Chitsulo chosapanga dzimbiri chotchedwa Ferritic chimatanthawuza chitsulo chosapanga dzimbiri chokhala ndi thupi la cubic ferrite ngati mawonekedwe a matrix pa kutentha kwambiri komanso kutentha kwabwinobwino. Chitsulo chosapanga dzimbiri cha Ferritic chili ndi chitsulo ndi chromium monga zinthu zazikulu, nthawi zambiri sizikhala ndi faifi tambala, ndipo zina zimakhala ndi molybdenum, titaniyamu kapena niobium pang'ono ndi zinthu zina. Ili ndi kukana kwa okosijeni kwabwino, kukana kwa dzimbiri komanso kukana kwa chloride corrosion cracking. Kuphatikiza apo, chitsulo chosapanga dzimbiri cha ferritic chimakhalanso ndi mawonekedwe amphamvu yamatenthedwe, kukulitsa kocheperako pang'ono, kukana bwino kwa okosijeni, komanso kukana kwamphamvu kwa dzimbiri. Amagwiritsidwa ntchito kwambiri popanga zinthu zomwe zimalimbana ndi mlengalenga, nthunzi yamadzi, madzi, ndi oxidative acid corrosion. Oyimilira zitsulo zosapanga dzimbiri za ferritic ndi: AISI 410 (UNS S41000), AISI 420 (UNS S42000), AISI 430 (UNS S43000) malinga ndi ASTM; 1.4006, 1.4021, 1.4016, malinga ndi muyezo wa EN ... etc.
Chitsulo chosapanga dzimbiri cha Ferritic chitha kugawidwa kukhala chromium yochepa, chromium yapakatikati ndi chromium yayikulu malinga ndi zomwe zili mu chromium. Malinga ndi chiyero cha chitsulo, makamaka zomwe zili mu carbon ndi nitrogen zonyansa, zimatha kugawidwa muzitsulo zosapanga dzimbiri za ferritic ndi chitsulo chosapanga dzimbiri cha ferritic. Chitsulo chosapanga dzimbiri chosapanga dzimbiri cha ferritic chimakhala ndi zovuta za kutentha pang'ono komanso kutentha kwachipinda, kukhudzika kwa notch, chizolowezi chambiri chambiri chambiri, komanso kusawotcherera bwino. Ngakhale kuti chitsulo chamtunduwu chinapangidwa kale, ntchito yake ya mafakitale yakhala yoletsedwa kwambiri. Zofooka zazitsulo zosapanga dzimbiri zosapanga dzimbiri za ferritic zimagwirizana ndi chiyero cha chitsulocho, makamaka zomwe zili pamwamba pa zinthu zapakati monga carbon ndi nitrogen muzitsulo. Malingana ngati mpweya ndi nayitrogeni muzitsulo ndizochepa mokwanira, zofooka zomwe zili pamwambazi zikhoza kugonjetsedwa.
Poyerekeza ndichitsulo chosapanga dzimbiri cha austenitic, chitsulo chosapanga dzimbiri cha ferritic chimakhala ndi kukana bwino kwa dzimbiri, kukana kutentha komanso kutheka. Popeza gawo la ferrite silingathe kusungunula kaboni, ferrite ili ndi mawonekedwe ofewa komanso osavuta kupunduka. Monga chitsulo chosapanga dzimbiri cha martensitic, popeza kapangidwe ka lattice ndi kapangidwe ka cubic pakati pa thupi, ndi paramagnetic, motero chitsulo chosapanga dzimbiri cha ferritic ndi maginito. Chitsulo chosapanga dzimbiri cha Austenitic sichikhala ndi maginito chifukwa cha mawonekedwe ake apakati pankhope.
Mtengo wa chitsulo chosapanga dzimbiri cha ferritic sikuti ndi wochepa komanso wokhazikika, komanso uli ndi zinthu zambiri zapadera ndi ubwino. Zatsimikiziridwa kuti chitsulo chosapanga dzimbiri cha ferritic ndi njira yabwino kwambiri.
Chitsulo chosapanga dzimbiri cha ferritic
Zitsulo zoterezi zimaphatikizapo zinthu zochepa, zapakatikati komanso zapamwamba za chromium. Chitsulo chosapanga dzimbiri cha chromium ferritic chili ndi pafupifupi 11% mpaka 14% chromium, monga 00Cr12 ndi 0Cr13Al ku China. American AISI 400, 405, 406MF-2. Chitsulo chamtunduwu chimakhala ndi kulimba bwino, pulasitiki, mapindikidwe ozizira komanso kuwotcherera. Chifukwa chitsulo chimakhala ndi kuchuluka kwa chromium ndi aluminiyamu, chimakhala ndi kukana kwa okosijeni komanso kukana dzimbiri. 405 angagwiritsidwe ntchito ngati nsanja kuyenga mafuta, thanki akalowa, nthunzi chopangira magetsi tsamba, kutentha sulfure dzimbiri zosagwira chipangizo, etc. 400 zipangizo zapakhomo ndi ofesi, etc. 409 ntchito galimoto utsi muffler dongosolo zipangizo ndi mipope ozizira ndi madzi otentha etc. Medium chromium ferritic chitsulo chosapanga dzimbiri, zomwe zili mu chromium ndi 14% mpaka 19%, monga 1Cr17 ndi 1Cr17Mo ku China. AISI 429, AISI 430, AISI 433, AISI 434, AISI 435, AISI 436, AISI 439 ku United States. Chitsulo chamtunduwu chimakhala ndi dzimbiri komanso kukana kwa dzimbiri. Ntchito yake yowumitsa coefficient ndi yaying'ono (n≈2), ndipo imakhala ndi zojambula zakuya zabwino, koma ductility yake ndiyabwino. AISI 430 ferritic zitsulo zosapanga dzimbiri zimagwiritsidwa ntchito kukongoletsa zomangamanga, zokongoletsera zamagalimoto, zida za khitchini, zoyatsira gasi ndi zida za mafakitale a nitric acid, etc. AISI 434 imagwiritsidwa ntchito kukongoletsa kunja kwa magalimoto ndi nyumba. 439 imagwiritsidwa ntchito ngati payipi yamagetsi otenthetsera madzi, mapaipi a malasha ndi gasi, etc. High chromium ferritic chitsulo chosapanga dzimbiri chili ndi 19% mpaka 30% chromium, monga Cr18Si2 ndi Cr25 ku China, AISI 442, AISI 443 ndi AISI 446 ku United States. Mayiko. Zitsulo zoterezi zimakhala ndi kukana kwa okosijeni wabwino. AISI 442 imagwiritsidwa ntchito mosalekeza mumlengalenga, kutentha kwapamwamba ndi 1035 ° C, ndipo kutentha kwakukulu kuti mugwiritse ntchito mosalekeza ndi 980 ° C. AISI 446 ferritic chitsulo chosapanga dzimbiri chili ndi kukana bwino kwa okosijeni.
Mpweya wosapanga dzimbiri wa ferriticl
Chitsulo chamtunduwu chimakhala ndi mpweya wochepa kwambiri, nayitrogeni; mkulu chromium, molybdenum, titaniyamu, niobium ndi zinthu zina. Monga China 00Cr17Mo, 00Cr18Mo2, 00Cr26Mol, 00Cr30Mo2. Chitsulo chamtunduwu chimakhala ndi zida zabwino zamakina (makamaka kulimba), weldability, intergranular corrosion resistance, pitting corrosion resistance, corrosion resistance resistance, komanso kupsinjika bwino kwa dzimbiri. Mwachitsanzo, 18-2 ferritic chitsulo chosapanga dzimbiri chimakhala ndi kukana kwa dzimbiri mu nitric acid, acetic acid, NaOH, kukana kwa dzimbiri mu 3% NaCl ndi FeCl3 ndikofanana kapena kupitilira 18-8 austenitic chitsulo chosapanga dzimbiri, 26CrMo chitsulo mu media zambiri kukana Corrosion , makamaka mu ma organic acid, ma oxidizing acid, ndi ma alkali amphamvu. Ili ndi kukana kwa dzimbiri kwa pitting mukatikati mwamphamvu ya chloride. Palibe kupsinjika kwa dzimbiri kusweka kumachitika mu chloride, hydrogen sulfide, sulfuric acid wambiri ndi alkali wamphamvu. 30Cr-2Mo ili ndi kukana kwakukulu kwa kuyika kwa dzimbiri ndi kuphulika kwa ming'alu ndikusunga kupsinjika kwa dzimbiri.
Kukana kwa dzimbiri kwa ferritic chitsulo chosapanga dzimbiri
(1) Kudzimbirira kofanana.
Chromium ndiye chinthu chosavuta kuchita. M'malo amlengalenga, aloyi ya iron-chromium yokhala ndi chromium yopitilira 12% imatha kudzipangira yokha. Mu oxidizing sing'anga, zomwe zili mu chromium zitha kuchepetsedwa ngati zikupitilira 17%. Muzinthu zina zowononga, chromium yapamwamba ndi molybdenum, faife tambala, mkuwa ndi zinthu zina zitha kuwonjezeredwa kuti mupeze kukana kwa dzimbiri.
(2) Intergranular dzimbiri.
Zitsulo zosapanga dzimbiri za ferritic, monga zitsulo zosapanga dzimbiri za austenitic, zimavutika ndi dzimbiri, koma chithandizo cholimbikitsa komanso kutentha kuti mupewe dzimbiri ndi zosiyana. Chitsulo chosapanga dzimbiri cha Ferritic chimakonda kuphulika kwa intergranular kuchokera ku kuzizira kofulumira pamwamba pa 925 ° C, ndipo dziko (boma lodziwitsidwa) lomwe lingathe kuwononga intergranular likhoza kuthetsedwa pakapita nthawi yochepa kutentha kwa 650-815 ° C. Kuwonongeka kwa intergranular kwa chitsulo cha ferritic kumakhalanso chifukwa cha kuchepa kwa chromium chifukwa cha mpweya wa carbide. Chifukwa chake, kuchepetsa zomwe zili mu kaboni ndi nayitrogeni muzitsulo ndikuwonjezera zinthu monga titaniyamu ndi niobium zitha kuchepetsa kutengeka kwa dzimbiri la intergranular.
(3) Kuboola ndi dzimbiri m’ming’alu.
Chromium ndi molybdenum ndi zinthu zothandiza kwambiri kupititsa patsogolo kukana kwa chitsulo chosapanga dzimbiri komanso kupindika kwa ming'alu. Pamene zinthu za chromium zikuchulukirachulukira, zomwe zili mu chromium mufilimu ya okusayidi zimachulukanso, ndipo kukhazikika kwa mankhwala a filimuyo kumawonjezeka. Molybdenum ndi adsorbed pa yogwira zitsulo pamwamba mu mawonekedwe a MoO4, amene linalake ndipo tikulephera Kutha kwa zitsulo, kulimbikitsa repassivation, ndi kuteteza kuwonongeka kwa filimu. Chifukwa chake, chitsulo chosapanga dzimbiri cha chromium ndi molybdenum ferritic chimakhala cholimba kwambiri polimbana ndi dzimbiri komanso dzimbiri.
(4) Kukaniza kupsinjika kwa corrosion cracking.
Chifukwa cha mawonekedwe a bungwe, chitsulo chosapanga dzimbiri cha ferritic sichikhala ndi dzimbiri pakati pomwe zitsulo zosapanga dzimbiri za austenitic zimapanga kusweka kwa corrosion.
Makina opangira chitsulo chosapanga dzimbiri cha ferritic
Chitsulo chosapanga dzimbiri cha Ferritic sichingalimbitsidwe ndi chithandizo cha kutentha chifukwa palibe kusintha kwa gawo. Nthawi zambiri, imagwiritsidwa ntchito pambuyo pa annealing pa 700-800 ° C. Chifukwa cha kukula kwa atomiki yachitsulo ndi chromium, njira yolimba yolimbikitsira ndi yaying'ono, mphamvu zokolola ndi mphamvu zowonongeka zazitsulo zosapanga dzimbiri za ferritic ndizokwera pang'ono kuposa zachitsulo chochepa cha carbon, ndipo ductility ndi yotsika kuposa ya chitsulo chochepa cha carbon. .
1) Chipinda kutentha brittleness wa wamba ferritic chitsulo chosapanga dzimbiri.
Chitsulo chosapanga dzimbiri chosapanga dzimbiri chodziwika bwino chimakhudzidwa ndi notche, ndipo kutentha kwa brittle kusintha kumakhala pamwamba pa kutentha kwa chipinda kupatula chitsulo chosapanga dzimbiri cha chromium ferritic. Kuchuluka kwa chromium, kumapangitsanso kuzizira kwambiri. Kuzizira kozizira kumeneku kumagwirizana ndi zinthu zapakati monga mpweya ndi nayitrogeni muzitsulo, ndipo chitsulo cha ultra-pure ferritic chimakhala ndi mpweya wochepa kwambiri muzinthu zapakati monga carbon ndi nitrogen, kotero zimatha kupeza kulimba kwabwino, ndi kusintha kwamphamvu. kutentha kumatha kutsika pansi pa kutentha kwa chipinda.
2) High kutentha embrittlement wamba ferritic zitsulo zosapanga dzimbiri.
Chitsulo chosapanga dzimbiri cha ferritic chimatenthedwa kufika pamwamba pa 927 ° C ndiyeno chimakhazikika mwachangu mpaka kutentha, pulasitiki ndi kulimba zimachepetsedwa kwambiri. Kutentha kwapamwamba kumeneku kumakhudzana ndi mpweya wothamanga wa carbon (nitride) pamalire a tirigu kapena kusuntha pa kutentha kwa 427-927 ° C. Kuchepetsa kaboni ndi nayitrogeni muzitsulo (pogwiritsa ntchito ukadaulo wa Ultra-pure) kumatha kusintha kwambiri kuphulika uku. Kuonjezera apo, chitsulo cha ferritic chikatenthedwa pamwamba pa 927 ° C, mphamvu ya tirigu idzaphwanyidwa, ndipo njere zowonongeka zidzasokoneza pulasitiki ndi kulimba kwachitsulo.
3) Kupanga kwa σ-phase.
Malinga ndi chithunzi cha iron-chromium, chikasungidwa pa 500-800 ° C, aloyi yomwe ili ndi 40% -50% chromium ipanga gawo limodzi σ, ndipo aloyi yomwe ili ndi chromium yosakwana 20% kapena kupitilira 70% ipanga. dongosolo la α+σ la magawo awiri. Mapangidwe a σ-gawo adzachepetsa kwambiri ductility ndi kulimba kwachitsulo. Chifukwa chake, chitsulo chosapanga dzimbiri cha ferritic sichiyenera kugwiritsidwa ntchito kwa nthawi yayitali pa 500-800 ° C.
4) Kuwonongeka kwa 475 ° C.
Chitsulo chokwera kwambiri cha chromium (> 15%) chimapangidwa mwamphamvu chikasungidwa pa 400-500 °C. Mtundu uwu wa embrittlement umatenga nthawi yayifupi kuposa mvula ya σ. Mwachitsanzo, pamene 0.080C-0.4Si-16.9Cr chitsulo chosapanga dzimbiri chimasungidwa pa 450 ° C kwa maola 4, kulimba kwa kutentha kwa chipinda kumatsika mpaka ziro. Kuchuluka kwa embrittlement kumawonjezeka ndi kuchuluka kwa chromium, koma kulimbako kumatha kuchira pambuyo pa chithandizo chapamwamba cha 600 ° C. Kukhazikika pa 475 ° C ndi chifukwa cha mvula ya gawo la alpha lolemera ndi chromium. Chitsulo choterocho chiyenera kupewa kutentha pafupi ndi 475 ° C.
Nthawi yotumiza: May-02-2023