ntawm cov ciam teb.
(2) Thaum ncab ntawm chav tsev kub, lub zog tensile ntawm 0.5Mn alloy tsis zoo. Thaum Mn cov ntsiab lus siab dua 1wt%, lub zog tensile tau txhim kho. Dimples thiab step-zoo li textures tshwm rau ntawm pob txha tawg. Txoj kev tawg yog tsim los ntawm cleavage cracking thiab resistant cracking. Qhov sib tov tawg. Thaum ncab ntawm qhov kub ntawm 850 degree, Mn tsis muaj kev cuam tshuam rau lub zog tensile ntawm cov hlau. Lubricant siv lead ua dav hlau tshwm rau ntawm qhov chaw tawg, thiab txoj kev tawg yog intergranular brittle cracking.
(3) Raws li cov ntsiab lus Mn nce, cov khoom antioxidant ntawm cov hlau zoo tuaj. Ntawm 700 degree, 1wt% Mn cov ntsiab lus alloy muaj qhov zoo tshaj plaws oxidation tsis kam, thiab oxidation tus nqi yog 25.9% qis dua li ntawm 0Mn alloy. Ntawm 850 degree, 0.75wt% Mn cov ntsiab lus alloy muaj qhov zoo tshaj plaws oxidation tsis kam, thiab oxidation tus nqi yog 52.1% qis dua li ntawm 0Mn alloy.
(4) oxide zaj duab xis muaj txheej txheej txheej. Tom qab oxidation ntawm 700 degree /200h, oxide zaj duab xis ntawm tag nrho cov alloys muab faib ua ob txheej. Cov txheej txheej sab nrauv yog NiO, Fe2O3 thiab lwm yam oxides, thiab txheej sab hauv yog Cr2O3, MoOz thiab NiMn2O4 thiab lwm yam oxides. Qhov saum npoo ntawm cov hlau tsis muaj qhov pom tseeb poob, thiab NiO txheej tsis zoo thiab ntom. Raws li Mn cov ntsiab lus nce, oxide txheej ntawm cov hlau maj mam ua thinner. Tom qab oxidation ntawm 850 degree / 100h, oxide zaj duab xis ntawm ib tug alloy nrog ib tug Mn ntsiab lus ntawm 0 ~ 0.2wt% muab faib ua peb txheej. Cov txheej txheej yog feem ntau NiO, nruab nrab txheej yog NiO, NiMn2O4 thiab lwm yam oxides sib xyaw, thiab txheej sab hauv yog Cr2O3, MoO2 thiab lwm yam oxides. Khoom siv; Rau cov alloys nrog Mn ntsiab lus ntawm 0 ~ 0.2wt%, oxide zaj duab xis muab faib ua ob txheej, txheej txheej yog NiO thiab ib qho me me ntawm NiFeO4, NiMn2O4, thiab txheej sab hauv yog Cr2O3, MoO2 thiab lwm yam oxides. Raws li Mn cov ntsiab lus nce, qhov tshwm sim oxidation sab hauv ntawm cov hlau maj mam tsis muaj zog.
(5) Qhov sib ntxiv ntawm Mn tuaj yeem txhawb kev tsim ntawm NiMn2O4 spinel tiv thaiv txheej ntawm NiO thiab matrix, tiv thaiv kev nkag mus ntawm lub ntiaj teb sab nraud thiab sab nraud diffusion ntawm alloying ntsiab lus, thiab txhim kho cov kev ua haujlwm ntawm cov hlau nplaum.
Hastelloy N muaj kev tiv thaiv zoo heev rau thermal fluoride ntsev oxidation ntawm 704-871 degree, thiab muaj peev xwm antioxidant zoo heev hauv huab cua. Nws muaj kev tiv thaiv zoo rau kev laus thiab embrittlement, thiab muaj kev ua haujlwm zoo.
Siv: Molten fluoride ntsev thawv
