I-321 yensimbi engenasici edityanisiweyo yetyhubhu edityanisiweyo yeekhemikhali Iipropathi zobuchwephesha kunye nokuziphatha kokubola kwe-duplex yentsimbi engenasici kunye ne-electrode entsha.

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Insimbi engenaStainless 321 Coil Tube Chemical Ukubunjwa

Ukwakhiwa kweekhemikhali ze-321 zentsimbi ye-coil tyhubhu yentsimbi ilandelayo:
- Ikhabhoni: 0.08% max
- Manganese: 2.00% max
-Nickel: 9.00% min

Steel 321 Coil Tube Mechanical Properties Properties

NgokoMvelisi weTube yeCoil eStainless Steel 321, iipropathi zoomatshini zentsimbi engatyiwa 321 ityhubhu yekhoyili zidweliswe ngezantsi: Amandla okuqina (psi) Amandla eSivuno (psi) Ukwandiswa (%)

Usetyenziso kunye nokuSetyenziswa kweNsimbi engatyiwa 321 yeCoil Tube

Kwizicelo ezininzi zobunjineli, iipropathi zoomatshini kunye ne-corrosion ye-duplex stainless steel stainless (DSS) izakhiwo ezidityanisiweyo zezona zinto zibalulekileyo.Uphononongo lwangoku luphande iipropati zoomatshini kunye nokumelana nokubola kwe-duplex yensimbi engenasici kwi-welds kwindawo efana ne-3.5% ye-NaCl isebenzisa i-electrode entsha eyilwe ngokukodwa ngaphandle kokongezwa kwezinto ezixutywayo kwiisampuli ze-flux.Iintlobo ezimbini ezihlukeneyo zokuguquguquka kunye nesalathisi esisisiseko se-2.40 kunye ne-0.40 zisetyenziswe kwi-electrodes E1 kunye ne-E2 ye-welding DSS iibhodi, ngokulandelanayo.Ukuzinza kwe-thermal ye-flux compositions kwavavanywa kusetyenziswa uhlalutyo lwe-thermogravimetric.Ukwakheka kweekhemikhali kunye neepropathi zoomatshini kunye ne-corrosion ye-welded joints zavavanywa kusetyenziswa i-spectroscopy yokukhutshwa ngokuhambelana nemigangatho eyahlukeneyo ye-ASTM.I-X-ray diffraction isetyenziselwa ukumisela izigaba ezikhoyo kwi-welds ye-DSS, kunye ne-electron yokuskena nge-EDS isetyenziselwa ukuhlola i-microstructure ye-welds.Amandla anamandla adibeneyo adibeneyo enziwe nge-electrode ye-E1 yayingaphakathi kwe-715-732 MPa, nge-E2 electrodes - 606-687 MPa.I-welding current inyuswe ukusuka kwi-90 A ukuya kwi-110 A, kwaye ubunzima buye banda.Amalungu adityanisiweyo anee-electrode ze-E1 ezigqunywe ngee-fluxes ezisisiseko zineempawu ezingcono zoomatshini.Isakhiwo sensimbi sinokumelana okuphezulu kwe-corrosion kwindawo ye-3.5% ye-NaCl.Oku kuqinisekisa ukusebenza kwee-welded joints ezenziwe ngee-electrodes ezisanda kuphuhliswa.Iziphumo zixutyushwa ngokuchithwa kwezinto ezixutywayo ezifana ne-Cr kunye ne-Mo ezibonwe kwii-welds ezine-coated electrode E1 kunye ne-E2, kunye nokukhululwa kwe-Cr2N kwii-welds ezenziwe ngokusebenzisa i-electrodes E1 kunye ne-E2.
Ngokomlando, ukukhankanywa okusemthethweni kokuqala kwe-duplex steel stainless steel (DSS) ibuyele kwi-1927, xa yayisetyenziselwa ukuphosa okuthile kwaye ayizange isetyenziswe kwizicelo ezininzi zobugcisa ngenxa yekhabhoni ephezulu1.Kodwa emva koko, umxholo wekhabhoni oqhelekileyo uncitshiswe kwixabiso eliphezulu le-0.03%, kwaye ezi zinsimbi zaye zasetyenziswa ngokubanzi kwiindawo ezahlukeneyo2,3.I-DSS yintsapho yee-alloys malunga nezixa ezilinganayo ze-ferrite kunye ne-austenite.Uphando luye lwabonisa ukuba isigaba se-ferritic kwi-DSS sibonelela ngokhuseleko olugqwesileyo kwi-chloride-induced stress corrosion cracking (SCC), eyayingumcimbi obalulekileyo we-austenitic stainless steels (ASS) ngekhulu lama-20.Ngakolunye uhlangothi, kwezinye iinjineli kunye namanye amashishini4 imfuno yokugcina ikhula ngesantya ukuya kwi-20% ngonyaka.Le nsimbi entsha ene-austenitic-ferritic yesigaba sesibini inokufumaneka ngokukhethwa kokwakheka okufanelekileyo, ukucocwa kwe-physical-chemical and thermomechanical.Xa kuthelekiswa nenqanaba elinye lensimbi engenasici, i-DSS inamandla esivuno esiphezulu kunye nobuchule obuphezulu bokumelana ne-SCC5, 6, 7, 8. Isakhiwo se-duplex sinika ezi ntsimbi zinamandla angenakulinganiswa, ukuqina kunye nokwanda kokuxhathisa kwe-corrosion kwiindawo ezinobundlobongela ezine-acids, i-acid chlorides, amanzi olwandle kunye neekhemikhali ezonakalisayo9.Ngenxa yokuguquguquka kwexabiso lonyaka le-nickel (Ni) alloys kwimarike jikelele, isakhiwo se-DSS, ngokukodwa uhlobo lwe-nickel ephantsi (i-DSS ephilileyo), iphumelele iimpumelelo ezininzi ezigqwesileyo xa kuthelekiswa ne-face centered cubic (FCC) iron10, 11. Eyona nto iphambili Ingxaki yoyilo lwe-ASE kukuba luphantsi kweemeko ezahlukeneyo ezinzima.Ngoko ke, amasebe ahlukeneyo obunjineli kunye neenkampani zizama ukukhuthaza enye i-nickel ephantsi (i-Ni) iintsimbi ezingenasici ezenza kakuhle okanye ezingcono kune-ASS yendabuko ene-weldability efanelekileyo kwaye isetyenziswa kwizicelo zemizi-mveliso ezifana nokutshintsha ubushushu bamanzi olwandle kunye neshishini lemichiza.isikhongozeli se-13 seendawo ezingqongileyo ezinoxinzelelo oluphezulu lwekloridi.
Kwinkqubela phambili yetekhnoloji yanamhlanje, imveliso edityanisiweyo idlala indima ebalulekileyo.Ngokuqhelekileyo, amalungu esakhiwo se-DSS adityaniswa nge-gas ekhuselekileyo ye-arc welding okanye i-gas shielded arc welding.I-weld ichaphazeleka kakhulu kukubunjwa kwe-electrode esetyenziselwa ukudibanisa.I-electrodes ye-welding inamacandelo amabini: isinyithi kunye ne-flux.Ngokuqhelekileyo, i-electrodes ifakwe nge-flux, umxube wesinyithi othi, xa ubolile, ukhulule iigesi kwaye wenze i-slag ekhuselayo ukukhusela i-weld ekungcoleni, ukwandisa ukuzinza kwe-arc, kunye nokongeza i-alloying component ukuphucula umgangatho we-welding14. .Intsimbi, i-aluminiyam, intsimbi engatyiwa, intsimbi ethambileyo, intsimbi eqine kakhulu, ikopolo, ubhedu, kunye nobhedu zezinye zeentsimbi ze-electrode zokuwelda, ngelixa i-cellulose, umgubo wentsimbi, kunye nehydrogen zezinye zezinto ezisetyenziswayo.Ngamanye amaxesha i-sodium, i-titanium kunye ne-potassium nazo zongezwa kumxube we-flux.
Abanye abaphandi baye bazama ukufunda umphumo wokucwangciswa kwe-electrode kwi-mechanical and corrosion integrity of the welded steel structures.Singh et al.I-15 iphande isiphumo sokubunjwa kwe-flux kubude kunye namandla okuqina kwee-welds ezidityanisiweyo ngokuntywiliselwa kwe-arc.Iziphumo zibonisa ukuba i-CaF2 kunye ne-NiO zizona zigqibo zamandla okuqina xa kuthelekiswa nobukho be-FeMn.U-Chirag et al.16 uhlolisise i-SMAW i-compounds ngokutshintsha i-concentration ye-rutile (TiO2) kumxube we-electrode flux.Kwafunyaniswa ukuba iipropati ze-microhardness zanda ngenxa yokunyuka kwepesenti kunye nokufuduka kwekhabhoni kunye ne-silicon.UKumar [17] wafunda uyilo kunye nophuhliso lwe-agglomerated fluxes ye-arc welding entywiliweyo yamaphepha entsimbi.I-Nwigbo kunye no-Atuanya18 baphanda ukusetyenziswa kwe-potassium-rich rich sodium silicate binders ukwenzela ukuveliswa kwe-arc welding fluxes kwaye bafumene i-welds enegunya eliphezulu le-MPa ye-430 kunye nesakhiwo sengqolowa esamkelekileyo.I-Lothongkum et al.19 isebenzise indlela ye-potentiokinetic yokufunda i-volume fraction of austenite kwi-duplex steel stainless 28Cr-7Ni-O-0.34N kwisisombululo se-NaCl esigcwele umoya kwi-concentration ye-3.5% wt.phantsi kweemeko ze-pH.kunye nama-27°C.Zombini i-duplex kunye ne-micro duplex steels stainless zibonisa isiphumo esifanayo se-nitrogen ekuziphatheni komhlwa.I-Nitrogen ayizange ichaphazele amandla okuhlwa okanye izinga le-pH 7 kunye ne-10, nangona kunjalo, amandla okubola kwi-pH 10 yayingaphantsi kune-pH 7. Ngakolunye uhlangothi, kuwo onke amanqanaba e-pH afundwayo, amandla aqala ukwanda ngokunyuka komxholo we-nitrogen. .Lacerda et al.I-20 ifunde i-pitting ye-duplex stainless steels UNS S31803 kunye ne-UNS S32304 kwi-3.5% isisombululo se-NaCl usebenzisa i-cyclic potentiodynamic polarization.Kwisisombululo se-3.5 wt.% se-NaCl, iimpawu ze-pitting zifunyenwe kwiiplati zetsimbi ezimbini eziphandwayo.I-UNS S31803 insimbi inamandla aphezulu okubola (i-Ecorr), i-pitting potential (Epit) kunye nokumelana ne-polarization (Rp) kune-UNS S32304 yensimbi.Intsimbi ye-UNS S31803 ine-repassivity ephezulu kune-UNS S32304 yentsimbi.Ngokutsho kophando olwenziwa nguJiang et al.[21], incopho yokuvuselela ehambelana nesigaba esiphindwe kabini (i-austenite kunye nesigaba se-ferrite) ye-duplex yensimbi engenasici ibandakanya ukuya kwi-65% yokwakheka kwe-ferrite, kwaye ukuxinana kwe-ferrite kwangoku kwanda ngokunyuka kwexesha lonyango lokushisa.Kuyaziwa ukuba izigaba ze-austenitic kunye ne-ferritic zibonisa ukuphendulwa kwe-electrochemical eyahlukeneyo kwi-electrochemical potentials21,22,23,24.U-Abdo et al.25 basebenzise imilinganiselo ye-potentiodynamic ye-polarization spectroscopy kunye ne-electrochemical impedance spectroscopy ukufunda i-electrochemically induced corrosion ye-laser-welded 2205 DSS alloy kumanzi olwandle okwenziwa (3.5% NaCl) phantsi kweemeko ze-asidi ehlukeneyo kunye ne-alkalinity.Ukonakala komngxuma kujongwe kwiindawo ezivelileyo zesampulu evavanyiweyo ye-DSS.Ngokusekelwe kwezi ziphumo, kwasekwa ukuba kukho ubudlelwane obulinganayo phakathi kwe-pH yendawo yokuchithwa kunye nokuchasana kwefilimu eyenziwe kwinkqubo yokudluliselwa kwentlawulo, echaphazela ngokuthe ngqo ukubunjwa kwe-pitting kunye neenkcukacha zayo.Injongo yolu phononongo yayikukuqonda indlela ukwakhiwa kwe-welding electrode esanda kuphuhliswa kuchaphazela ngayo ingqibelelo yomatshini kunye ne-wear-resistant ye-welded DSS 2205 kwindawo ye-3.5% ye-NaCl.
Iiminerali ezixutywayo (izithako) ezisetyenziswe kwi-electrode coating formulations yiCalcium Carbonate (CaCO3) esuka kwiSithili saseObajana, kwiSithili saseKogi, eNigeria, iCalcium Fluoride (CaF2) esuka kwiTaraba State, Nigeria, Silicon Dioxide (SiO2), Talc Powder (Mg3Si4O10 (OH). )) 2) kunye ne-rutile (TiO2) yafunyanwa kuJos, eNigeria, kunye ne-kaolin (Al2 (OH) 4Si2O5) yafunyanwa eKankara, eKatsina State, eNigeria.I-Potassium silicate isetyenziswa njenge-binder, ifumaneka eIndiya.
Njengoko kubonisiwe kwiThebhile 1, i-oxides ekhoyo yayilinganiswa ngokuzimeleyo kwibhalansi yedijithali.Emva koko yaxutywa kunye ne-potassium silicate binder (23% ngesisindo) kwi-mixer yombane (imodeli: 641-048) esuka kwi-Indian Steel kunye ne-Wire Products Ltd. (ISWP) imizuzu ye-30 ukufumana i-homogeneous semi-solid paste.I-flux edibeneyo emanzi ixinzelelwe kwisimo se-cylindrical ukusuka kumatshini we-briquetting kwaye ifakwe kwigumbi lokukhupha ngoxinzelelo lwe-80 ukuya kwi-100 kg / cm2, kwaye ukusuka kwigumbi lokutya locingo lifakwe kwi-3.15mm ububanzi be-stainless wire extruder.I-flux isondliwa nge-nozzle / die system kwaye ifakwe kwi-extruder ukuze ikhuphe i-electrodes.I-1.70 mm ye-coverage factor yafunyanwa, apho i-coverage factor ichazwa njengomlinganiselo we-electrode diameter kwi-diameter ye-strand.Emva koko i-electrode edibeneyo yomiswa emoyeni kwiiyure ezingama-24 kwaye emva koko i-calcined kwisithando somlilo se-muffle (imodeli PH-248-0571 / 5448) kwi-150-250 ° C \ (-\) kwiiyure ze-2.Sebenzisa i-equation ukubala ialkalinity yokuhamba.(1) 26;
Ukuzinza kwe-thermal yeesampuli ze-flux zokuqamba i-E1 kunye ne-E2 yagqitywa ngokusebenzisa uhlalutyo lwe-thermogravimetric (TGA).Isampuli malunga ne-25.33 mg ye-flux ilayishwe kwi-TGA ukuze ihlalutywe.Iimvavanyo zenziwa kwi-inert medium efunyenwe ngokuhamba okuqhubekayo kwe-N2 kwizinga le-60 ml / min.Isampuli yatshiswa ukusuka kwi-30 ° C ukuya kwi-1000 ° C kwiqondo lokushisa le-10 ° C / min.Ukulandela iindlela ezichazwe nguWang et al.27, Xu et al.28 kunye noDagwa et al.29, ukuchithwa kwe-thermal kunye nokulahlekelwa kwesisindo seesampuli kumaqondo okushisa athile ahlolwe kwiiplani ze-TGA.
Inkqubo ezimbini ze-300 x 60 x 6 mm iipleyiti ze-DSS ukulungiselela i-soldering.I-V-groove yenzelwe i-3mm yengcambu yengcambu, i-2mm ye-root ye-root kunye ne-angle ye-groove ye-60 °.Emva koko ipleyiti yahlanjululwa nge-acetone ukuze kususwe ukungcola okunokwenzeka.Weld iipleyiti usebenzisa i-shielded metal arc welder (SMAW) kunye ne-electrode yangoku echanekileyo ye-polarity (DCEP) usebenzisa i-electrode edibeneyo (E1 kunye ne-E2) kunye ne-electrode yereferensi (C) enobubanzi obuyi-3.15 mm.I-Electrical Discharge Machining (EDM) (Imodeli: I-Excetek-V400) yayisetyenziselwa umatshini wemifuziselo yentsimbi edityanisiweyo yokuvavanywa komatshini kunye nokubonakaliswa kwe-corrosion.Itheyibhile yesi-2 ibonisa ikhowudi yomzekelo kunye nenkcazo, kwaye iThebhile 3 ibonisa iiparitha ezahlukeneyo zokusebenza ze-welding ezisetyenziselwa ukudibanisa ibhodi ye-DSS.I-equation (2) isetyenziselwa ukubala igalelo lobushushu elihambelanayo.
Ukusebenzisa i-Bruker Q8 MAGELLAN i-spectrometer optical emission (OES) ene-wavelength ye-110 ukuya kwi-800 nm kunye ne-SQL ye-software yedatha yedatha, ukubunjwa kweekhemikhali ze-weld joints of electrode E1, E2 kunye ne-C, kunye neesampuli zesiseko sesinyithi, sinqunywe.isebenzisa isithuba phakathi kwe-electrode kunye nesampuli yesinyithi phantsi kovavanyo Ivelisa amandla ombane ngendlela yentlantsi.Isampulu yamacandelo ifakwe umphunga kwaye itshizwe, ilandelwa yi-atomic excitation, ethi emva koko ikhuphe i-spectrum yomgca31.Uhlalutyo olusemgangathweni lwesampulu, i-tube ye-photomultiplier ilinganisa ubukho be-spectrum ezinikeleyo kwinto nganye, kunye nobukhulu be-spectrum.Emva koko sebenzisa i-equation ukubala inombolo yokumelana ne-pitting elinganayo (PREN).(3) Umlinganiselo we-32 kunye ne-WRC 1992 ye-state diagram isetyenziselwa ukubala i-chromium kunye ne-nickel equivalents (Creq ne-Nieq) ukusuka kwi-equations.(4) no-(5) ngama-33 nama-34 ngokulandelelanayo;
Qaphela ukuba i-PREN ithatha kuphela ingqalelo kwimpembelelo emihle yezinto ezintathu eziphambili ze-Cr, i-Mo kunye ne-N, ngelixa i-nitrogen factor x ikwi-16-30.Ngokuqhelekileyo, i-x ikhethwe kuluhlu lwe-16, i-20, okanye i-30. Kuphando kwi-duplex stainless steels, ixabiso eliphakathi kwe-20 lisetyenziswa ngokuqhelekileyo ukubala ixabiso le-PREN35,36.
Amalungu adityanisiweyo awenziwe kusetyenziswa i-electrode eyahlukeneyo avavanyiwe kumatshini wovavanyo wendalo yonke (Instron 8800 UTM) kwinqanaba loxinzelelo lwe-0.5 mm / min ngokuhambelana ne-ASTM E8-21.Amandla e-tensile (UTS), i-0.2% yamandla e-shear yield (YS), kunye nobude babalwa ngokwe-ASTM E8-2137.
I-weldments ye-DSS 2205 yayiqala phantsi kwaye ipolishiwe kusetyenziswa ubungakanani obuhlukeneyo begrit (120, 220, 320, 400, 600, 800, 1000 kunye ne-1200) phambi kohlalutyo lobunzima.Iisampuli ezidibeneyo zenziwe nge-electrode E1, E2 kunye ne-C. Ubunzima bulinganiswa kwiindawo ezilishumi (10) ukusuka kumbindi we-weld ukuya kwisiseko sesinyithi kunye nekhefu le-1 mm.
I-X-ray diffractometer (i-D8 Discover, i-Bruker, eJamani) iqulunqwe kunye ne-software ye-Bruker XRD Commander yokuqokelela idatha kunye ne-Fe-filtered Cu-K-α radiation enamandla e-8.04 keV ehambelana nobude be-1.5406 Å kunye nomlinganiselo wokuskena we-3 ° Uluhlu lokuskena (2θ) i-min-1 yi-38 ukuya kwi-103 ° yokuhlalutya kwesigaba kunye ne-E1, i-E2 kunye ne-C kunye ne-BM electrode ekhoyo kwii-welds ze-DSS.Indlela yokucoca yaseRietveld isetyenziselwe ukukhomba izigaba ezimiselweyo usebenzisa isoftware ye-MAUD echazwe nguLutterotti39.Ngokusekelwe kwi-ASTM E1245-03, uhlalutyo lwe-metallographic yobuninzi bemifanekiso emincinci ye-weld joints of electrode E1, E2 kunye ne-C yenziwa ngokusebenzisa i-software ye-Image J40.Iziphumo zokubala iqhezu lomthamo wesigaba se-ferrite-austenitic, ixabiso labo eliphakathi kunye nokuphambuka kunikwe kwiThebhile.5. Njengoko kuboniswe kwisampulu yoqwalaselo kwifig.I-6d, uhlalutyo lwe-optical microscopy (OM) lwenziwa kwi-PM kunye ne-welded joints kunye ne-electrodes E1 kunye ne-E2 ukufunda i-morphology yeesampuli.Iisampulu zapholishwa nge-120, 220, 320, 400, 600, 800, 1000, 1200, 1500, kunye ne-2000 grit silicon carbide (SiC) sandpaper.Iisampulu zaye zafakwa nge-electrolytically kwi-10% yesisombululo se-aqueous oxalic acid kwiqondo lokushisa lokushisa kwi-voltage ye-5 V kwi-10 s kwaye ibekwe kwi-LEICA DM 2500 M i-microscope ebonakalayo ye-morphological characterization.Ukupholiswa ngakumbi kwesampulu kwenziwa kusetyenziswa iphepha le-2500 grit silicon carbide (SiC) kuhlalutyo lwe-SEM-BSE.Ukongeza, amajoyinti adityanisiweyo avavanyelwe i-microstructure kusetyenziswa i-ultra-high resolution field emission scanning electron microscope (SEM) (FEI NOVA NANOSEM 430, USA) exhotyiswe nge-EMF.Isampula ye-20 × 10 × 6 mm yachithwa kusetyenziswa i-sandpapers ye-SiC eyahlukeneyo ukusuka kwi-120 ukuya kwi-2500. Iisampuli zazifakwe nge-electrolytically kwi-40 g ye-NaOH kunye ne-100 ml yamanzi adibeneyo kumbane we-5 V kwi-15 s, emva koko. ifakwe kumphathi wesampula, ebekwe kwigumbi le-SEM, ukuhlalutya iisampuli emva kokucoca igumbi nge-nitrogen.I-electron beam eyenziwe yi-tungsten filament evuthayo yenza i-grating kwisampuli ukuvelisa imifanekiso kwiindidi ezahlukeneyo, kwaye iziphumo ze-EMF zifunyenwe ngokusebenzisa iindlela zikaRoche et al.41 kunye neMokobi 42.
Indlela ye-electrochemical potentiodynamic polarization ngokwe-ASTM G59-9743 kunye ne-ASTM G5-1444 yayisetyenziselwa ukuvavanya amandla okuthotywa kwe-DSS 2205 plates welded kunye ne-E1, i-E2 kunye ne-C electrode kwindawo ye-3.5% ye-NaCl.Iimvavanyo ze-Electrochemical zenziwa kusetyenziswa i-computer-controlled Potentiostat-Galvanostat / ZRA apparatus (imodeli: PC4 / 750, Gamry Instruments, USA).Uvavanyo lwe-electrochemical lwenziwa kuvavanyo lwe-electrode emithathu: i-DSS 2205 njenge-electrode esebenzayo, i-calomel electrode egcweleyo (SCE) njenge-electrode yereferensi kunye nentonga yegraphite njenge-counter electrode.Imilinganiselo yenziwa kusetyenziswa iseli ye-electrochemical, apho indawo yesenzo sesisombululo yayiyindawo ye-electrode esebenzayo eyi-0.78 cm2.Imilinganiselo yenziwe phakathi kwe--1.0 V ukuya kwi-1.6 V enokubakho kwi-OCP yangaphambili (enxulumene ne-OCP) kwisantya sokuskena se-1.0 mV / s.
I-Electrochemical pitting iimvavanyo ezibalulekileyo zeqondo lokushisa zenziwe kwi-3.5% ye-NaCl ukuvavanya ukunyanzeliswa kwe-pitting ye-welds eyenziwe nge-E1, E2, kunye ne-C electrode.ngokucacileyo kwi-pitting potential kwi-PB (phakathi kwemimandla ye-passive kunye ne-transpassive), kunye ne-welded specimens kunye ne-E1, i-E2, i-Electrodes C. Ngoko ke, imilinganiselo ye-CPT iyenziwa ukucacisa ngokuchanekileyo amandla okubamba i-welding consumables.Uvavanyo lwe-CPT lwenziwe ngokuhambelana ne-duplex yensimbi engenasici yeengxelo ze-weld45 kunye ne-ASTM G150-1846.Ukusuka kwintsimbi nganye ekufuneka idityaniswe (S-110A, E1-110A, E2-90A), iisampulu ezinommandla we-1 cm2 zasikwa, kubandakanya isiseko, i-weld, kunye nemimandla ye-HAZ.Iisampulu zapolishwa kusetyenziswa iphepha lesanti kunye nodaka oluludaka lwe-alumina oluyi-1 µm ngokuhambelana neenkqubo eziqhelekileyo zokulungiselela isampulu yesampulu.Emva kokupholisha, iisampuli zahlanjululwa nge-ultrasonically kwi-acetone ye-2 min.Isisombululo se-3.5% sovavanyo lwe-NaCl songezwa kwiseli yovavanyo lwe-CPT kwaye ukushisa kokuqala kwahlengahlengiswa kwi-25 ° C usebenzisa i-thermostat (i-Neslab RTE-111).Emva kokufikelela kwiqondo lokushisa lokuqala lokuvavanya kwe-25 ° C, i-Ar gas yavuthela i-15 min, emva koko iisampuli zafakwa kwiseli, kwaye i-OCF ilinganiswe kwi-15 min.Isampuli yabe isenziwa i-polarized ngokusebenzisa i-voltage ye-0.3 V kwiqondo lokushisa lokuqala le-25 ° C, kwaye okwangoku kulinganiswe kwi-10 min45.Qalisa ukufudumeza isisombululo kwisantya se-1 °C/min ukuya kwi-50 °C.Ngethuba lokufudumala kwesisombululo sovavanyo, inzwa yokushisa isetyenziselwa ukujonga ngokuqhubekayo ukushisa kwesisombululo kunye nokugcina ixesha kunye nedatha yeqondo lokushisa, kwaye i-potentiostat / galvanostat isetyenziselwa ukulinganisa okwangoku.I-electrode yegraphite isetyenziswe njenge-electrode ye-counter, kwaye zonke izinto ezinokubakho zilinganiswa ngokumalunga ne-electrode yereferensi ye-Ag/AgCl.I-Argon purge yenziwa kulo lonke uvavanyo.
Kwikhiwane.I-1 ibonisa ukubunjwa (ngeepesenti zobunzima) zecandelo le-flux F1 kunye ne-F2 esetyenziselwa ukuveliswa kwe-alkaline (E1) kunye ne-acidic (E2) electrodes, ngokulandelanayo.Isalathiso sesiseko se-flux sisetyenziselwa ukuqikelela iipropathi zoomatshini kunye ne-metallurgical yamalungu adityanisiweyo.I-F1 licandelo le-flux esetyenziselwa ukwambathisa i-E1 electrode, ebizwa ngokuba yi-alkaline flux kuba isalathiso sayo esisisiseko yi-> 1.2 (okt 2.40), kunye ne-F2 yi-flux esetyenziselwa ukugubungela i-electrodes ye-E2, ebizwa ngokuba yi-asidi flux ngenxa yesiseko sayo. isalathisi < 0.9 (okt 2.40).0.40).Kucacile ukuba i-electrodes egqunywe ngee-fluxes ezisisiseko kwiimeko ezininzi zineepropati ezingcono zomatshini kune-electrode ezigqunywe nge-acidic fluxes.Olu phawu ngumsebenzi wokulawula i-oxide esisiseko kwinkqubo yokwakheka kwe-flux ye-electrode E1.Ngokuchasene noko, ukususwa kwe-slag (ukwahlula) kunye ne-spatter ephantsi ebonwa kumalungu adityanisiweyo nge-electrodes ye-E2 yimpawu ye-electrodes ene-acidic flux coating kunye nomxholo ophezulu we-rutile.Olu qwalaselo luhambelana neziphumo ze-Gill47 ukuba umphumo we-rutile umxholo kwi-slag detachability kunye ne-spatter ephantsi ye-acid flux coated electrode igalelo ekukhenkceni kwe-slag ngokukhawuleza.I-Kaolin kwinkqubo ye-flux esetyenziselwa ukugqoka i-electrodes E1 kunye ne-E2 yayisetyenziswe njenge-lubricant, kwaye i-talc powder yaphucula ukugqithiswa kwee-electrodes.I-Potassium silicate binders kwiinkqubo ze-flux igalelo ekutshiseni i-arc engcono kunye nokuzinza kokusebenza, kwaye, ngaphezu kweempawu zabo zokubambelela, ukuphucula ukuhlukana kwe-slag kwiimveliso ezidibeneyo.Ekubeni i-CaCO3 i-net breaker (i-slag breaker) kwi-flux kwaye ithambekele ekuveliseni umsi omningi ngexesha le-welding ngenxa yokubola kwe-thermal kwi-CaO kunye ne-44% ye-CO2, i-TiO2 (njengomakhi womnatha / i-slag yangaphambili) inceda ukunciphisa inani. umsi ngexesha le-welding.i-welding kwaye ngaloo ndlela iphucula ukuchithwa kwe-slag njengoko kucetyiswe nguJing et al.48.I-Fluorine Flux (i-CaF2) yi-flux eyingozi yekhemikhali ephucula ukucoceka kwe-solder.Jastrzębska et al.I-49 ichaze umphumo wokwakhiwa kwe-fluoride yolu qulunqo lwe-flux kwiipropati zococeko lwe-weld.Ngokuqhelekileyo, i-flux yongezwa kwindawo ye-weld ukuphucula ukuzinza kwe-arc, ukongeza izinto ze-alloying, ukwakha i-slag, ukwandisa imveliso, kunye nokuphucula umgangatho we-weld pool 50.
Iigophe ze-TGA-DTG eziboniswe kwiMifanekiso.I-2a kunye ne-2b ibonisa ukwehla kobunzima obuthathu ekufudumezeni kwiqondo lokushisa elingu-30-1000 ° C kwi-nitrogen emoyeni.Iziphumo kwiFigure 2a kunye ne-b zibonisa ukuba iisampulu ezisisiseko kunye ne-acidic flux, ijika le-TGA lehla ngokuthe ngqo de ekugqibeleni lihambelane ne-axis yobushushu, malunga ne-866.49 ° C kunye ne-849.10 ° C ngokulandelelanayo.Ukulahlekelwa kwesisindo se-1.30% kunye ne-0.81% ekuqaleni kwee-curves ze-TGA kwi-Fig. 2a kunye ne-2b ngenxa yomswakama othathwe ngamacandelo e-flux, kunye nokunyuka kunye nokuphelelwa amandla kwamanzi okumanzi komhlaba.Ukuchithwa okuphambili kweesampuli ze-flux eziphambili kwinqanaba lesibini kunye nelesithathu kwifig.I-2a yenzeke kwiindawo zokushisa kwe-619.45 ° C-766.36 ° C kunye ne-766.36 ° C-866.49 ° C, kwaye ipesenti yokulahlekelwa kwesisindo sayo yi-2.84 kunye ne-9.48%., ngokulandelelanayo.Ngelixa iisampulu ze-acidic flux kwi-Fig. 7b, ezaziphakathi kweqondo lokushisa kwe-665.23 ° C-745.37 ° C kunye ne-745.37 ° C-849.10 ° C, ipesenti yabo yokulahlekelwa kwesisindo yayingu-0.81 kunye ne-6.73%, ngokulandelanayo, okubangelwa ukuba ukubola thermal.Ekubeni amacandelo e-flux e-inorganic, i-volatiles inqunyelwe kumxube we-flux.Ke ngoko, ukunciphisa kunye ne-oxidation iyoyikeka.Oku kuhambelana neziphumo zeBalogun et al.51, uKamli et al.52 kunye no-Adeleke et al.53.Isixa selahleko yobunzima besampulu ye-flux ebonwe kwifig.I-2a kunye ne-2b yi-13.26% kunye ne-8.43%, ngokulandelanayo.Ukulahleka okuncinci kobunzima beesampulu ze-flux kwifig.I-2b ingenxa yeendawo eziphezulu zokunyibilika kwe-TiO2 kunye ne-SiO2 (i-1843 kunye ne-1710 ° C ngokulandelanayo) njenge-oxides eziphambili ezenza umxube we-flux54,55, ngelixa i-TiO2 kunye ne-SiO2 inamaphuzu aphantsi okuncibilika.indawo yokunyibilika I-oxide ephambili: i-CaCO3 (825 °C) kwisampulu ye-flux kwifig.2a56.Olu tshintsho kwindawo yokunyibilika kwee-oxides eziphambili kwiingxube ze-flux zichazwe kakuhle nguShi et al.54, uRingdalen et al.55 kunye noDu et al.56.Ukuqwalasela ukulahleka kwesisindo esiqhubekayo kwi-Fig. 2a kunye ne-2b, kunokugqitywa ukuba iisampulu ze-flux ezisetyenziswe kwi-E1 kunye ne-E2 yokugqoka i-electrode zenza ukuchithwa kwenyathelo elinye, njengoko kucetyiswa nguBrown57.Uluhlu lwamaqondo obushushu benkqubo lunokubonwa kwi-derivative curves (wt%) kwifig.2a kunye no b.Ekubeni i-curve ye-TGA ayikwazi ukuchaza ngokuchanekileyo iqondo lokushisa elithile apho inkqubo ye-flux ithatha ukuguqulwa kwesigaba kunye ne-crystallization, i-derivative ye-TGA isetyenziselwa ukugqiba ixabiso elichanekileyo lokushisa kwento nganye (utshintsho lwesigaba) njenge-peak endothermic ukulungiselela inkqubo ye-flux.
Iijika ze-TGA-DTG ezibonisa ukuchithwa kwe-thermal (a) i-alkaline flux ye-E1 electrode coating kunye (b) ne-acidic flux ye-E2 electrode coating.
Itheyibhile 4 ibonisa iziphumo zohlalutyo lwe-spectrophotometric kunye nohlalutyo lwe-SEM-EDS ye-DSS 2205 isiseko sesinyithi kunye ne-welds ezenziwe ngokusebenzisa i-E1, i-E2 kunye ne-C electrodes.I-E1 kunye ne-E2 ibonise ukuba umxholo we-chromium (Cr) wehla ngokukhawuleza ukuya kwi-18.94 kunye ne-17.04%, kwaye umxholo we-molybdenum (Mo) wawuyi-0.06 kunye ne-0.08%, ngokulandelanayo.amaxabiso e-welds nge-electrode E1 kunye ne-E2 aphantsi.Oku kuhambelana kancinane nexabiso le-PREN elibalwe kwisigaba se-ferritic-austenitic ukusuka kuhlalutyo lwe-SEM-EDS.Ngoko ke, kunokubonwa ukuba i-pitting iqala kwinqanaba kunye nexabiso eliphantsi le-PREN (i-welds ukusuka kwi-E1 kunye ne-E2), ngokusisiseko njengoko kuchazwe kwiThebhile 4. Oku kubonisa ukuchithwa kunye nokunyuka kwemvula ye-alloy kwi-weld.Emva koko, ukuncitshiswa komxholo we-Cr kunye ne-Mo alloying element kwii-welds eziveliswa kusetyenziswa i-electrodes E1 kunye ne-E2 kunye nexabiso labo eliphantsi lokubeka amaxabiso alinganayo (PREN) aboniswe kwiThebhile 4, eyenza ingxaki yokugcina ukuchasana kwiindawo ezinobundlobongela, ngakumbi. kwiindawo zekloridi.-esiqulathe indawo.Umxholo we-nickel (Ni) ophezulu kakhulu we-11.14% kunye nomda ovumelekileyo womxholo we-manganese kwiindawo ezidibeneyo ze-electrode ye-E1 kunye ne-E2 inokuba nefuthe elihle kwiipropati ze-mechanical weldments ezisetyenziswa kwiimeko ezifanisa amanzi olwandle (Umfanekiso 3). ).zenziwe ngokusebenzisa umsebenzi we-Yuan kunye ne-Oy58 kunye no-Jing et al.48 kwimpembelelo ye-nickel ephezulu kunye neengqungquthela ze-manganese ekuphuculeni iimpawu ze-mechanical ze-DSS ezidibeneyo phantsi kweemeko zokusebenza ezinzima.
Iziphumo zovavanyo lwe-tensile ye-(a) ye-UTS kunye ne-0.2% sag YS kunye (b) iyunifomu kunye nobude obupheleleyo kunye nokutenxa kwabo okusemgangathweni.
Iimpawu zamandla ezinto ezisisiseko (BM) kunye nokudibanisa okudibeneyo okwenziwe kwi-electrode ephuhlisiwe (E1 kunye ne-E2) kunye ne-electrode ekhoyo yorhwebo (C) yavavanywa kwiimbini ze-welding currents ze-90 A kunye ne-110 A. 3 (a) kunye (b) bonisa i-UTS, i-YS kunye ne-0.2% ye-offset, kunye nedatha yazo yobude kunye ne-standard deviation data.Iziphumo ze-UTS kunye ne-YS ze-offset ze-0.2% ezifunyenwe kwi-Figs.3a bonisa amaxabiso afanelekileyo kwisampulu yenombolo.1 (BM), isampuli no.3 (weld E1), isampuli no.5 (weld E2) kunye nesampuli no.I-6 (i-welds ene-C) yi-878 kunye ne-616 MPa, i-732 kunye ne-497 MPa, i-687 kunye ne-461 ye-MPa kunye ne-769 kunye ne-549 MPa, ngokulandelelana, kunye nokutenxa kwemigangatho.Ukususela kwikhiwane.110 A) ziisampulu ezinenombolo 1, 2, 3, 6 no-7, ngokulandelelanayo, kunye neepropati ezicetyiswayo zokuqina ezingaphezulu kwe-450 MPa kuvavanyo lwe-tensile kunye ne-620 MPa kuvavanyo lwe-tensile olucetywe nguGrocki32.Ukwandiswa kweesampuli ze-welding kunye ne-electrodes E1, E2 kunye ne-C, emele iisampuli ze-2, i-3, i-4, i-5, i-6 kunye ne-7, kwi-welding currents ye-90 A kunye ne-110 A, ngokulandelelana, ibonisa iplastiki kunye nokunyaniseka.malunga nesiseko sesinyithi.I-elongation ephantsi yachazwa yiziphene ze-welding ezinokwenzeka okanye ukubunjwa kwe-electrode flux (Umfanekiso 3b).Kunokuqukunjelwa ukuba i-BM duplex yensimbi engenasici kunye ne-welded joints kunye ne-E1, i-E2 kunye ne-C electrode ngokubanzi ineempawu eziphezulu kakhulu zokuqina ngenxa yomxholo we-nickel ephezulu (Itheyibhile 4), kodwa le propati yabonwa kumalungu adityanisiweyo.I-E2 encinci esebenzayo ifunyenwe kwi-acidic composition of flux.I-Gunn59 ibonise isiphumo se-nickel alloys ekuphuculeni iimpawu ze-mechanical ze-welded joints kunye nokulawula ukulingana kwesigaba kunye nokuhanjiswa kwezinto.Oku kwakhona kuqinisekisa into yokuba i-electrodes eyenziwe kwi-basic flux compositions ineepropathi ezingcono zoomatshini kunee-electrodes ezenziwe kwimixube ye-acidic flux, njengoko kucetyiswa ngu-Bang et al.60.Ngaloo ndlela, igalelo elibalulekileyo lenziwe kulwazi olukhoyo malunga neepropati ze-welded joint of the new coated electrode (E1) eneempawu ezintle zokuqina.
Kwikhiwane.Amanani 4a kunye ne-4b abonisa iimpawu ze-Vickers microhardness zeesampuli zokulinga ze-welded joints of electrode E1, E2 kunye ne-C. 4a ibonisa iziphumo zobunzima ezifunyenwe kwelinye icala lesampuli (ukusuka kwi-WZ ukuya kwi-BM), kunye nomkhiwane.I-4b ibonisa iziphumo zobunzima ezifunyenwe kumacala omabini esampuli.Amaxabiso obunzima afunyenwe ngexesha lokuwelda iisampulu zeNombolo 2, 3, 4 kunye ne-5, ezidityaniswe ngokudibeneyo nge-electrode E1 kunye ne-E2, zinokubakho ngenxa yesakhiwo esicolekileyo ngexesha lokuqina kwimijikelo ye-welding.Ukunyuka okubukhali kobunzima kwabonwa kokubili kwi-HAZ ene-coarse-grained kunye ne-HAZ ye-fine-grained yazo zonke iisampuli ze-2-7 (jonga iikhowudi zesampula kwiThebhile 2), enokuchazwa ngotshintsho olunokwenzeka kwi-microstructure i-weld ngenxa yeesampulu ze-chromium-weld zizityebi kwi-emissions (Cr23C6) .Xa kuthelekiswa nezinye iisampuli ze-welding 2, 3, 4 kunye ne-5, amaxabiso obunzima be-welded joints of samples No. 6 kunye ne-7 kumakhiwane.4a kunye no-4b ngaphezulu (Itheyibhile 2).Ngokuka-Mohammed et al.61 kunye noNowacki no-Lukoje62, oku kusenokuba ngenxa yexabiso eliphezulu le-ferrite δ kunye noxinzelelo lwentsalela ye-weld kwi-weld, kunye nokuncipha kwezinto ezidibeneyo ezifana ne-Mo kunye ne-Cr kwi-weld.Amaxabiso obunzima bazo zonke iisampulu zovavanyo kwindawo ye-BM zibonakala ngathi ziyaguquguquka.Umkhwa kwiziphumo zohlalutyo lobulukhuni beesampuli ezidibeneyo zihambelana nezigqibo zabanye abaphandi61,63,64.
Amaxabiso okuqina okudityanisiweyo okudityanisiweyo kwisampulu ye-DSS (a) isiqingatha secandelo leesampulu ezidityanisiweyo kunye (b) necandelo elipheleleyo lamalungu adityanisiweyo.
Izigaba ezahlukeneyo ezikhoyo kwi-welded DSS 2205 kunye ne-E1, i-E2 kunye ne-C electrode zifunyenwe kwaye i-spectra ye-XRD ye-angle ye-diffraction 2 \ (\ theta \) iboniswe kwi-Fig. 5. Iincopho ze-austenite (\(\ gamma\) ) kunye nezigaba ze-ferrite (\(\ alpha\)) zichongiwe kwii-angles ze-diffraction ze-43 ° kunye ne-44 °, ziqinisekisa ngokuqinisekileyo ukuba ukubunjwa kwe-weld yintsimbi ephindwe kabini ye-65 stainless steel.ukuba i-DSS BM ibonisa kuphela izigaba ze-austenitic (\(\gamma\)) kunye ne-ferritic (\(\alpha\)), eqinisekisa iziphumo ze-microstructural ezinikezelwe kwiMifanekiso 1 kunye ne-2. 6c, 7c kunye ne-9c.Isigaba se-ferritic (\ (\ alpha \)) esibonwayo kunye ne-DSS BM kunye nencopho ephezulu kwi-weld ukuya kwi-electrode C ibonisa ukuxhathisa kwayo, ekubeni esi sigaba sijolise ekunyuseni ukuxhathisa kwentsimbi, njengoko uDavison kunye ne-Redmond66 banayo. ixeliwe, ubukho bezinto zokuzinzisa i-ferrite, ezifana ne-Cr kunye ne-Mo, izinzisa ngokufanelekileyo ifilimu ye-passive yezinto eziphathekayo kwiindawo ezine-chloride.Itheyibhile 5 ibonisa isigaba se-ferrite-austenitic nge-quantitative metallography.Umlinganiselo wesahlulo somthamo wesigaba se-ferrite-austenitic kumalungu adibeneyo e-electrode C aphunyezwe malunga (≈1: 1).I-ferrite ephantsi (\ (\ alpha \)) ukubunjwa kwesigaba se-weldments usebenzisa i-E1 kunye ne-E2 i-electrodes kwimiphumo ye-volume fraction (Itheyibhile 5) ibonisa uvakalelo olunokwenzeka kwindawo enobungozi, eyaqinisekiswa ngohlalutyo lwe-electrochemical.iqinisekisiwe (Umfanekiso we-10a, b)), ekubeni isigaba se-ferrite sinikeza amandla aphezulu kunye nokukhuselwa kwi-chloride-induced stress corrosion cracking.Oku kuqinisekiswa ngakumbi ngamaxabiso obunzima obuphantsi obujongwe kwii-welds ze-electrode E1 kunye ne-E2 kwifig.4a,b, ezibangelwa umlinganiselo ophantsi we-ferrite kwisakhiwo sensimbi (Itheyibhile 5).Ubukho be-austenitic engalinganiyo (\ (\ gamma \)) kunye ne-ferritic (\ (\ alpha \)) izigaba kwiindawo ezidibeneyo ezidibeneyo usebenzisa i-electrodes ye-E2 ibonisa umngcipheko wangempela wensimbi kwi-uniform corrosion attack.Ngokuchasene noko, i-XPA spectra yeentsimbi zesigaba ezibini ze-welded joints kunye ne-E1 kunye ne-C electrode, kunye neziphumo ze-BM, zihlala zibonisa ubukho be-austenitic kunye ne-ferritic stabilizing element, eyenza ukuba izinto zibe luncedo kulwakhiwo kunye neshishini lepetrochemical. , kuba waxoxa uJimenez et al.65;Davidson & Redmond66;UShamant nabanye67.
Iimicrographs zamehlo ezidityanisiweyo zee-electrode ze-E1 ezinejiometri edityanisiweyo: (a) I-HAZ ebonisa umgca wokudityaniswa, (b) I-HAZ ebonisa umgca wokudityaniswa kulwandiso oluphezulu, (c) i-BM yesigaba se-ferritic-austenitic, (d) i-weld geometry , (e) Ibonisa indawo yotshintsho ekufutshane, (f) I-HAZ ibonisa isigaba se-ferritic-austenitic kulwandiso oluphezulu, (g) Indawo yeWeld ibonisa isigaba se-Ferritic-austenitic Tensile.
Iimicrographs zamehlo ze-E2 electrode welds kwiijiyometri zeweld ezahlukeneyo: (a) I-HAZ ebonisa umgca wokudityaniswa, (b) I-HAZ ebonisa umgca wodibaniso kulwandiso oluphezulu, (c) i-BM yesigaba se-ferritic-austenitic bulk, (d) i-weld geometry , (e) ) ebonisa ummandla wenguqu kummandla, (f) I-HAZ ebonisa inqanaba le-ferritic-austenitic kulwandiso oluphezulu, (g) indawo yokuwelda ebonisa isigaba se-ferritic-austenitic.
Amanani 6a-c kwaye, umzekelo, abonisa ubume bemetallographic ye-DSS joints welded usebenzisa i-electrode ye-E1 kwiijometri ze-welding ezahlukeneyo (Umfanekiso 6d), ebonisa apho ii-micrographs zamehlo zithathwe khona ngokukhuliswa okuhlukeneyo.Kwikhiwane.I-6a, b, f - imimandla yenguqu ye-welded joints, ebonisa isakhiwo sokulingana kwesigaba se-ferrite-austenite.Amanani 7a-c kunye nomzekelo abonisa kwakhona i-OM ye-DSS edibeneyo edibeneyo usebenzisa i-electrode ye-E2 kwiijometri ze-welding ezahlukeneyo (Umfanekiso we-7d), emele iindawo zokuhlalutya kwe-OM kwiindidi ezahlukeneyo.Kwikhiwane.7a,b,f bonisa indawo yotshintsho yejoyini edityanisiweyo kwi-equilibrium ye-ferritic-austenitic.I-OM kwi-welding zone (WZ) iboniswe kwifig.1 kunye nekhiwane.2. I-Welds ye-electrodes E1 kunye ne-E2 6g kunye ne-7g, ngokulandelanayo.I-OM kwi-BM iboniswe kwiMifanekiso 1 kunye ne-2. Kwifig.I-6c, i-e kunye ne-7c, i-e ibonisa imeko ye-welded joints with electrodes E1 kunye ne-E2, ngokulandelanayo.Indawo yokukhanya yinqanaba le-austenite kunye nommandla omnyama omnyama yinqanaba le-ferrite.Ukulingana kwesigaba kwindawo echaphazelekayo ukushisa (i-HAZ) kufuphi nomgca we-fusion ibonise ukubunjwa kwe-Cr2N precipitates, njengoko kuboniswe kwi-micrographs ye-SEM-BSE kwiiFig.8a,b kwaye ingqinwe kwifig.9a,b.Ubukho be-Cr2N buqatshelwe kwisigaba se-ferrite seesampuli kwiiFig.I-8a, b kwaye iqinisekiswe nguhlalutyo lwamanqaku e-SEM-EMF kunye nemizobo yomgca we-EMF yamacandelo adibeneyo (Umfanekiso 9a-b), ngenxa yokushisa okuphezulu kwe-welding.Ukujikeleza kukhawulezisa ukuqaliswa kwe-chromium kunye ne-nitrogen, kuba ubushushu obuphezulu kwi-weld bunyusa i-coefficient yokusasazwa kwe-nitrogen.Ezi ziphumo zixhasa izifundo nguRamirez et al.68 kunye noHerenyu et al.69 ebonisa ukuba, kungakhathaliseki ukuba yintoni umxholo we-nitrogen, i-Cr2N idla ngokufakwa kwiinkozo ze-ferrite, imida yeenkozo, kunye ne-α / \ (\ gamma\) imida, njengoko iphakanyiswe kwakhona. abanye abaphandi.70.71.
(a) uhlalutyo lwe-SEM-EMF yendawo (1, 2 kunye ne-3) yokudibanisa okudibeneyo kunye ne-E2;
I-morphology yomhlaba yeesampuli ezimele kunye nee-EMF zazo ezihambelanayo ziboniswa kwiiFig.10a–c.Kwikhiwane.Amanani 10a kunye ne-10b abonisa i-SEM micrographs kunye ne-EMF yabo ye-spectra ye-welded joints usebenzisa i-electrodes E1 kunye ne-E2 kwindawo ye-welding, ngokulandelanayo, kunye nomkhiwane.I-10c ibonisa i-SEM micrographs kunye ne-EMF spectra ye-OM equlethe i-austenite (\(\ gamma\)) kunye ne-ferrite (\(\ alpha\)) izigaba ngaphandle kweziphi na i-precipitates.Njengoko kuboniswe kwi-spectrum ye-EDS kwi-Fig. 10a, ipesenti ye-Cr (21.69 wt.%) kunye ne-Mo (2.65 wt.%) xa kuthelekiswa ne-6.25 wt.% I-Ni inika ingqiqo yebhalansi ehambelanayo yesigaba se-ferrite-austenitic.I-Microstructure enokunciphisa okuphezulu kumxholo we-chromium (15.97 wt.%) kunye ne-molybdenum (1.06 wt.%) xa kuthelekiswa nomxholo ophezulu we-nickel (10.08 wt.%) kwi-microstructure ye-welded joint ye-electrode E2, eboniswe kuyo ikhiwane.1. Thelekisa.I-spectrum ye-EMF 10b.Imilo ye-acicular ene-fine-grained austenitic structure ebonwe kwi-WZ eboniswe kwifig.I-10b iqinisekisa ukuchithwa okunokwenzeka kwezinto zokufaka i-ferritizing (i-Cr kunye ne-Mo) kwi-weld kunye nemvula ye-chromium nitride (Cr2N) - isigaba se-austenitic.Ukuhanjiswa kweengqungquthela zemvula kunye nemida ye-austenitic (\ (\ gamma \)) kunye ne-ferritic (\ (\ alpha \)) izigaba ze-DSS ezidibeneyo ezidibeneyo ziqinisekisa le nkcazo72,73,74.Oku kubangela ukuba i-corrosion isebenze kakuhle, ekubeni i-Cr ithathwa njengento ephambili yokwenza ifilimu ye-passive ephucula ukuxhatshazwa kwendawo ye-corrosion ye-steel59,75 njengoko kuboniswe kwi-Fig. 10b.Ingabonwa ukuba i-BM kwi-SEM micrograph kwi-Fig. 10c ibonisa ukucocwa okuqinileyo okuziinkozo njengoko iziphumo ze-spectrum ze-EDS zibonisa i-Cr (23.32 wt%), i-Mo (3.33 wt%) kunye ne-Ni (6.32 wt).%) iimpawu ezintle zeekhemikhali.%) njengesixhobo esibalulekileyo sokujonga i-equilibrium microstructure yesigaba se-ferrite-austenitic yesakhiwo se-DSS76.Iziphumo zohlalutyo lwe-spectroscopic ye-EMF ye-welded joints ye-electrode ye-E1 ithethelela ukusetyenziswa kwayo kulwakhiwo kunye neendawo ezinobundlongondlongo, kuba ii-austenite zangaphambili kunye nezizinziso ze-ferrite kwi-microstructure zihambelana nomgangatho we-DSS AISI 220541.72 we-welded joints, i-77.
I-SEM micrographs ye-welding joints, apho (a) i-electrode E1 yendawo ye-welding ine-spectrum ye-EMF, (b) i-electrode E2 yendawo ye-welding ine-EMF spectrum, (c) i-OM ine-EMF spectrum.
Xa kusetyenzwa, kuye kwaphawulwa ukuba iiweldi ze-DSS ziqina kwimowudi ye-ferritic (F-mode), ene-austenite nuclei nucleating engaphantsi kweqondo lobushushu le-ferritic solvus, exhomekeke ikakhulu kwi-chromium ukuya kwi-nickel equivalent ratio (Creq/Nieq) (> I-1.95 iquka imodi ye-F) Abanye abaphandi baye baqaphela le mpembelelo yensimbi ngenxa yesakhono esinamandla sokusabalalisa i-Cr kunye ne-Mo njengezinto ze-ferrite-forming phase8078,79.Kucacile ukuba i-DSS 2205 BM iqulethe inani eliphezulu le-Cr kunye ne-Mo (ebonisa i-Creq ephezulu), kodwa inomxholo ophantsi we-Ni kune-weld kunye ne-E1, i-E2 kunye ne-C electrodes, enegalelo kwi-Creq / Nieq ratio ephezulu.Oku kubonakala kwakhona kuphononongo lwangoku, njengoko kuboniswe kwiThebhile 4, apho umlinganiselo weCreq / Nieq unqunywe kwi-DSS 2205 BM ngaphezu kwe-1.95.Ingabonwa ukuba i-welds kunye ne-electrodes E1, i-E2 kunye ne-C yokuqina kwimodi ye-austenitic-ferritic (imodi ye-AF), imodi ye-austenitic (i-A mode) kunye nemodi ye-ferritic-austenitic, ngokulandelanayo, ngenxa yomxholo ophezulu wemodi yobuninzi (i-FA mode) .), njengoko kuboniswe kwiThebhile 4, umxholo we-Ni, uCr kunye no-Mo kwi-weld ungaphantsi, obonisa ukuba umlinganiselo weCreq / Nieq ungaphantsi kune-BM.I-ferrite ephambili kwi-electrode welds ye-E2 ine-vermicular ferrite morphology kunye ne-Creq / Nieq ratio ezimiseleyo yayiyi-1.20 njengoko ichazwe kwiThebhile 4.
Kwikhiwane.I-11a ibonisa i-Open Circuit Potential (OCP) ngokubhekiselele kwixesha le-AISI DSS 2205 isakhiwo sensimbi kwi-3.5% isisombululo se-NaCl.Ingabonwa ukuba ijika le-ORP litshintshela kwikhono elihle ngakumbi, elibonisa ukubonakala kwefilimu engabonakaliyo kumphezulu wesampulu yesinyithi, ukuhla kwamandla kubonisa ukubola okuqhelekileyo, kunye nokubakho okuqhubekayo ekuhambeni kwexesha kubonisa ukusekwa kwe ifilimu engenzi nto ngokuhamba kwexesha., Umphezulu wesampulu uzinzile kwaye une-Sticky 77. Iigophe zibonisa i-substrates yokulinga phantsi kweemeko ezizinzileyo kuzo zonke iisampuli kwi-electrolyte equlethe i-3.5% yesisombululo se-NaCl, ngaphandle kwesampula 7 (i-weld joint kunye ne-C-electrode), ebonisa ukungazinzi okuncinci.Oku kungazinzi kunokuthelekiswa nobukho be-chloride ion (Cl-) kwisisombululo, esinokukhawulezisa kakhulu ukusabela kwe-corrosion, ngaloo ndlela kwandisa izinga lokubola.Ukuqwalaselwa ngexesha lokuskena kwe-OCP ngaphandle kokusetyenziswa kwamandla kubonise ukuba i-Cl ekuphenduleni inokuchaphazela ukuxhathisa kunye nokuzinza kwe-thermodynamic yeesampuli kwiindawo ezinobundlobongela.UMa et al.81 kunye noLotho et al.I-5 iqinisekise ibango lokuba i-Cl- idlala indima ekukhawuleziseni ukuthotywa kweefilimu ze-passive kwi-substrates, ngaloo ndlela inegalelo ekunxibeleni okungaphezulu.
Uhlalutyo lwe-Electrochemical yeesampuli ezifundwayo: (a) ukuziphendukela kwe-RSD ngokuxhomekeke kwixesha kunye (b) i-potentiodynamic polarization yeesampuli kwi-3.5% isisombululo se-NaCl.
Kwikhiwane.I-11b ibonisa uhlalutyo lokuthelekisa i-potentiodynamic polarization curves (PPC) ye-welded joints of electrodes E1, E2 kunye ne-C phantsi kwefuthe le-3.5% yesisombululo se-NaCl.Iisampuli ze-Welded BM kwi-PPC kunye ne-3.5% isisombululo se-NaCl sibonise ukuziphatha okungahambiyo.Itheyibhile ye-5 ibonisa i-electrochemical analysis parameters of the samples ezifunyenwe kwii-curves ze-PPC, ezifana ne-Ecorr (i-corrosion potential) kunye ne-Epit (i-pitting corrosion potential) kunye nokuphambuka kwazo.Xa kuthelekiswa nezinye iisampuli No. ).Iipropati ezigqithisiweyo eziphezulu zangaphambili xa kuthelekiswa nokugqibela zibangelwa ukulungelelaniswa kokwakheka kwe-microstructural yensimbi (izigaba ze-austenitic kunye ne-ferritic) kunye nokuxinwa kwezinto ezixutywayo.Ngenxa yobukho be-ferrite kunye nezigaba ze-austenitic kwi-microstructure, i-Resendea et al.Abangama-82 baxhasa indlela yokwenziwa kwe-DSS kumajelo osasazo anobundlavini.Ukusebenza okuphantsi kweesampulu ezidityanisiweyo nge-E1 kunye ne-E2 electrode zinokudibaniswa nokuncipha kwezinto eziphambili zokuxutywa, ezifana ne-Cr kunye ne-Mo, kwindawo ye-welding (WZ), ekubeni zizinzisa isigaba se-ferrite (Cr kunye ne-Mo), senze njenge passivators Alloys kwisigaba austenitic of steels oxidized.Impembelelo yezi zinto ekuchaseni imigodi inkulu kwisigaba se-austenitic kunesigaba se-ferritic.Ngenxa yesi sizathu, isigaba se-ferritic sihamba ngokukhawuleza kunesigaba se-austenitic esihambelana nommandla wokuqala wokupasa we-polarization curve.Ezi zinto zinefuthe elibalulekileyo kwi-DSS yokuchasa imingxuma ngenxa yokuchasana kwemigodi ephezulu kwisigaba se-austenitic xa kuthelekiswa nesigaba se-ferritic.Ngoko ke, ukugqithiswa ngokukhawuleza kwesigaba se-ferrite yi-81% ephezulu kunenqanaba le-austenite.Nangona isisombululo se-Cl-in sinesiphumo esibi esinamandla kwisakhono sokudlula kwifilimu yensimbi83.Ngenxa yoko, ukuzinza kwefilimu edlulayo yesampuli kuya kuncitshiswa kakhulu84.Ukusuka kwiTheyibhile.I-6 ibonisa kwakhona ukuba amandla okubola (i-Ecorr) yamalungu adityanisiweyo nge-electrode ye-E1 ayizinzile kancinci kwisisombululo xa kuthelekiswa namalungu adityanisiweyo nge-electrode ye-E2.Oku kuqinisekiswa namaxabiso aphantsi obunzima be-welds usebenzisa i-electrodes E1 kunye ne-E2 kwifig.I-4a, b, ngenxa yomxholo ophantsi we-ferrite (Itheyibhile 5) kunye nomxholo ophantsi we-chromium kunye ne-molybdenum (Itheyibhile 4) kwisakhiwo sensimbi esenziwe.Kunokugqitywa ukuba ukuxhathisa kwe-corrosion ye-steels kwindawo efaniswayo yaselwandle iyanda ngokunciphisa i-welding current kwaye iyancipha ngomxholo ophantsi we-Cr kunye ne-Mo kunye nomxholo ophantsi we-ferrite.Le nkcazo ihambelana nophando olwenziwa nguSalim et al.85 kwimpembelelo yeeparamitha ze-welding ezifana ne-welding current kwi-corrosion integrity of welded steels.Njengoko i-chloride ingena kwintsimbi ngeendlela ezahlukeneyo ezifana nokufunxwa kwe-capillary kunye nokusasazwa, imigodi (i-pitting corrosion) yobunzulu obungalinganiyo kunye nobunzulu yenziwa.Umatshini uhluke kakhulu kwizisombululo eziphezulu ze-pH apho amaqela ajikelezileyo (OH-) atsalwa ngokulula kwindawo yentsimbi, ukuzinzisa ifilimu ye-passive kunye nokubonelela ngokhuseleko olongezelelweyo kwindawo yensimbi25,86.Ukuxhatshazwa kwe-corrosion engcono kakhulu yeesampuli ze-1 kunye neNombolo ye-7 ikakhulu ngenxa yobukho kwisakhiwo sentsimbi yesixa esikhulu se-δ-ferrite (Itheyibhile 5) kunye nenani elikhulu le-Cr kunye ne-Mo (Itheyibhile 4), ekubeni inqanaba le-pitting corrosion likhona ikakhulu kwintsimbi, idityaniswe yindlela ye-DSS, kwisakhiwo sesigaba se-austenitic samacandelo.Ngaloo ndlela, ukubunjwa kweekhemikhali ze-alloy kudlala indima ecacileyo ekusebenzeni kwe-corrosion ye-welded joint87,88.Ukongeza, kuye kwaphawulwa ukuba imizekelo edityanisiweyo kusetyenziswa i-E1 kunye ne-C electrode kolu phononongo ibonise amaxabiso aphantsi e-Ecorr asuka kumagophe e-PPC kunalawo adityanisiweyo kusetyenziswa i-electrode ye-E2 esuka kwi-OCP curves (Itheyibhile 5).Ngoko ke, ummandla we-anode uqala kumandla aphantsi.Olu tshintsho lubangelwa ikakhulu kuzinziso lwenxalenye yomaleko we-passivation owenziwe kumphezulu wesampulu kunye ne-cathodic polarization eyenzeka ngaphambi kokuba uzinzo olupheleleyo lwe-OCP89 luphunyezwe.Kwikhiwane.I-12a kunye ne-b ibonisa imifanekiso ye-3D yeprofayili ye-optical ye-experimental corroded specimens phantsi kweemeko ezahlukeneyo ze-welding.Ingabonwa ukuba ubungakanani be-corrosion ye-pitting ye-specimens buyanda kunye ne-low pitting corrosion potentials eyenziwe yi-welding yangoku ephezulu ye-110 A (Fig. 12b), xa kuthelekiswa nobukhulu bombhobho obufunyenwe kwi-welds kunye nomlinganiselo ophantsi we-welding yangoku. 90 A. (Umfanekiso 12a).Oku kuqinisekisa ibango lika-Mohammed90 lokuba iibhendi ze-slip zenziwe kumphezulu wesampuli ukutshabalalisa ifilimu ye-surface passivation ngokubeka i-substrate kwisisombululo se-3.5% se-NaCl ukwenzela ukuba i-chloride iqale ukuhlasela, ibangele ukuba izinto zichithe.
Uhlalutyo lwe-SEM-EDS kwiThebhile 4 lubonisa ukuba ixabiso le-PREN kwisigaba ngasinye se-austenitic liphezulu kunezo ferrite kuzo zonke ii-welds kunye ne-BM.Ukuqaliswa kwe-pitting kwi-interface ye-ferrite / i-austenite ikhawuleza ukutshatyalaliswa komgangatho wezinto eziphathekayo ngenxa ye-inhomogeneity kunye nokwahlulwa kwezinto ezenzeka kule mimandla91.Ngokungafani nesigaba se-austenitic, apho ixabiso le-pitting resistance elilingana (PRE) liphezulu, ukuqaliswa kwe-pitting kwisigaba se-ferritic kubangelwa ixabiso eliphantsi le-PRE (Itheyibhile 4).Isigaba se-austenite sibonakala siqulethe ixabiso elibalulekileyo le-austenite stabilizer (i-nitrogen solubility), enika ugxininiso oluphezulu lwale nto kwaye, ngoko ke, ukuchasana okuphezulu kwi-pitting92.
Kwikhiwane.Umzobo we-13 ubonisa i-curves ebalulekileyo ye-pitting ye-E1, i-E2, kunye ne-C welds.Ngenxa yokuba ukuxinana kwangoku kunyuke ukuya kwi-100 µA / cm2 ngenxa yokugoba ngexesha lovavanyo lwe-ASTM, kuyacaca ukuba i-@110A weld kunye ne-E1 ibonise ubuncinane be-pitting ubushushu obubalulekileyo be-27.5 ° C elandelwa yi-E2 @ 90A soldering ibonisa i-CPT ye-40 °C, kwaye kwimeko yeC@110A eyona CPT iphezulu yi-41°C.Iziphumo eziphawulweyo zivumelana kakuhle neziphumo eziphawulweyo zovavanyo lwepolarization.
Iimpawu zomatshini kunye nokuziphatha kokubola kwe-duplex yentsimbi yensimbi engenasici zaphandwa kusetyenziswa i-E1 kunye ne-E2 electrode entsha.I-electrode ye-alkaline (E1) kunye ne-acidic electrode (E2) esetyenziswe kwinkqubo ye-SMAW ifakwe ngempumelelo ngokubunjwa kwe-flux kunye nomlinganiselo wokugubungela ngokubanzi we-1.7 mm kunye ne-alkaline index ye-2.40 kunye ne-0.40, ngokulandelanayo.Ukuzinza kwe-thermal ye-fluxes elungiselelwe usebenzisa i-TGA kwindawo engasebenziyo ivavanyiwe.Ubukho bomxholo ophezulu we-TiO2 (%) kwi-matrix ye-flux iphucule ukukhutshwa kwe-slag ye-weldments ye-electrodes ehlanganiswe ne-acidic flux (E2) xa kuthelekiswa ne-electrodes ehlanganiswe ne-flux esisiseko (E1).Nangona i-electrode ezimbini ezigqunyiweyo (i-E1 kunye ne-E2) zinekhono elihle lokuqalisa i-arc.Iimeko ze-Welding, ngokukodwa igalelo lobushushu, i-welding yangoku kunye nesantya, idlala indima ebalulekileyo ekufezekiseni ibhalansi yesigaba se-austenite / ferrite ye-DSS 2205 welds kunye neempawu ezibalaseleyo zomatshini we-weld.Amalungu adityaniswe nge-electrode ye-E1 abonise iimpawu ezibalaseleyo zokuqina (shear 0.2% YS = 497 MPa kunye ne-UTS = 732 MPa), eqinisekisa ukuba i-electrode esisiseko egqunywe nge-flux inesalathisi esiphezulu xa kuthelekiswa ne-acid flux coated electrode.I-Electrodes ibonisa iimpawu ezingcono zoomatshini kunye ne-alkalinity ephantsi.Kucacile ukuba kwiindawo ezidibeneyo ze-electrodes ezine-coating entsha (E1 kunye ne-E2) akukho lungelelaniso lwesigaba se-ferrite-austenitic, esatyhilwa kusetyenziswa i-OES kunye ne-SEM-EDS uhlalutyo lwe-weld kwaye lubalwe ngeqhezu lomthamo i weld.I-Metallography iqinisekise uphononongo lwabo lwe-SEM.microstructures.Oku kubangelwa ikakhulu ngenxa yokutshatyalaliswa kwezinto ezixutywayo ezifana ne-Cr kunye ne-Mo kunye nokukhutshwa okunokwenzeka kwe-Cr2N ngexesha le-welding, eqinisekiswa yi-EDS yokukhangela umgca.Oku kuxhaswa ngakumbi ngamaxabiso obunzima obuphantsi obujongwe kwii-welds kunye ne-E1 kunye ne-E2 electrode ngenxa yomlinganiselo wabo ophantsi we-ferrite kunye ne-alloying element kwisakhiwo sentsimbi.I-Ecorrosion Potential yobungqina (Ecorr) ye-welds usebenzisa i-electrode ye-E1 ibonakalise ukuba ayinyangeki kancinane kwi-corrosion yesisombululo xa kuthelekiswa ne-welds usebenzisa i-electrode ye-E2.Oku kuqinisekisa ukusebenza kakuhle kwee-electrode ezisanda kuphuhliswa kwiiwelds ezivavanywe kwi-3.5% ye-NaCl bume ngaphandle kokubunjwa kwe-alloy mix mix.Kunokugqityezelwa ukuba ukuxhathisa komhlwa kwimekobume yaselwandle eyenziweyo iyenyuka ngokuncipha kombane we-welding.Ngaloo ndlela, imvula ye-carbides kunye ne-nitrides kunye nokunciphisa okulandelayo kwi-corrosion resistance of joints welded usebenzisa i-E1 kunye ne-E2 electrode yachazwa ngokunyuka kwe-welding yangoku, okukhokelela ekungalinganini kwinqanaba le-balance balance of joints welded ukusuka kwi-steel-purpose-purpose steels.
Ngesicelo, idatha yolu phononongo iya kunikwa ngumbhali ochaphazelekayo.
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