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Chitsulo chosapanga dzimbiri chomwe chimagwiritsidwa ntchito kwambiri komanso mitundu yake yopangidwayo imagonjetsedwa ndi dzimbiri m'malo ozungulira chifukwa cha passivation layer yomwe ili ndi chromium oxide.Zimbiri ndi kukokoloka kwa zitsulo pachikhalidwe kugwirizana ndi chiwonongeko cha zigawo izi, koma kawirikawiri pa mlingo tosaoneka, malingana ndi chiyambi cha pamwamba inhomogeneity.Mu ntchito iyi, nanoscale pamwamba mankhwala heterogeneity kuzindikiridwa ndi spectroscopic microscopy ndi chemometric kusanthula mosayembekezereka imayang'anira kuwola ndi dzimbiri ozizira adagulung'undisa cerium kusinthidwa super duplex zosapanga dzimbiri zitsulo 2507 (SDSS) pa kutentha kutentha khalidwe khalidwe.mbali ina.Ngakhale X-ray photoelectron maikulosikopu anasonyeza yunifolomu Kuphunzira za chilengedwe wosanjikiza Cr2O3, ozizira adagulung'undisa SDSS anasonyeza zotsatira passigation chifukwa cha kugawa m'dera Fe3+ olemera nanoislands pa Fe/Cr okusayidi wosanjikiza.Kudziwa kumeneku pamlingo wa atomiki kumapereka kumvetsetsa kwakuya kwa chitsulo chosapanga dzimbiri ndipo kumayembekezeredwa kuthandiza kuthana ndi dzimbiri zazitsulo zofananira za aloyi.
Chiyambireni kupangidwa kwa chitsulo chosapanga dzimbiri, kukana kwa dzimbiri kwa ma aloyi a ferrochromium akuti kumabwera chifukwa cha chromium, yomwe imapanga okusayidi/oxyhydroxide yamphamvu yowonetsa machitidwe osasunthika m'malo ambiri.Poyerekeza ndi zitsulo zosapanga dzimbiri (austenitic ndi ferritic), super duplex zosapanga dzimbiri (SDSS) zokhala ndi kukana kwa dzimbiri zili ndi zida zapamwamba zamakina1,2,3.Kuwonjezeka kwa mphamvu zamakina kumapangitsa kuti pakhale mapangidwe opepuka komanso ophatikizika.Mosiyana ndi izi, SDSS yazachuma imakana kwambiri kukumba ndi kuwonongeka kwa ming'alu, zomwe zimapangitsa moyo wautali wautumiki komanso kugwiritsa ntchito mokulirapo pakuwongolera kuipitsidwa, zotengera zamankhwala, komanso mafakitale amafuta ndi gasi akunyanja4.Komabe, mitundu yopapatiza ya kutentha kwa kutentha ndi kusawoneka bwino zimalepheretsa kugwiritsa ntchito kwake kwakukulu.Chifukwa chake, SDSS yasinthidwa kuti ipititse patsogolo zinthu zomwe zili pamwambapa.Mwachitsanzo, kusinthidwa kwa Ce ndi kuwonjezera kwakukulu kwa N 6, 7, 8 kunayambitsidwa mu 2507 SDSS (Ce-2507).Kuphatikizika koyenera kwa 0.08 wt.% rare earth element (Ce) kumakhala ndi phindu pamakina a DSS, chifukwa kumakulitsa kuwongolera kwambewu ndi mphamvu zamalire ambewu.Kukana kuvala ndi dzimbiri, kulimba kwamphamvu komanso kulimba kwa zokolola, komanso kugwira ntchito kotentha kwasinthidwanso9.Nayitrogeni wambiri amatha kulowa m'malo mwa nickel yamtengo wapatali, zomwe zimapangitsa SDSS kukhala yotsika mtengo10.
Posachedwapa, SDSS yakhala yopunduka pa kutentha kosiyanasiyana (kutentha kochepa, kuzizira ndi kutentha) kuti ikwaniritse bwino makina6,7,8.Komabe, kukana kwa dzimbiri kwabwino kwa SDSS kumachitika chifukwa cha kukhalapo kwa filimu yopyapyala ya oxide pamtunda, yomwe imakhudzidwa ndi zinthu zambiri, monga kukhalapo kwa magawo ambiri okhala ndi malire osiyanasiyana ambewu, kutsika kosafunikira komanso machitidwe osiyanasiyana.mkati inhomogeneous microstructure zosiyanasiyana austenitic ndi ferritic magawo ndi olumala 7 .Chifukwa chake, kuphunzira kwa microdomain katundu wamafilimu oterowo pamlingo wamagetsi ndikofunikira kwambiri kuti timvetsetse kuwonongeka kwa SDSS ndipo kumafunikira njira zoyesera zovuta.Mpaka pano, njira zowonongeka pamwamba monga Auger electron spectroscopy11 ndi X-ray photoelectron spectroscopy12,13,14,15 komanso makina olimba a X-ray photoelectron photoelectron amasiyanitsa, koma nthawi zambiri amalephera kupatukana, zigawo za mankhwala za chinthu chomwecho m'malo osiyanasiyana mumlengalenga pa nanoscale.Kafukufuku wambiri waposachedwa wagwirizanitsa makutidwe ndi okosijeni a m'deralo a chromium ndi khalidwe la corrosion la 17 austenitic stainless steels, 18 martensitic stainless steels, ndi SDSS 19, 20. Komabe, maphunzirowa ayang'ana kwambiri zotsatira za Cr heterogeneity (mwachitsanzo, Cr3 + state resistance) pa kukana kwa okosijeni.Lateral heterogeneity mu makutidwe ndi okosijeni amati zinthu zimatha chifukwa chamitundu yosiyanasiyana yokhala ndi zinthu zofanana, monga ma oxide achitsulo.Mankhwalawa amatenga kakulidwe kakang'ono ka thermomechanically pafupi ndi mzake, koma amasiyana muzolemba ndi makutidwe ndi okosijeni state16,21.Choncho, kuwulula chiwonongeko cha okusayidi mafilimu ndiye dzenje kumafuna kumvetsa pamwamba inhomogeneity pa tinthu ting'onoting'ono mlingo.Ngakhale izi ndizofunikira, kuwunika kwachulukidwe monga lateral oxidation heterogeneity, makamaka chitsulo pamlingo wa nano / atomiki, akadali akusowa ndipo kufunikira kwawo pakukana kwa dzimbiri sikudziwika.Mpaka posachedwapa, chikhalidwe cha mankhwala a zinthu zosiyanasiyana, monga Fe ndi Ca, quantitatively anafotokoza pa zitsanzo zitsulo ntchito zofewa X-ray photoelectron microscopy (X-PEEM) mu nanoscale synchrotron ma radiation maofesi.Kuphatikizidwa ndi njira za X-ray absorption spectroscopy (XAS), X-PEEM imathandizira muyeso wa XAS wokhala ndi mawonekedwe apamwamba komanso owoneka bwino, opereka chidziwitso chamankhwala okhudzana ndi kapangidwe kake ndi kapangidwe kake kakemidwe kachidziwitso ka malo mpaka nanometer sikelo 23.Kuyang'ana kowoneka bwino kumeneku kwa malo oyambira pansi pa maikulosikopu kumathandizira kuyesa kwamankhwala am'deralo ndipo kumatha kuwonetsa kusintha kwamankhwala komwe sikunazindikiridwe kale mu Fe layer.
Kafukufukuyu amakulitsa ubwino wa PEEM pozindikira kusiyana kwa mankhwala pa nanoscale ndipo akupereka njira yowunikira pamwamba pa atomiki kuti amvetsetse khalidwe la corrosion la Ce-2507.Amagwiritsa ntchito data ya K-means cluster chemometric data24 kupanga mapu amitundu yonse yamankhwala (heterogeneity) yazinthu zomwe zikukhudzidwa, ndi mawonekedwe awo amankhwala omwe amawonetsedwa poyimira ziwerengero.Mosiyana ndi dzimbiri wamba chifukwa cha kuwonongeka kwa filimu ya chromium oxide, kusayenda bwino kwaposachedwa komanso kusakhazikika kwa dzimbiri kumachitika chifukwa cha Fe3+ rich nanoislands pafupi ndi Fe/Cr oxide layer, yomwe ingakhale kuukira kwa oxide oxide.Imapanga filimu pamalo ake ndipo imayambitsa dzimbiri.
Makhalidwe oyipa a SDSS 2507 opunduka adawunikidwa koyamba pogwiritsa ntchito miyeso ya electrochemical.Pa mkuyu.Chithunzi 1 chikuwonetsa ma curve a Nyquist ndi Bode a zitsanzo zosankhidwa mu acidic (pH = 1) njira zamadzimadzi za FeCl3 kutentha kwa firiji.Ma electrolyte osankhidwa amakhala ngati oxidizing amphamvu, omwe akuwonetsa chizolowezi cha filimu ya passivation kuti iwonongeke.Ngakhale kuti zinthuzo sizinakhazikike mokhazikika kutentha kwa chipinda, kusanthula uku kunapereka chidziwitso pazochitika zomwe zingalephereke komanso njira zowonongeka pambuyo pa dzimbiri.Dera lofanana (mkuyu 1d) linagwiritsidwa ntchito kuti ligwirizane ndi mawonedwe a electrochemical impedance spectroscopy (EIS), ndipo zotsatira zofananira zofananira zikuwonetsedwa mu Table 1. Mabwalo osakwanira theka adawonekera poyesa zitsanzo zomwe zimagwiritsidwa ntchito ndi zotentha zogwiritsidwa ntchito, pamene mabwalo ogwirizana omwe amakakamizidwa ndi theka anali ozizira (mkuyu 1b).Mu mawonekedwe a EIS, ma semicircle radius amatha kuonedwa ngati kukana polarization (Rp) 25,26.Rp yankho lomwe limathandizidwa ndi SDSS mu Table 1 lili pafupi 135 kΩ cm-2, komabe kwa SDSS yotentha komanso yozizira, timatha kuwona zotsika kwambiri za 34.7 ndi 2.1 kΩ cm-2 motsatana.Kutsika kwakukulu kumeneku kwa Rp kukuwonetsa kuwononga kwa mapindidwe a pulasitiki pakuyenda komanso kukana dzimbiri, monga tawonera m'malipoti am'mbuyomu 27, 28, 29, 30.
a Nyquist, b, c Bode impedance ndi mawonekedwe a gawo, ndi chitsanzo chofanana cha dera la d, kumene RS ndi kukana kwa electrolyte, Rp ndi polarization resistance, ndipo QCPE ndi gawo lokhazikika la element oxide lomwe limagwiritsidwa ntchito pofanizira mphamvu yosayenerera (n) .Miyezo ya EIS idachitika popanda katundu.
Zosintha zoyambirira zimawonetsedwa pazithunzi za Bode ndipo malo okwera pafupipafupi amayimira kukana kwa electrolyte RS26.Pamene mafupipafupi amachepetsa, kusokoneza kumawonjezeka ndipo mbali yolakwika imapezeka, kusonyeza kulamulira kwa capacitance.The gawo ngodya ukuwonjezeka, kusunga ake pazipita pazipita osiyanasiyana osiyanasiyana pafupipafupi, ndiyeno amachepetsa (mkuyu. 1c).Komabe, muzochitika zonse zitatu izi mtengo wapamwamba udakali wochepera 90 °, kusonyeza khalidwe losavomerezeka la capacitive chifukwa cha kubalalitsidwa kwa capacitive.Choncho, QCPE nthawi zonse gawo element (CPE) ntchito kuimira interfacial capacitance kugawa anachokera pamwamba roughness kapena inhomogeneity, makamaka mawu a atomiki scale, fractal geometry, electrode porosity, sanali yunifolomu kuthekera, ndi pamwamba kudalira kugawa panopa.Electrode geometry31,32.CPE impedance:
pomwe j ndi nambala yongoyerekeza ndipo ω ndi ma frequency aang'ono.QCPE ndi ma frequency odziyimira pawokha nthawi zonse molingana ndi malo otseguka a electrolyte.n ndi nambala yamphamvu yopanda malire yomwe imalongosola kupatuka kuchokera ku khalidwe labwino la capacitor la capacitor, mwachitsanzo, pafupi n ndi 1, CPE yapafupi ndi mphamvu yoyera, ndipo ngati n ili pafupi ndi ziro, ndiko kukana.Kupatuka kwakung'ono kwa n, pafupi ndi 1, kukuwonetsa kusachita bwino kwapadziko lapansi pambuyo poyesa polarization.QCPE ya SDSS yoziziritsa yozizira ndiyokwera kwambiri kuposa zinthu zofanana, zomwe zikutanthauza kuti mawonekedwe apamwamba ndi ocheperako.
Mogwirizana ndi zitsulo zosapanga dzimbiri zosapanga dzimbiri zosapanga dzimbiri, ma Cr okwera kwambiri a SDSS nthawi zambiri amabweretsa kukana kwa dzimbiri kwa SDSS chifukwa cha kukhalapo kwa filimu yoteteza oxide pamtunda17.Filimu yodutsayi nthawi zambiri imakhala yolemera mu Cr3+ oxides ndi/kapena hydroxides, makamaka kuphatikiza Fe2+, Fe3+ oxides ndi/kapena (oxy)hydroxides 33.Ngakhale mawonekedwe ofanana pamwamba, passivating okusayidi wosanjikiza, ndipo palibe kuwonongeka koonekera pamwamba, monga kutsimikiziridwa ndi zithunzi zazing'ono,6,7 khalidwe dzimbiri la SDSS yotentha-yogwira ntchito ndi ozizira adagulung'undisa ndi osiyana choncho amafuna kuphunzira mozama za deformation microstructure ndi structural khalidwe la chitsulo.
Microstructure ya chitsulo chosapanga dzimbiri chopunduka chinafufuzidwa mochulukira pogwiritsa ntchito ma X-ray amkati ndi synchrotron amphamvu kwambiri (Zithunzi Zowonjezera 1, 2).Kusanthula mwatsatanetsatane kwaperekedwa mu Supplementary Information.Ngakhale kuti makamaka zimagwirizana ndi mtundu wa gawo lalikulu, kusiyana kwa magawo a gawo la voliyumu kumapezeka, zomwe zalembedwa mu Supplementary Table 1. Kusiyana kumeneku kungagwirizane ndi magawo a inhomogeneous gawo pamtunda, komanso magawo a magawo a volumetric omwe amachitidwa mozama mosiyanasiyana.kuzindikira ndi X-ray diffraction.(XRD) yokhala ndi magwero osiyanasiyana amphamvu amafotoni ochitika.Kuchulukirachulukira kwa austenite m'zitsanzo zoziziritsa kuzizira, zotsimikiziridwa ndi XRD kuchokera ku labotale, zikuwonetsa kutsika kwabwinoko komanso kukana dzimbiri bwino35, pomwe zolondola komanso zowerengera zimawonetsa mikhalidwe yosiyana mu magawo agawo.Kuonjezera apo, kukana kwa dzimbiri kwachitsulo kumadaliranso kuchuluka kwa kukonzanso kwambewu, kuchepetsa kukula kwa tirigu, kuwonjezeka kwa microdeformations ndi kusasunthika kwa dislocation komwe kumachitika panthawi ya chithandizo cha thermomechanical36,37,38.Zitsanzo zogwiritsidwa ntchito zotentha zimasonyeza chikhalidwe chochuluka, chosonyeza kuti mbewu za micron-size, pamene mphete zosalala zomwe zimawonedwa muzitsulo zozizira (Supplementary Fig. 3) zimasonyeza kukonzanso kwakukulu kwambewu ku nanoscale mu ntchito yapitayi6, yomwe iyenera kuthandizira kuti filimu iwonongeke.kupanga ndi kuwonjezeka kwa kukana dzimbiri.Kachulukidwe kachulukidwe kameneka kamakhala kogwirizana ndi kutsika kochepa kwa pitting, komwe kumagwirizana bwino ndi kuyeza kwa electrochemical.
Zosintha m'magawo amankhwala a ma microdomain azinthu zoyambira zidaphunziridwa mwadongosolo pogwiritsa ntchito X-PEEM.Ngakhale kuchuluka kwa zinthu alloying, Cr, Fe, Ni ndi Ce39 anasankhidwa pano, popeza Cr ndi chinthu chofunika kwambiri pakupanga filimu passivation, Fe ndiye chinthu chachikulu mu zitsulo, ndi Ni kumawonjezera passivation ndi miyeso dongosolo ferrite-austenitic gawo ndi cholinga cha Ce kusinthidwa.Posintha mphamvu ya ma radiation ya synchrotron, RAS idakutidwa kuchokera pamwamba ndi zinthu zazikulu za Cr (m'mphepete L2.3), Fe (m'mphepete L2.3), Ni (m'mphepete L2.3) ndi Ce (m'mphepete M4.5).kutentha kupanga ndi kuzizira kugudubuza Ce-2507 SDSS.Kusanthula koyenera kwa data kunachitika pophatikiza kuwongolera mphamvu ndi data yofalitsidwa (monga XAS 40, 41 pa Fe L2, 3 m'mphepete).
Pa mkuyu.Chithunzi 2 chikuwonetsa zithunzi za X-PEEM zogwiritsidwa ntchito zotentha (mkuyu 2a) ndi ozizira (mkuyu 2d) Ce-2507 SDSS ndi XAS m'mphepete mwa Cr ndi Fe L2,3 pazigawo zodziwika payekha.Mphepete mwa L2,3 ya XAS imafufuza madera osagwiritsidwa ntchito a 3d pambuyo pa electron photoexcitation pa ma spin-orbit splitting levels 2p3/2 (L3 m'mphepete) ndi 2p1/2 (L2 m'mphepete).Zambiri zokhudza valence state ya Cr zinapezedwa kuchokera ku XAS pa L2,3 m'mphepete mwa Chithunzi 2b, e.Kuyerekeza ndi oweruza.42,43 adawonetsa kuti nsonga zinayi zidawonedwa pafupi ndi m'mphepete mwa L3, zotchedwa A (578.3 eV), B (579.5 eV), C (580.4 eV) ndi D (582.2 eV), zowonetsera octahedral Cr3+, yogwirizana ndi Cr2O3 ion.Mawonekedwe oyesera amavomerezana ndi ziwerengero zamaganizo zomwe zikuwonetsedwa mu mapanelo a b ndi e, omwe amapezeka kuchokera ku mawerengedwe angapo a kristalo pa mawonekedwe a Cr L2.3 pogwiritsa ntchito crystal field ya 2.0 eV44.Mawonekedwe onse a SDSS yogwira ntchito yotentha komanso ozizira amakutidwa ndi wosanjikiza wofanana wa Cr2O3.
chithunzi chotenthetsera cha X-PEEM cha SDSS chopunduka chofanana ndi b Cr L2.3 m'mphepete ndi c Fe L2.3 m'mphepete, d X-PEEM chifaniziro chotentha cha SDSS chozizira chogwirizana ndi e Cr L2.3 m'mphepete ndi f Fe L2 .3 m'mphepete mwa mbali ( f).Mawonekedwe a XAS amajambulidwa pamalo osiyanasiyana olembedwa pazithunzi zotentha (a, d), mizere ya madontho alalanje mu (b) ndi (e) imayimira mawonekedwe oyeserera a XAS a Cr3+ okhala ndi mtengo wa crystal field 2.0 eV.Pazithunzi za X-PEEM, gwiritsani ntchito phale lotenthetsera kuti chithunzicho chizitha kumveka bwino, pomwe mitundu yochokera ku buluu kupita ku yofiyira imakhala yolingana ndi mphamvu ya mayamwidwe a X-ray (kuchokera pansi mpaka pamwamba).
Mosasamala kanthu za chilengedwe cha mankhwala azinthu zachitsulo izi, chikhalidwe cha mankhwala cha zowonjezera za Ni ndi Ce alloying element pa zitsanzo zonsezi sizinasinthe.Zojambula zowonjezera.Zithunzi 5-9 zikuwonetsa zithunzi za X-PEEM ndi mawonekedwe ofananira a XAS a Ni ndi Ce pamalo osiyanasiyana pazithunzi zogwira ntchito zotentha komanso zozizira.Ni XAS ikuwonetsa makutidwe ndi okosijeni a Ni2+ pamtunda wonse woyezedwa wa zitsanzo zotentha komanso zozizira (Zokambirana Zowonjezera).Tiyenera kukumbukira kuti, pankhani ya zitsanzo zotentha, chizindikiro cha XAS cha Ce sichinawonedwe, pamene pazitsanzo zozizira zozizira, mawonekedwe a Ce3 + adawonedwa.Kuwona kwa mawanga a Ce mu zitsanzo zozizira kunawonetsa kuti Ce makamaka imawonekera mu mawonekedwe a precipitates.
Mu SDSS yopunduka ya thermally, palibe kusintha kwapangidwe kwa XAS pa Fe L2,3 m'mphepete komwe kunawonedwa (mkuyu 2c).Komabe, Fe matrix yaying'ono-regionally imasintha mankhwala ake pazigawo zisanu ndi ziwiri zosankhidwa mwachisawawa za SDSS yozizira, monga momwe tawonetsera mkuyu 2f.Kuonjezera apo, kuti mupeze lingaliro lolondola la kusintha kwa dziko la Fe pa malo osankhidwa mumkuyu 2f, maphunziro apamtunda adachitidwa (mkuyu 3 ndi Supplementary Fig. 10) momwe zigawo zing'onozing'ono zozungulira zinasankhidwa.Mawonekedwe a XAS a Fe L2,3 m'mphepete mwa machitidwe a α-Fe2O3 ndi Fe2 + octahedral oxides adapangidwa ndi mawerengedwe angapo a crystal field pogwiritsa ntchito crystal fields 1.0 (Fe2 +) ndi 1.0 (Fe3 +)44. Tikuwona kuti α-Fe2O3 ndi γ-Fe2O3 ali ndi ma symmetries osiyanasiyana am'deralo45,46, Fe3O4 ali ndi kuphatikiza kwa Fe2+ & Fe3+,47, ndi FeO45 monga divalent Fe2+ oxide (3d6). Tikuwona kuti α-Fe2O3 ndi γ-Fe2O3 ali ndi ma symmetries osiyanasiyana am'deralo45,46, Fe3O4 ali ndi kuphatikiza kwa Fe2+ & Fe3+,47, ndi FeO45 monga divalent Fe2+ oxide (3d6).Dziwani kuti α-Fe2O3 ndi γ-Fe2O3 ali ndi ma symmetries osiyanasiyana amderalo45,46, Fe3O4 amaphatikiza onse Fe2+ ndi Fe3+,47 ndi FeO45 mu mawonekedwe a divalent okusayidi Fe2+ (3d6).Dziwani kuti α-Fe2O3 ndi γ-Fe2O3 ali ndi ma symmetries osiyanasiyana amderalo45,46, Fe3O4 ali ndi kuphatikiza kwa Fe2+ ndi Fe3+,47 ndi FeO45 imagwira ntchito ngati divalent Fe2+ oxide (3d6).Ma ion onse a Fe3+ mu α-Fe2O3 ali ndi maudindo okha a Oh, pamene γ-Fe2O3 nthawi zambiri amaimiridwa ndi Fe3+ t2g [Fe3+5/3V1/3] mwachitsanzo O4 spinel yokhala ndi malo mwachitsanzo maudindo.Chifukwa chake, ma ion a Fe3+ mu γ-Fe2O3 ali ndi malo onse a Td ndi Oh.Monga tafotokozera mu pepala lapitalo, 45 ngakhale kuti chiwerengero cha mphamvu za awiriwa ndi chosiyana, chiŵerengero chawo champhamvu mwachitsanzo / t2g ndi ≈1, pamene pakali pano chiwerengero cha kuwonetsetsa kwakukulu mwachitsanzo / t2g ndi pafupifupi 1. Izi sizikuphatikizanso kuti zomwe zikuchitika panopa ndi Fe3 + yokha.Poganizira za Fe3O4 ndi Fe2+ ndi Fe3+, chinthu choyamba chomwe chimadziwika kuti chili ndi malire (olimba) L3 m'mphepete mwa Fe chimasonyeza chigawo chaching'ono (chachikulu) chosagwiritsidwa ntchito t2g.Izi zikugwiranso ntchito ku Fe2 + (Fe3 +), zomwe zikuwonetsa kuti gawo loyamba la kuwonjezereka likuwonetsa kuwonjezeka kwa zomwe zili mu Fe2 + 47.Zotsatirazi zikuwonetsa kuti kukhalapo kwa Fe2 + ndi γ-Fe2O3, α-Fe2O3 ndi / kapena Fe3O4 kumalamulira pamtunda wozizira wamagulu.
Zithunzi zowonjezera za photoelectron zotentha za mawonekedwe a XAS (a, c) ndi (b, d) akuwoloka m'mphepete mwa Fe L2,3 m'malo osiyanasiyana m'madera osankhidwa 2 ndi E mu Fig.2d.
Deta yoyesera yopezedwa (mkuyu 4a ndi Supplementary Fig. 11) imakonzedwa ndikufananizidwa ndi deta ya mankhwala oyeretsera 40, 41, 48. Mitundu itatu yosiyana ya experimentally anaona Fe L-edge XAS spectra (XAS- 1, XAS-2 ndi XAS-3: Mkuyu 4a).Makamaka, mawonekedwe a 2-a (otchulidwa ngati XAS-1) mu Fig. 3b yotsatiridwa ndi spectrum 2-b (yotchedwa XAS-2) inawonedwa pa malo onse ozindikira, pamene mawonekedwe ngati E-3 ankawoneka mu chithunzi 3d (chotchedwa XAS-3) chinawonedwa pa malo enieni.Monga lamulo, magawo anayi adagwiritsidwa ntchito kuti azindikire maiko omwe alipo mu chitsanzo chomwe chikuphunziridwa: (1) mawonekedwe a spectral L3 ndi L2, (2) malo amphamvu a makhalidwe L3 ndi L2, (3) kusiyana kwa mphamvu L3-L2., (4) L2/L3 kuchuluka kwamphamvu.Malinga ndi zowonera (mkuyu 4a), zigawo zonse zitatu za Fe, zomwe ndi Fe0, Fe2 +, ndi Fe3 +, zilipo pa SDSS pamwamba pa phunziro.Chiŵerengero champhamvu chowerengera L2/L3 chinasonyezanso kukhalapo kwa zigawo zonse zitatu.
mawonekedwe a XAS a Fe okhala ndi data yoyeserera yosiyana (mizere yolimba XAS-1, XAS-2 ndi XAS-3 imagwirizana ndi 2-a, 2-b ndi E-3 mumkuyu 2 ndi 3) Kuyerekeza, Octahedron Fe2+, Fe3+ yokhala ndi kristalo kumunda wamtengo wapatali wa 1.0 eV, V1, XAS-5, data-XAS, motsatana. 2, XAS-3) ndi data yofananira ya LCF (mzere wakuda wokhazikika), komanso mawonekedwe a XAS-3 okhala ndi Fe3O4 (mkhalidwe wosakanikirana wa Fe) ndi Fe2O3 (woyera Fe3+).
Kuphatikizika kwa mzere (LCF) wamiyezo itatu 40, 41, 48 idagwiritsidwa ntchito kuwerengera kuchuluka kwa iron oxide.LCF inakhazikitsidwa pazithunzi zitatu zosankhidwa za Fe L-edge XAS zosonyeza kusiyana kwakukulu, zomwe ndi XAS-1, XAS-2 ndi XAS-3, monga momwe tawonetsera mkuyu 4b-d.Pazoyika za LCF, 10% Fe0 idaganiziridwa muzochitika zonse chifukwa chakuti tidawona gawo laling'ono mu data yonse, komanso chifukwa chakuti chitsulo chachitsulo ndi gawo lalikulu lachitsulo. Zowonadi, kuya kwa kuyezetsa kwa X-PEEM kwa Fe (~ 6 nm) 49 ndikokulirapo kuposa makulidwe a oxidation layer (pang'ono> 4 nm), kulola kudziwika kwa chizindikiro kuchokera kuchitsulo chachitsulo (Fe0) pansi pa gawo la passivation. Zowonadi, kuya kwa kuyezetsa kwa X-PEEM kwa Fe (~ 6 nm) 49 ndikokulirapo kuposa makulidwe a oxidation layer (pang'ono> 4 nm), kulola kudziwika kwa chizindikiro kuchokera kuchitsulo chachitsulo (Fe0) pansi pa gawo la passivation. Действительно, пробная глубина X-PEEM для Fe (~ 6 нм)49 больше, чем предполагаемая толщина слоя окисления (немного > 4 mphindi), ndikupeza железной матрицы (Fe0) ndi пассивирующим слоем. Zoonadi, kafukufuku wa X-PEEM kuya kwa Fe (~ 6 nm) 49 ndi wamkulu kuposa makulidwe omwe amaganiziridwa kuti ndi oxidation wosanjikiza (pang'ono> 4 nm), zomwe zimapangitsa kuti zizindikire chizindikiro kuchokera kuchitsulo chachitsulo (Fe0) pansi pa passivation wosanjikiza.事实上， X-PEEM 对Fe（~6 nm）49的检测深度大于估计的氧化层厚度（略> 4 nm） （Fe0）的信号.事实上 , X-PEEM 对 Fe (~ 6 nm) 49 的 检测 深度 大于 的 氧化层 厚度 略 略> 4 nm） 允杀铁基体 (fe0) 的。 信号 信号 信号 信号Фактически, глубина обнаружения Fe (~ 6 нм) 49 с помощью X-PEEM больше, чем предполагаемая толщина оксидного слоя (немного > 4 он нал от железной матрицы (Fe0) ниже пассивирующего слоя. Ndipotu, kuya kwa kuzindikira kwa Fe (~ 6 nm) 49 ndi X-PEEM ndi yaikulu kuposa makulidwe omwe amayembekezeredwa a oxide wosanjikiza (pang'ono> 4 nm), zomwe zimathandiza kuzindikira chizindikiro kuchokera kuchitsulo chachitsulo (Fe0) pansi pa gawo la passivation. .Kuphatikizika kosiyanasiyana kwa Fe2+ ndi Fe3+ kunachitidwa kuti apeze njira yabwino kwambiri yothetsera deta yoyeserera.Pa mkuyu.4b ikuwonetsa mawonekedwe a XAS-1 ophatikiza Fe2+ ndi Fe3+, pomwe kuchuluka kwa Fe2+ ndi Fe3+ kunali kofanana ndi pafupifupi 45%, kuwonetsa mayiko osakanikirana a Fe.Pomwe pamawonekedwe a XAS-2, kuchuluka kwa Fe2+ ndi Fe3+ kumakhala ~ 30% ndi 60%, motsatana.Fe2+ ​​ndi yochepa kuposa Fe3+.Chiŵerengero cha Fe2 + ku Fe3, chofanana ndi 1: 2, chimatanthauza kuti Fe3O4 ikhoza kupangidwa mofanana pakati pa Fe ions.Kuphatikiza apo, pamawonekedwe a XAS-3, kuchuluka kwa Fe2+ ndi Fe3+ kumakhala ~ 10% ndi 80%, zomwe zikuwonetsa kutembenuka kwakukulu kwa Fe2+ kupita ku Fe3+.Monga tafotokozera pamwambapa, Fe3 + ikhoza kubwera kuchokera ku α-Fe2O3, γ-Fe2O3 kapena Fe3O4.Kuti mumvetsetse gwero lalikulu la Fe3 +, mawonekedwe a XAS-3 adakonzedwa ndi miyezo yosiyana ya Fe3 + mu Chithunzi 4e, kusonyeza kufanana ndi miyezo yonseyi poganizira za B.Komabe, mphamvu ya nsonga zamapewa (A: kuchokera ku Fe2 +) ndi chiwerengero cha B/A champhamvu chimasonyeza kuti mawonekedwe a XAS-3 ali pafupi, koma sagwirizana ndi mawonekedwe a γ-Fe2O3.Poyerekeza ndi kuchuluka kwa γ-Fe2O3, Fe 2p XAS nsonga ya A SDSS ili ndi mphamvu yowonjezera pang'ono (mkuyu 4e), yomwe imasonyeza mphamvu yapamwamba ya Fe2 +.Ngakhale kuti mawonekedwe a XAS-3 ndi ofanana ndi a γ-Fe2O3, kumene Fe3 + ilipo pa maudindo a Oh ndi Td, kuzindikiritsa madera osiyanasiyana a valence ndi kugwirizana kokha pamphepete mwa L2,3 kapena L2 / L3 kuchuluka kwamphamvu kumakhalabe nkhani ya kafukufuku wopitilira.kukambirana chifukwa cha zovuta za zinthu zosiyanasiyana zomwe zimakhudza mawonekedwe omaliza41.
Kuphatikiza pa kusiyana kwa mawonekedwe a mankhwala a madera osankhidwa omwe atchulidwa pamwambapa, kusiyanasiyana kwa mankhwala padziko lonse a zinthu zofunika kwambiri Cr ndi Fe kunayesedwanso mwa kuyika mawonedwe onse a XAS omwe amapezeka pachitsanzo pogwiritsa ntchito njira ya K-means clustering.Mbiri ya Cr L m'mphepete imapanga magulu awiri omwe amagawika bwino m'zitsanzo zotentha komanso zoziziritsa kuzizira zomwe zikuwonetsedwa mu Mkuyu.5. Ndizodziwikiratu kuti palibe kusintha kwapangidwe komwe kumawonedwa ngati kofanana, popeza ma centroids awiri a XAS Cr spectra akufanana.Mawonekedwe owoneka bwino amagulu awiriwa ali pafupifupi ofanana ndi omwe amafanana ndi Cr2O342, zomwe zikutanthauza kuti zigawo za Cr2O3 ndizosiyana molingana ndi SDSS.
Cr L K-amatanthauza masango a m'mphepete, ndipo b ndiye ma XAS centroids ofanana.Zotsatira za K-njira X-PEEM kuyerekeza kwa SDSS yozizira: c Cr L2.3 m'mphepete mwa masango a K-amatanthauza masango ndi d ofanana ndi XAS centroids.
Kuti tiwonetse mapu a m'mphepete mwa FeL ovuta kwambiri, magulu anayi ndi asanu okonzedwa bwino ndi ma centroids ogwirizana nawo (mawonekedwe a spectral) adagwiritsidwa ntchito pazithunzi zotentha komanso zozizira, motsatira.Choncho, peresenti (%) ya Fe2 + ndi Fe3 + ingapezeke mwa kugwirizana ndi LCF yomwe ikuwonetsedwa mu Fig.4.pseudoelectrode kuthekera kwa Epseudo ngati ntchito ya Fe0 idagwiritsidwa ntchito kuwulula microchemical inhomogeneity ya filimu ya okusayidi pamwamba.Epseudo akuyerekezedwa ndi lamulo losakanikirana,
kumene \(\rm{E}_{\rm{Fe}/\rm{Fe}^{2 + (3 + )}}\) ndi \(\rm{Fe} + 2e^ – \ ku \rm { Fe}^{2 + (3 + )}\), 0.440 ndi 0.036 V, motsatana.Madera omwe ali ndi mphamvu zochepa amakhala ndi zowonjezera za Fe3 +.The angathe kugawa mu thermally opunduka zitsanzo ali wosanjikiza khalidwe ndi pazipita kusintha pafupifupi 0,119 V (mkuyu 6a, b).Kugawa kothekera kumeneku kumagwirizana kwambiri ndi mawonekedwe apamwamba (mkuyu 6a).Palibe kusintha kwina komwe kumadalira malo omwe ali mkati mwa laminar omwe adawonedwa (mkuyu 6b).M'malo mwake, chifukwa kugwirizana kwa oxides osiyana ndi nkhani zosiyanasiyana Fe2+ ndi Fe3+ ozizira adagulung'undisa SDSS, munthu akhoza kuona sanali yunifolomu chikhalidwe cha pseudopotential (mkuyu. 6c, d).Ma Fe3+ oxides ndi/kapena (oxy) hydroxides ndizomwe zimapanga dzimbiri muzitsulo ndipo zimatha kulowa mpweya ndi madzi50.Pachifukwa ichi, zilumba zolemera mu Fe3 + zimaonedwa kuti ndizogawidwa m'deralo ndipo zikhoza kuonedwa ngati madera owonongeka.Panthawi imodzimodziyo, gradient mu gawo lomwe lingatheke, m'malo mwa mtengo wokwanira wa zomwe zingatheke, zingagwiritsidwe ntchito ngati chizindikiro cha malo omwe akuwonongeka.Kugawa kosagwirizana kumeneku kwa Fe2 + ndi Fe3 + pamwamba pa SDSS yotsekedwa kuzizira kungasinthe makina am'deralo ndikupereka malo ogwira ntchito pamtunda panthawi ya kuwonongeka kwa filimu ya okusayidi ndi zochitika zowonongeka, zomwe zimalola kuti matrix azitsulo apitirize kuwononga, zomwe zimapangitsa kuti mkati mwawo mukhale heterogeneity.katundu ndi kuchepetsa zoteteza katundu wa passivating wosanjikiza.
K-amatanthauza masango ndi ma XAS centroids mu Fe L2.3 m'mphepete mwa dera la X-PEEM ac ndi df ya SDSS yozizira.a, d K-amatanthauza ziwembu zamagulu zokutidwa pazithunzi za X-PEEM.Mphamvu yowerengera ya pseudoelectrode (Epseudo) imatchulidwa pamodzi ndi chiwembu chamagulu a K-njira.Kuwala kwa chithunzi cha X-PEEM, monga mtundu wa mkuyu.
Pafupifupi yunifolomu ya Cr koma mawonekedwe osiyanasiyana amankhwala a Fe amatsogolera ku kuwonongeka kwa filimu ya oxide ndi dzimbiri mu Ce-2507 yotentha komanso yozizira.Katunduyu wa Ce-2507 wozizira waphunziridwa bwino.Pankhani ya mapangidwe oxides ndi hydroxides Fe mu mpweya wozungulira mu ntchito pafupifupi ndale, zotsatira zake ndi motere:
Zomwe zili pamwambazi zimachitika muzochitika zotsatirazi kutengera kusanthula kwa X-PEEM.Phewa laling'ono lolingana ndi Fe0 limalumikizidwa ndi chitsulo chachitsulo chapansi.Kachitidwe kachitsulo ka Fe ndi chilengedwe kumapangitsa kupanga Fe(OH)2 wosanjikiza (equation (5)), yomwe imakulitsa chizindikiro cha Fe2+ mu Fe L-edge XAS.Kuwonekera kwa mpweya kwa nthawi yaitali kungapangitse kupanga Fe3O4 ndi / kapena Fe2O3 oxides pambuyo pa Fe (OH) 252,53.Mitundu iwiri yokhazikika ya Fe, Fe3O4 ndi Fe2O3, ikhozanso kupanga mu Cr3 + wolemera wotetezera wosanjikiza, umene Fe3O4 imakonda mawonekedwe a yunifolomu ndi omata.Kukhalapo kwa zonsezi kumabweretsa ma oxidation states (XAS-1 spectrum).Mawonekedwe a XAS-2 makamaka amafanana ndi Fe3O4.Pomwe kuyang'ana kwa mawonekedwe a XAS-3 m'malo angapo adawonetsa kutembenuka kwathunthu kukhala γ-Fe2O3.Popeza kuzama kwa ma X-ray opangidwa ndi pafupifupi 50 nm, chizindikiro chochokera kumunsi chapansi chimapangitsa kuti pakhale mphamvu yapamwamba ya A pachimake.
Mawonekedwe a XPA akuwonetsa kuti gawo la Fe mufilimu ya oxide ili ndi mawonekedwe osanjikiza ophatikizidwa ndi Cr oxide wosanjikiza.Mosiyana ndi zizindikiro za passivation chifukwa m'deralo inhomogeneity wa Cr2O3 pa dzimbiri, ngakhale yunifolomu wosanjikiza Cr2O3 ntchito imeneyi, otsika dzimbiri kukana amaona mu nkhani iyi, makamaka ozizira adagulung'undisa toyesa.Khalidwe lowonedwa limatha kumveka ngati kusiyanasiyana kwa chikhalidwe cha okosijeni chamankhwala pamtunda wapamwamba (Fe), womwe umakhudza magwiridwe antchito a dzimbiri.Chifukwa stoichiometry yemweyo wa chapamwamba wosanjikiza (chitsulo okusayidi) ndi m'munsi wosanjikiza (chromium okusayidi) 52,53 bwino mogwirizana (kumatira) pakati pawo kumabweretsa kuyenda pang'onopang'ono zitsulo kapena ayoni mpweya mu latisi, amenenso, kumabweretsa kuwonjezeka kukana dzimbiri.Choncho, chiŵerengero chosalekeza cha stoichiometric, mwachitsanzo, mkhalidwe umodzi wa okosijeni wa Fe, ndibwino kusiyana ndi kusintha kwadzidzidzi kwa stoichiometric.SDSS yopunduka kutentha imakhala ndi mawonekedwe ofananirako, malo oteteza kwambiri, komanso kukana kwa dzimbiri bwino.Ngakhale kwa SDSS yozizira, kupezeka kwa zilumba zolemera za Fe3 + pansi pa chitetezero kumaphwanya umphumphu wa pamwamba ndipo kumayambitsa galvanic corrosion ndi gawo lapansi lapafupi, lomwe limabweretsa kugwa kwakukulu kwa Rp (Table 1).Mawonekedwe a EIS ndi kukana kwake kwa dzimbiri kumachepetsedwa.Zitha kuwoneka kuti kugawidwa kwanuko kwa zilumba zolemera za Fe3 + chifukwa cha kupunduka kwa pulasitiki kumakhudza kwambiri kukana kwa dzimbiri, zomwe ndi zopambana pa ntchitoyi.Chifukwa chake, kafukufukuyu akuwonetsa zithunzi zowoneka bwino za kuchepa kwa kukana kwa dzimbiri kwa zitsanzo za SDSS zophunziridwa ndi njira yopunthira pulasitiki.
Kuphatikiza apo, ngakhale kuti kutulutsa kwapadziko lapansi kosowa m'zitsulo zapawiri kumawonetsa kugwira ntchito bwino, kuyanjana kwa chinthu chowonjezera ichi ndi matrix achitsulo pamtundu wa dzimbiri malinga ndi mawonekedwe a spectroscopic microscopy sikuli kovuta.Mawonekedwe a ma sigino a Ce (kudzera m'mphepete mwa XAS M) amangowoneka m'malo ochepa panthawi yozizira, koma amasokonekera panthawi yotentha ya SDSS, kuwonetsa mvula yam'deralo ya Ce muzitsulo zachitsulo, m'malo mophatikizana.Ngakhale kuti sizikuwongolera kwambiri makina a SDSS6,7, kukhalapo kwa zinthu zosawerengeka zapadziko lapansi kumachepetsa kukula kwa zophatikizika ndipo zimaganiziridwa kuti zimalepheretsa kupindika m'chigawo choyambirira54.
Pomaliza, ntchitoyi ikuwonetsa zotsatira za kusiyanasiyana kwapadziko lapansi pakuwonongeka kwa 2507 SDSS yosinthidwa ndi cerium powerengera kuchuluka kwa mankhwala omwe ali ndi zida za nanoscale.Timayankha funso chifukwa chomwe chitsulo chosapanga dzimbiri chimawononga ngakhale pansi pa chitsulo choteteza oxide powerengera ma microstructure ake, chemistry yake, komanso kukonza ma siginecha pogwiritsa ntchito K-njira masango.Zatsimikiziridwa kuti zilumba zolemera kwambiri mu Fe3 +, kuphatikizapo kugwirizana kwawo kwa octahedral ndi tetrahedral pamodzi ndi Fe2 +/Fe3+ yosakanikirana, ndizo zomwe zimawononga ndi kuwononga filimu ya SDSS yozizira.Nanoislands yolamulidwa ndi Fe3 + imatsogolera kukana kwa dzimbiri kosakwanira ngakhale pakakhala gawo lokwanira la stoichiometric Cr2O3 passivating layer.Kuphatikiza pa kupita patsogolo kwa methodological pakuzindikira momwe nanoscale chemical heterogeneity pa dzimbiri, ntchito yopitilira ikuyembekezeka kulimbikitsa njira zaumisiri kuti zithandizire kukana kwa dzimbiri zazitsulo zosapanga dzimbiri panthawi yopanga zitsulo.
Kukonzekera Ce-2507 SDSS ingot ntchito mu phunziro ili, zosakaniza zosakaniza kuphatikizapo Fe-Ce master aloyi losindikizidwa ndi chubu chitsulo koyera anasungunuka mu 150 makilogalamu sing'anga ng'anjo kulowetsedwa pafupipafupi kupanga chitsulo chosungunula ndi kutsanulira mu nkhungu.Zolemba zamakemikolo zoyezedwa (wt%) zalembedwa mu Supplementary Table 2. Ingots zimayamba kutenthedwa kukhala midadada.Kenaka adatsekedwa pa 1050 ° C kwa mphindi 60 kuti apeze zitsulo mumkhalidwe wokhazikika, ndiyeno amazimitsidwa m'madzi kutentha.Zitsanzo zophunziridwazo zidaphunziridwa mwatsatanetsatane pogwiritsa ntchito TEM ndi DOE kuphunzira magawo, kukula kwambewu ndi morphology.Zambiri zokhudzana ndi zitsanzo ndi njira zopangira zitha kupezeka muzinthu zina6,7.
Zitsanzo za Cylindrical (φ10 mm × 15 mm) za kukanikiza kotentha zinakonzedwa kuti olamulira a silinda anali ofanana ndi njira yopindika ya chipika.Kutentha kwapamwamba kwambiri kunkachitika pa kutentha kosiyanasiyana kwa 1000-1150 ° C pogwiritsa ntchito Gleeble-3800 simulator yotentha pamtundu wa 0.01-10 s-1.Pamaso mapindikidwe, zitsanzo anatenthedwa pa mlingo wa 10 °C s-1 kwa 2 min pa kutentha anasankha kuthetsa kutentha gradient.Pambuyo pokwaniritsa kutentha, chitsanzocho chinapunduka kukhala mtengo weniweni wa 0.7.Pambuyo popindika, zitsanzozo zinazimitsidwa nthawi yomweyo ndi madzi kuti zisunge mawonekedwe opunduka.Chitsanzo chowumitsidwacho chimadulidwa mofanana ndi njira yoponderezedwa.Pa kafukufukuyu, tidasankha chitsanzo chokhala ndi vuto lotentha la 1050 ° C, 10 s-1 chifukwa kulimba kwapang'ono komwe kumawonedwa kunali kokwezeka kuposa zitsanzo zina7.
Zitsanzo zazikulu (80 × 10 × 17 mm3) za njira yolimba ya Ce-2507 zidagwiritsidwa ntchito mu mphero ya LG-300 ya magawo atatu asynchronous two roll yokhala ndi makina abwino kwambiri pakati pa magawo ena onse opunduka6.Mlingo wa kupsinjika ndi kuchepetsa makulidwe panjira iliyonse ndi 0.2 m·s-1 ndi 5%, motsatana.
Makina opangira ma electrochemical a Autolab PGSTAT128N adagwiritsidwa ntchito poyezera ma elekitiromu a SDSS pambuyo pozizira kwambiri mpaka 90% kuchepetsa makulidwe (1.0 ofanana ndi strain yeniyeni) komanso pambuyo pa kukanikiza kotentha pa 1050 ° C kwa 10 s-1 mpaka kupsinjika kwenikweni kwa 0.7.Malo ogwirira ntchito ali ndi ma elekitirodi atatu okhala ndi ma electrode a saturated calomel monga ma elekitirodi owerengera, ma graphite counter electrode, ndi chitsanzo cha SDSS ngati electrode yogwira ntchito.Zitsanzozo zidadulidwa kukhala masilindala okhala ndi mainchesi 11.3 mm, mbali zomwe mawaya amkuwa adagulitsidwa.Zitsanzozo zidakhazikitsidwa ndi epoxy, ndikusiya malo otseguka a 1 cm2 ngati ma elekitirodi ogwirira ntchito (mbali yapansi pa chitsanzo cha cylindrical).Samalani pakuchiritsa epoxy ndi mchenga wotsatira ndikupukuta kuti mupewe kusweka.Malo ogwirira ntchito anali pansi ndikupukutidwa ndi kuyimitsidwa kwa diamondi ndi kukula kwa 1 μm, kutsukidwa ndi madzi osungunuka ndi ethanol, ndikuwumitsa mu mpweya wozizira.Asanayezedwe ndi electrochemical, zitsanzo zopukutidwa zidawululidwa ndi mpweya kwa masiku angapo kuti apange filimu yachilengedwe ya okusayidi.Njira yothetsera madzi ya FeCl3 (6.0 wt%), yokhazikika ku pH = 1.0 ± 0.01 ndi HCl molingana ndi malingaliro a ASTM, imagwiritsidwa ntchito kufulumizitsa dzimbiri zitsulo zosapanga dzimbiri55 chifukwa zimawononga pamaso pa ma chloride ion okhala ndi oxidizing amphamvu komanso otsika pH8 Miyezo Yachilengedwe.Miwiritsani chitsanzo mu njira yoyesera kwa ola limodzi kuti chifike pafupi ndi malo osasunthika musanapange miyeso iliyonse.Kwa zitsanzo zolimba, zotentha, komanso zozizira, miyeso ya impedance inkachitika pazidziwitso zotseguka (OPC) za 0.39, 0.33, ndi 0.25 V, motero, pamafupipafupi kuchokera ku 1 105 mpaka 0.1 Hz ndi matalikidwe a 5 mV.Mayesero onse a mankhwala adabwerezedwa nthawi zosachepera 3 pamikhalidwe yofanana kuti atsimikizire kubwezeredwa kwa data.
Pamiyezo ya HE-SXRD, zitsulo za rectangular duplex zoyezera 1 × 1 × 1.5 mm3 zidayezedwa kuti zitsimikizire kuchuluka kwa gawo la mtengo wa Brockhouse high-energy wiggler ku CLS, Canada56.Kusonkhanitsa deta kunachitika mu Debye-Scherrer geometry kapena kufalitsa geometry kutentha firiji.X-ray wavelength yoyendetsedwa ndi calibrator ya LaB6 ndi 0.212561 Å, yomwe imafanana ndi 58 keV, yomwe ili yokwera kwambiri kuposa ya Cu Kα (8 keV) yomwe imagwiritsidwa ntchito kwambiri ngati magwero a X-ray a labotale.Chitsanzocho chinali pamtunda wa 740 mm kuchokera ku detector.Kuchuluka kwachidziwitso cha chitsanzo chilichonse ndi 0.2 × 0.3 × 1.5 mm3, chomwe chimatsimikiziridwa ndi kukula kwa mtengo ndi makulidwe a chitsanzo.Deta yonse inasonkhanitsidwa pogwiritsa ntchito chojambulira cha dera la Perkin Elmer, chojambulira chathyathyathya cha X-ray, ma pixel 200 µm, 40 × 40 cm2 pogwiritsa ntchito nthawi yowonekera ya 0.3 s ndi mafelemu 120.
Miyezo ya X-PEEM ya machitidwe awiri osankhidwa adachitidwa pa Beamline MAXPEEM PEEM kumapeto kwa labotale ya MAX IV (Lund, Sweden).Zitsanzo zinakonzedwa mofanana ndi miyeso ya electrochemical.Zitsanzo zokonzedwazo zinasungidwa mumlengalenga kwa masiku angapo ndikuchotsedwa mu chipinda cha ultrahigh vacuum musanayambe kuyatsidwa ndi synchrotron photons.Kusintha kwa mphamvu kwa mzere wamtengowo kunapezedwa poyesa kuchuluka kwa zokolola za ion m'dera lachisangalalo kuchokera ku N 1 s kufika ku 1 \ (\pi _g^ \st\) pafupi ndi hv = 401 eV mu N2 ndi kudalira mphamvu ya photon pa E3/2 , 57. Chifupikitso choyezera mawonekedwe a 0. Choncho, kusintha kwa mphamvu ya beamline kunali E/∆E = 700 eV/0.3 eV> 2000 ndi flux ≈1012 ph/s pogwiritsa ntchito monochromator yosinthidwa ya SX-700 yokhala ndi Si 1200-line mm−1 grating ya Fe 2p, L3, L2, L2, Edge2, Cr3, L2, Edge 2, Edge2 ndi Ce M4,5 m'mphepete. Choncho, kusintha kwa mphamvu ya beamline kunali E/∆E = 700 eV/0.3 eV> 2000 ndi flux ≈1012 ph/s pogwiritsa ntchito SX-700 monochromator yosinthidwa yokhala ndi Si 1200-line mm−1 grating ya Fe 2p, L3pdge, L2.3pdge, L2. ndi Ce M4.5 m'mphepete. Таким образом, энергетическое разрешение канала пучка было оценено как E/∆E = 700 эВ/0,3 эВ > 2000 ndi поток ≈1012 fotokopi нохроматора SX-700 с решеткой Si 1200 штрихов/мм для Fe кромка 2p L2,3, кромка Cr 2p L2,3, кромка Ni 2p L2,3 ndi кромка Ce M4,5. Choncho, kusintha kwa mphamvu kwa njira yamtengo wapatali kunayesedwa ngati E / ∆E = 700 eV / 0.3 eV> 2000 ndi flux ≈1012 f / s pogwiritsa ntchito SX-700 monochromator yosinthidwa ndi Si grating ya 1200 mizere / mm kwa Fe edge 2p L2, 3, CEP edge L2, 3, CEP edge M2 ndi L2 edge. 4.5.因此，光束线能量分辨率估计為E/ΔE = 700 eV/0.3 eV > 2000 和通量≈1012 ph/s，通过的使用带有1Si 120mm -700 单色器用于Fe 2p L2,3 边缘、Cr 2p L2,3 边缘、Ni 2p L2,3 边缘和Ce M4,5 边缘.因此 , 光束线 能量 分辨率 為 為 為 δe = 700 EV/0.3 EV> 2000 和 ≈1012 PH/S , 使用带有 带有 12 mm . SX-700 单色器 于 于 用 用用Fe 2p L2.3 边缘、Cr 2p L2.3 边缘、Ni 2p L2.3 边缘和Ce M4.5 边缘.Choncho, pamene ntchito kusinthidwa SX-700 monochromator ndi 1200 mzere Si grating.3, Cr edge 2p L2.3, Ni m'mphepete 2p L2.3 ndi Ce m'mphepete M4.5.Jambulani mphamvu ya photon mu masitepe 0.2 eV.Pa mphamvu iliyonse, zithunzi za PEEM zidajambulidwa pogwiritsa ntchito chowunikira cha CMOS cha TVIPS F-216 chokhala ndi ma bin 2 x 2, chomwe chimakhala ndi ma pixel a 1024 × 1024 pagawo la 20 µm.Nthawi yowonetsera zithunzizo inali 0.2 s, pafupifupi mafelemu 16.Mphamvu ya chithunzi cha photoelectron imasankhidwa m'njira yoti ipereke chizindikiro chachikulu cha electron.Miyezo yonse inkachitika mwanthawi zonse pogwiritsa ntchito mtengo wa photon wokhala ndi polarized.Zambiri zokhudzana ndi miyeso zitha kupezeka mu kafukufuku wakale.Pambuyo pophunzira njira yodziwira kuchuluka kwa ma elekitironi (TEY) ndikugwiritsa ntchito mu X-PEEM49, kuya kwa kuyesa kwa njirayi kuyerekezedwa kukhala pafupifupi 4-5 nm kwa chizindikiro cha Cr ndi pafupifupi 6 nm kwa Fe.Kuzama kwa Cr kuli pafupi kwambiri ndi makulidwe a filimu ya oxide (~ 4 nm) 60,61 pomwe kuya kwa Fe ndikokulirapo kuposa makulidwe.XRD yosonkhanitsidwa m'mphepete mwa Fe L ndi chisakanizo cha XRD cha iron oxides ndi Fe0 kuchokera ku matrix.Poyamba, mphamvu ya ma elekitironi otulutsidwa imachokera ku mitundu yonse ya ma elekitironi yomwe imathandizira ku TEY.Komabe, chizindikiro chachitsulo choyera chimafuna mphamvu zapamwamba za kinetic kuti ma elekitironi adutse pamtunda wa oxide kupita pamwamba ndikusonkhanitsidwa ndi analyzer.Pankhaniyi, chizindikiro cha Fe0 makamaka chifukwa cha ma elekitironi a LVV Auger, komanso ma elekitironi achiwiri omwe amatulutsidwa ndi iwo.Kuphatikiza apo, mphamvu ya TEY yothandizidwa ndi ma elekitironi amawola panthawi yothawa ma elekitironi, ndikuchepetsanso kuyankha kwa Fe0 pamapu achitsulo a XAS.
Kuphatikizira migodi ya data mu cube data (X-PEEM data) ndi gawo lofunikira pakuchotsa zidziwitso zofunikira (zamankhwala kapena zakuthupi) munjira zambiri.Kuphatikizika kwa K-njira kumagwiritsidwa ntchito kwambiri m'magawo angapo, kuphatikiza masomphenya a makina, kukonza zithunzi, kuzindikira mosayang'aniridwa, luntha lochita kupanga, komanso kusanthula kwamagulu.Mwachitsanzo, K-njira clustering yachita bwino pakuphatikiza deta yazithunzi za hyperspectral.M'malo mwake, pazambiri zambiri, ma algorithm a K-anthu amatha kuwagawa mosavuta potengera zomwe ali nazo (photon energy properties).K-kutanthauza clustering ndi njira yobwerezabwereza yogawa deta m'magulu a K osadutsana (magulu), pomwe pixel iliyonse imakhala ya gulu linalake kutengera kufalikira kwa malo a inhomogeneity ya mankhwala muzitsulo za microstructural.K-njira aligorivimu imaphatikizapo magawo awiri: mu gawo loyamba, ma centroids a K amawerengedwa, ndipo gawo lachiwiri, mfundo iliyonse imapatsidwa masango okhala ndi ma centroid oyandikana nawo.Pakatikati pa mphamvu yokoka ya gululo amatanthauzidwa ngati tanthauzo la masamu a ma data (XAS spectrum) a gululo.Pali mtunda wosiyanasiyana wofotokozera ma centroid oyandikana nawo ngati mtunda wa Euclidean.Pachithunzi cholowetsa cha px,y (pomwe x ndi y ali chikhazikitso mu ma pixel), CK ndiye pakati pa mphamvu yokoka ya tsango;chithunzichi chitha kugawidwa (kuphatikizana) kukhala magulu a K pogwiritsa ntchito K-means63.Masitepe omaliza a algorithm yophatikizira K-njira ndi:
Gawo 2. Werengetsani umembala wa ma pixel onse malinga ndi centroid yomwe ilipo.Mwachitsanzo, imawerengedwa kuchokera kumtunda wa Euclidean d pakati pakatikati ndi pixel iliyonse:
Khwerero 3 Patsani pixel iliyonse ku centroid yapafupi.Kenako werengeraninso malo a K centroid motere:
Gawo 4. Bwerezani ndondomekoyi (7) ndi (8)) mpaka ma centroids agwirizane.Zotsatira zamagulu omaliza amalumikizana kwambiri ndi kusankha kwabwino kwambiri kwa ma centroid oyambira.Pamapangidwe a data a PEEM a zithunzi zachitsulo, nthawi zambiri X (x × y × λ) ndi cube ya data yamtundu wa 3D, pomwe ma axes a x ndi y amayimira chidziwitso cha malo (kusintha kwa pixel) ndipo axis λ imagwirizana ndi chithunzi.chithunzi champhamvu cha spectral.Ma algorithm a K-means amagwiritsidwa ntchito pofufuza madera omwe ali ndi chidwi ndi data ya X-PEEM polekanitsa ma pixel (masango kapena ma sub-blocks) molingana ndi mawonekedwe awo owoneka bwino ndikutulutsa ma centroids abwino kwambiri (XAS spectral profiles) pa analyte aliyense.gulu).Amagwiritsidwa ntchito pophunzira kugawa kwapang'onopang'ono, kusintha kwa mawonekedwe am'deralo, machitidwe a okosijeni, ndi mayiko.Mwachitsanzo, ma algorithm a K-means clustering algorithm adagwiritsidwa ntchito kumadera a Fe L-edge ndi Cr L-edge mu X-PEEM yotentha komanso yozizira.Magulu osiyanasiyana a K (magawo a microstructure) adayesedwa kuti apeze masango ndi ma centroids abwino.Ziwerengerozi zikawonetsedwa, ma pixel amapatsidwanso ma centroids ofanana.Kugawa kwamitundu kulikonse kumafanana ndi pakati pa gululo, kuwonetsa makonzedwe apakati a zinthu zakuthupi kapena zakuthupi.Ma centroids ochotsedwa ndi mizere yophatikizika ya mawonekedwe oyera.
Deta yochirikiza zotsatira za kafukufukuyu ikupezeka pakafunsidwa koyenera kuchokera kwa wolemba WC.
Sieurin, H. & Sandström, R. Kuphwanyika kulimba kwa chitsulo chosapanga dzimbiri chowirikiza. Sieurin, H. & Sandström, R. Kuphwanyika kulimba kwa chitsulo chosapanga dzimbiri chowirikiza. Sieurin, H. & Sandström, R. Вязкость разрушения сварной дуплексной нержавеющей стали. Sieurin, H. & Sandström, R. Kuphwanyika kulimba kwa welded duplex chitsulo chosapanga dzimbiri. Sieurin, H. & Sandström, R. 焊接双相不锈钢的断裂韧性. Sieurin, H. & Sandstrom, R. 焊接双相不锈钢的断裂韧性. Sieurin, H. & Sandström, R. Вязкость разрушения сварных дуплексных нержавеющих сталей. Sieurin, H. & Sandström, R. Kuthyoka kwamphamvu kwa zitsulo zosapanga dzimbiri zosapanga dzimbiri.Britannia.Gawo laling'ono.ubweya.73, 377-390 (2006).
Adams, FV, Olubambi, PA, Potgieter, JH & Van Der Merwe, J. Corrosion resistance of duplex stainless steels muzosankhidwa organic acid ndi organic acid / chloride chilengedwe. Adams, FV, Olubambi, PA, Potgieter, JH & Van Der Merwe, J. Corrosion resistance of duplex stainless steels muzosankhidwa organic acid ndi organic acid / chloride chilengedwe.Adams, FW, Olubambi, PA, Potgieter, J. Kh.ndi Van Der Merwe, J. Corrosion resistance of duplex stainless steels m'malo okhala ndi ma organic acid ndi organic acid/chlorides. Adams, FV, Olubambi, PA, Potgieter, JH & Van Der Merwe, J. 双相不锈钢在选定的有机酸和有机酸/氯化物环境中的耐腐蚀性. Adams, FV, Olubambi, PA, Potgieter, JH & Van Der Merwe, J. 双相stainless steel在特定的organic酸和organic酸/chlorinated environment的耐过性性.Adams, FW, Olubambi, PA, Potgieter, J. Kh.ndi Van Der Merwe, J. Corrosion resistance of duplex stainless steels m'madera osankhidwa a organic acid ndi organic acid/chlorides.chosungira.Zida Njira 57, 107-117 (2010).
Barrera, S. et al.Khalidwe la Corrosion-oxidative la Fe-Al-Mn-C duplex alloys.Zida 12, 2572 (2019).
Levkov, L., Shurygin, D., Dub, V., Kosyrev, K. & Balikoev, A. M'badwo watsopano wazitsulo zapamwamba kwambiri zopangira gasi ndi mafuta. Levkov, L., Shurygin, D., Dub, V., Kosyrev, K. & Balikoev, A. M'badwo watsopano wazitsulo zapamwamba kwambiri zopangira gasi ndi mafuta.Levkov L., Shurygin D., Dub V., Kosyrev K., Balikoev A. Mbadwo watsopano wazitsulo zamtundu wapamwamba kwambiri zopangira mafuta ndi gasi.Levkov L., Shurygin D., Dub V., Kosyrev K., Balikoev A. Mbadwo watsopano wa zitsulo zapamwamba kwambiri zopangira gasi ndi mafuta.Webinar E3S 121, 04007 (2019).
Kingklang, S. & Uthaisangsuk, V. Kufufuza za khalidwe lotentha la deformation la duplex zitsulo zosapanga dzimbiri kalasi 2507. Metall. Kingklang, S. & Uthaisangsuk, V. Kufufuza za khalidwe lotentha la deformation la duplex zitsulo zosapanga dzimbiri kalasi 2507. Metall. Kingklang, S. & Uthaisangsuk, V. Исследование поведения горячей деформации дуплексной нержавеющей стали марки 2507. Metall. Kingklang, S. & Uthaisangsuk, V. Kafukufuku wa Hot Deformation Behaviour of Type 2507 Duplex Stainless Steel.Chitsulo. Kingklang, S. & Uthaisangsuk, V. 双相不锈钢2507 级热变形行為的研究. Kingklang, S. & Uthaisangsuk, V. 2507 级热变形行為的研究。Kingklang, S. ndi Utaisansuk, V. Kufufuza za Kutentha Kwambiri Makhalidwe a Mtundu wa 2507 Duplex Stainless Steel.Chitsulo.alma mater.masomphenya.48, 95-108 (2017).
Zhou, T. et al.Zotsatira za kugudubuzika kozizira pa microstructure ndi makina amakina a cerium-modified super-duplex SAF 2507 chitsulo chosapanga dzimbiri.alma mater.sayansi.Britannia.A 766, 138352 (2019).
Zhou, T. et al.Zomangamanga komanso zamakina zomwe zimayambitsidwa ndi kutentha kwa cerium-modified super-duplex SAF 2507 chitsulo chosapanga dzimbiri.J. Alma mater.thanki yosungirako.luso.9, 8379–8390 (2020).
Zheng, Z., Wang, S., Long, J., Wang, J. & Zheng, K. Mphamvu ya zinthu zapadziko lapansi zomwe sizipezeka pamtundu wotentha kwambiri wa oxidation wachitsulo cha austenitic. Zheng, Z., Wang, S., Long, J., Wang, J. & Zheng, K. Mphamvu ya zinthu zapadziko lapansi zomwe sizipezeka pamtundu wotentha kwambiri wa oxidation wachitsulo cha austenitic.Zheng Z., Wang S., Long J., Wang J. ndi Zheng K. Chikoka cha zinthu zosowa zapadziko lapansi pamachitidwe achitsulo cha austenitic pansi pa kutentha kwambiri kwa okosijeni. Zheng, Z., Wang, S., Long, J., Wang, J. & Zheng, K. 稀土元素对奥氏体钢高温氧化行為的影响. Zheng, Z., Wang, S., Long, J., Wang, J. & Zheng, K.Zheng Z., Wang S., Long J., Wang J. ndi Zheng K. Chikoka cha zinthu zapadziko zosowa pa kachitidwe ka zitsulo za austenitic pa kutentha kwambiri kwa okosijeni.koros.sayansi.164, 108359 (2020).
Li, Y., Yang, G., Jiang, Z., Chen, C. & Sun, S. Zotsatira za Ce pa microstructure ndi katundu wa 27Cr-3.8Mo-2Ni super-ferritic zitsulo zosapanga dzimbiri. Li, Y., Yang, G., Jiang, Z., Chen, C. & Sun, S. Zotsatira za Ce pa microstructure ndi katundu wa 27Cr-3.8Mo-2Ni super-ferritic zitsulo zosapanga dzimbiri.Li Y., Yang G., Jiang Z., Chen K. ndi Sun S. Mphamvu ya Se pa microstructure ndi katundu wa superferritic zitsulo zosapanga dzimbiri 27Cr-3,8Mo-2Ni. Li, Y., Yang, G., Jiang, Z., Chen, C. & Sun, S. Ce 对27Cr-3.8Mo-2Ni 超铁素体不锈钢的显微组织和性能的影响. Li, Y., Yang, G., Jiang, Z., Chen, C. & Sun, S. Mphamvu ya Ce pa microstructure ndi katundu wa 27Cr-3.8Mo-2Ni wapamwamba-zitsulo zosapanga dzimbiri. Li, Y., Yang, G., Jiang, Z., Chen, C. & Sun, S. Влияние Ce на микроструктуру и свойства суперферритной нержавеющей стали 27Cr-3,8Mo-2Ni. Li, Y., Yang, G., Jiang, Z., Chen, C. & Sun, S. Mmene Ce pa microstructure ndi katundu wa superferritic zitsulo zosapanga dzimbiri 27Cr-3,8Mo-2Ni.Chizindikiro chachitsulo.Steelmak 47, 67-76 (2020).