Zipangizo zopangira zinthu zapamwamba kwambiri ndiye maziko opangira zomangira zapamwamba kwambiri. Komabe, zinthu zambiri za opanga zomangira zimakhala ndi ming'alu. Nchifukwa chiyani izi zimachitika?

Pakadali pano, zomwe zimafotokozedwa bwino za ndodo za waya zachitsulo zopangidwa ndi kaboni zomwe zimaperekedwa ndi opanga zitsulo zapakhomo ndi φ 5.5-φ 45, ndipo kukula kwake ndi φ 6.5-φ 30. Pali ngozi zambiri zabwino zomwe zimachitika chifukwa cha kugawanika kwa phosphorous, monga kugawanika kwa phosphorous kwa ndodo yaying'ono ya waya ndi mipiringidzo. Mphamvu ya kugawanika kwa phosphorous ndi kusanthula kwa ming'alu zafotokozedwa pansipa kuti zigwiritsidwe ntchito. Kuwonjezeredwa kwa phosphorous mu chithunzi cha gawo la kaboni yachitsulo kudzatseka gawo la austenite mofananamo ndikuwonjezera mtunda pakati pa solidus ndi liquidus. Pamene chitsulo chokhala ndi phosphorous chazimitsidwa kuchokera kumadzi kupita ku cholimba, chiyenera kudutsa kutentha kwakukulu.

Kufalikira kwa phosphorous mu chitsulo kumakhala pang'onopang'ono, ndipo chitsulo chosungunuka chokhala ndi phosphorous yambiri (malo otsika osungunuka) chimadzaza ndi ma dendrite oyamba olimba, zomwe zimapangitsa kuti phosphorous igawanike. Pazinthu zomwe nthawi zambiri zimakhala ndi ming'alu panthawi yozizira kapena kutulutsa kozizira, kufufuza ndi kusanthula kwa metallographic kukuwonetsa kuti ferrite ndi pearlite zimagawidwa m'mizere, ndipo pali ferrite yoyera yokhala ndi mipanda mu matrix. Pali malo ophatikizira a sulfide yopepuka pang'ono pa matrix ya ferrite yokhala ndi mipanda. Kapangidwe ka mipanda ka sulfide kamatchedwa "mzere wa mzimu" chifukwa cha kusiyana kwa sulfide.
Chifukwa chake n'chakuti dera lomwe lili ndi phosphorous yoopsa limapereka malo oyera owala m'dera lowonjezera phosphorous. Mu slab yopangira mosalekeza, chifukwa cha kuchuluka kwa phosphorous m'dera loyera, makristalo okhala ndi columnar okhala ndi phosphorous concentrate, zomwe zimachepetsa kuchuluka kwa phosphorous. Pamene billet imauma, austenite dendrites amayamba kulekanitsidwa ndi chitsulo chosungunuka. Phosphorus ndi sulfure m'ma dendrites awa amachepa, koma chitsulo chosungunuka cholimba chimakhala ndi zinthu za phosphorous ndi sulfure. Chimauma pakati pa nkhwangwa za dendrite chifukwa zinthu za phosphorous ndi sulfure zimakhala zambiri. Panthawiyi, sulfide imapangidwa, ndipo phosphorous imasungunuka mu matrix. Chifukwa zinthu za phosphorous ndi sulfure zimakhala zambiri, sulfide imapangidwa pano, ndipo phosphorous imasungunuka mu matrix. Chifukwa cha kuchuluka kwa zinthu za phosphorous ndi sulfure, kuchuluka kwa carbon mu phosphorous solid solution kumakhala kwakukulu. Kumbali zonse ziwiri za lamba wa carbonaceous, ndiko kuti, mbali zonse ziwiri za dera lowonjezera phosphorous, lamba wautali komanso wopapatiza wa pearlite wofanana ndi lamba woyera wa ferrite umapangidwa, ndipo minofu yoyandikana nayo imalekanitsidwa. Pansi pa kupanikizika kwa kutentha, billet idzafika ku njira yopangira pakati pa mipata, chifukwa lamba wa ferrite uli ndi phosphorous yambiri, ndiko kuti, kugawikana kwa phosphorous kudzatsogolera ku kupangidwa kwa kapangidwe ka lamba wowala kwambiri wa ferrite wokhala ndi kapangidwe ka lamba wowala kwambiri wa ferrite. Zitha kuwoneka kuti palinso mikwingwirima yopepuka ya sulfide mu lamba wowala kwambiri wa ferrite, womwe umagawidwa ndi mzere wautali wa lamba wolemera wa phosphorous ferrite, womwe nthawi zambiri timautcha "mzere wa mzimu". (Onani Chithunzi 1-2)

Mzere wa Flange

Mu ndondomeko yotentha yozungulira, bola ngati pali kugawanika kwa phosphorous, sizingatheke kupeza kapangidwe ka microstructure kofanana. Chofunika kwambiri, chifukwa kugawanika kwa phosphorous kwapanga kapangidwe ka "mzere wa mzimu", kudzachepetsa mphamvu za makina a chinthucho. Kugawanika kwa phosphorous mu chitsulo cholumikizidwa ndi kaboni ndikofala, koma kuchuluka kwake ndi kosiyana. Kugawanika kwa phosphorous kwambiri ("mzere wa mzimu") kumabweretsa zotsatirapo zoyipa kwambiri pa chitsulo. Mwachionekere, kugawanika kwakukulu kwa phosphorous ndiko chifukwa cha kusweka kwa mutu wozizira. Chifukwa kuchuluka kwa phosphorous m'zitsulo zosiyanasiyana ndi kosiyana, zinthuzo zimakhala ndi mphamvu ndi kuuma kosiyana. Kumbali inayi, zimapangitsa kuti zinthuzo zipange kupsinjika kwamkati, komwe kungapangitse kuti zinthuzo zikhale zosavuta kusweka. Mu zinthu zomwe zili ndi kapangidwe ka "mzere wa mzimu", ndi chifukwa cha kuchepa kwa kuuma, mphamvu, kutalika pambuyo pa kusweka ndi kuchepa kwa malo, makamaka kuchepa kwa kulimba kwa impact, kuti kuchuluka kwa phosphorous m'zinthuzo kuli ndi ubale wabwino ndi kapangidwe ndi katundu wa chitsulo.
Mu minofu ya "mzimu" yomwe ili pakati pa munda wa masomphenya, kuchuluka kwakukulu kwa sulfide yopyapyala, yopepuka ya imvi kunapezeka pogwiritsa ntchito metallography. Zosakaniza zopanda zitsulo zomwe zili mu chitsulo chomangidwa zimapezeka makamaka mu mawonekedwe a ma oxide ndi ma sulfide. Malinga ndi GB/T10561-2005 Standard Classification Diagram ya Zomwe Zili mu Zosakaniza Zopanda zitsulo mu Chitsulo, kuchuluka kwa sulfide komwe kuli mu Class B inclusions ndi 2.5 kapena kupitirira apo. Zosakaniza zopanda zitsulo ndi gwero lotha ming'alu. Kukhalapo kwake kudzawononga kwambiri kupitiriza ndi kupangika kwa chitsulo, motero kuchepetsa kwambiri mphamvu ya pakati pa tinthu tating'onoting'ono.
Akuti sulfide yomwe ili mkati mwa kapangidwe kake ka "mzere wa mzimu" wa chitsulo ndiye gawo losavuta kusweka. Chifukwa chake, zomangira zambiri zinasweka mu kuzizira ndi kuzizira kwa kutentha pamalo opangira, zomwe zinayambitsidwa ndi kuchuluka kwa ma sulfide ataliatali a imvi. Nsalu yosalukidwa iyi inawononga kupitiriza kwa zinthu zachitsulo ndikuwonjezera chiopsezo cha kutentha. "Mzere wa mzimu" sungachotsedwe mwa kusinthasintha ndi njira zina, ndipo zinthu zodetsa ziyenera kulamulidwa mosamala musanasungunuke kapena zopangira zilowe mu chomera. Malinga ndi kapangidwe ndi kusokonekera, zinthu zopanda chitsulo zimagawidwa mu alumina (mtundu A) silicate (mtundu C) ndi spherical oxide (mtundu D). Mawonekedwe ake adzadula kupitiriza kwa chitsulocho ndikukhala mabowo kapena ming'alu pambuyo pochotsa, zomwe zimakhala zosavuta kupanga ming'alu panthawi yozizira ndikupangitsa kuti kupsinjika kukhalepo panthawi yotenthetsera, zomwe zimapangitsa kuti ming'alu izitha. Chifukwa chake, zinthu zopanda chitsulo ziyenera kulamulidwa mosamala. Ma Structural Carbon Structural Steels GB/T700-2006 ndi GB T699-2016 High Quality Carbon Steels akupereka zofunikira pa zinthu zomwe sizili zachitsulo. Pazinthu zofunika, nthawi zambiri zimakhala A, B, C, fine series, fine series siziposa 1.5, D, Ds, ndipo level 2 siziposa level 2.

Kampani ya Hebei Chengyi Engineering Materials Co., Ltd. ndi kampani yomwe yakhala ikugwira ntchito yopanga ndi kugulitsa zinthu zomangira kwa zaka 21. Zomangira zathu zimagwiritsa ntchito zipangizo zopangira zapamwamba kwambiri, ukadaulo wapamwamba wopanga ndi kupanga zinthu, komanso njira yabwino yoyendetsera zinthu kuti zitsimikizire kuti zinthu zili bwino. Ngati mukufuna kugula zomangira, chonde titumizireni uthenga.