Indima yezinto ezisetyenziswa ngokuqhelekileyo kwintsimbi engwevu
I-1.I-Carbon kunye ne-silicon: I-Carbon kunye ne-silicon zizinto ezikhuthaza kakhulu i-graphitization. Ukulingana kwekhabhoni kungasetyenziselwa ukubonisa iziphumo zabo kwisakhiwo se-metallographic kunye neepropathi zomatshini zentsimbi engwevu. Ukwandisa ukulingana kwekhabhoni kubangela ukuba i-graphite flakes ibe rhabaxa, inyuke ngenani, kwaye iyancipha amandla kunye nokuqina. Ngokuchasene noko, ukunciphisa ukulingana kwekhabhoni kunokunciphisa inani leegraphite, ukucokisa igraphite, kunye nokwandisa inani leeprimary austenite dendrites, ngaloo ndlela kuphuculwe iipropathi zoomatshini zentsimbi engwevu. Nangona kunjalo, ukunciphisa ukulingana kwekhabhoni kuya kukhokelela ekunciphiseni ukusebenza kokuphosa.
I-2.I-Manganese: I-Manganese ngokwayo yinto eyenza i-carbides ibambe kwaye ithintele i-graphitization. Inefuthe lokuzinzisa kunye nokucoca i-pearlite kwintsimbi engwevu. Kuluhlu lwe-Mn = 0.5% ukuya kwi-1.0%, ukunyusa umthamo we-manganese kunceda ekuphuculeni amandla kunye nobunzima.
3.I-Phosphorus: Xa umxholo we-phosphorus kwintsimbi etyhidiweyo ungaphezu kwe-0.02%, i-intergranular phosphorus eutectic ingenzeka. I-solubility ye-phosphorus kwi-austenite incinci kakhulu. Xa intsimbi etyhidiweyo iqinile, iphosphorus isala kulwelo. Xa ukuqina kwe-eutectic kuphantse kugqitywe, ukwakheka kwesigaba solwelo esiseleyo phakathi kwamaqela e-eutectic kusondele kukwakheka kwe-eutectic ye-ternary (Fe-2%, C-7%, P). Esi sigaba solwelo siqina malunga ne-955℃. Xa intsimbi etyhidiweyo iqinile, i-molybdenum, i-chromium, i-tungsten kunye ne-vanadium zonke zahlulwa kwisigaba solwelo esityebileyo nge-phosphorus, kwandisa ubuninzi be-phosphorus eutectic. Xa umxholo we-phosphorus kwi-iron cast iphezulu, ngaphezu kwemiphumo eyingozi ye-phosphorus eutectic ngokwayo, iya kunciphisa kwakhona izinto ezixutywayo eziqulethwe kwi-matrix yensimbi, ngaloo ndlela iyancipha umphumo wezinto ezixutywayo. Ulwelo lwe-phosphorus eutectic luyi-mushy malunga neqela le-eutectic eliqina kwaye likhule, kwaye kunzima ukuzaliswa ngexesha lokuqina kokuqina, kwaye ukuphosa kunomkhuba omkhulu wokucutheka.
4.Isulfure: Yehlisa ukumanzi kwentsimbi enyibilikisiweyo kwaye yonyusa ukutyekela kokusahlelwa kokuqhekeka kushushu. Yinto eyingozi kwi-castings. Ngoko ke, abantu abaninzi bacinga ukuba umxholo wesulfure uphantsi, ungcono. Enyanisweni, xa umxholo wesulfure u-≤0.05%, olu hlobo lwentsimbi alusebenzi kwi-inoculant eqhelekileyo esiyisebenzisayo. Isizathu kukuba i-inoculation ibola ngokukhawuleza, kwaye amabala amhlophe ahlala ebonakala kwii-castings.
I-5.I-Copper: I-Copper iyona nto idityanisiweyo yokudibanisa kwimveliso yentsimbi engwevu. Esona sizathu sesokuba ikopolo inendawo esezantsi yokunyibilika (1083℃), kulula ukuyinyibilika, kwaye inesiphumo esihle sokunyibilika. Ikhono le-graphitization lobhedu limalunga ne-1/5 ye-silicon, ngoko inokunciphisa utyekelo lwentsimbi yokuphosa ukuba ne-cast emhlophe. Ngexesha elifanayo, ubhedu lunokunciphisa ubushushu obubalulekileyo benguqu ye-austenite. Ngoko ke, ubhedu lunokukhuthaza ukubunjwa kwe-pearlite, ukwandisa umxholo we-pearlite, kunye nokucoca i-pearlite kunye nokuqinisa i-pearlite kunye ne-ferrite kuyo, ngaloo ndlela kwandisa ubunzima kunye namandla esinyithi. Nangona kunjalo, ubuninzi bobhedu, bungcono. Isixa esifanelekileyo sobhedu esongeziweyo yi-0.2% ukuya kwi-0.4%. Xa ukongeza inani elikhulu lobhedu, ukongeza i-tin kunye ne-chromium ngexesha elifanayo kuyingozi ekusebenzeni kokusika. Kuya kubangela ukuba ubuninzi besakhiwo se-sorbite iveliswe kwisakhiwo se-matrix.
6.I-Chromium: Impembelelo ye-alloying ye-chromium yomelele kakhulu, ngakumbi ngenxa yokuba ukongezwa kwe-chromium kwandisa ukuthambekela kwentsimbi etyhidiweyo ibe nentsimbi emhlophe, kwaye ukuphosa kulula ukushwabana, okukhokelela kwinkunkuma. Ke ngoko, isixa sechromium kufuneka silawulwe. Ngakolunye uhlangothi, kunethemba lokuba intsimbi etyhidiweyo iqulethe inani elithile le-chromium ukuphucula amandla kunye nobunzima bokuphosa; kwelinye icala, i-chromium ilawulwa ngokungqongqo kumda ophantsi ukukhusela ukuphosa ekunciphiseni kwaye kubangele ukwanda kwesantya se-scrap. Amava emveli abamba ukuba xa umxholo we-chromium wentsimbi yokuqala etyhidiweyo idlula i-0.35%, iya kuba nefuthe elibulalayo kwi-casting.
7. I-Molybdenum: I-Molybdenum yinto eqhelekileyo yokwenza i-compound kunye ne-pearlite eyomeleleyo yokuzinza. Iyakwazi ukucokisa igraphite. Xa i-ωMo<0.8%, i-molybdenum inokucoca i-pearlite kwaye iqinise i-ferrite kwi-pearlite, ngaloo ndlela iphucula ngempumelelo amandla kunye nobunzima bentsimbi.
Imiba emininzi kwintsimbi engwevu kufuneka iqatshelwe
I-1.Ukwandisa ukufudumala okanye ukwandisa ixesha lokubamba kunokwenza iinqununu ezikhoyo ezinqabileyo kwi-melt zinyamalale okanye zinciphise ukusebenza kwazo, ukunciphisa inani le-austenite grains.
I-2.I-Titanium inesiphumo sokucokisa i-austenite ephambili kwintsimbi engwevu. Ngenxa yokuba i-titanium carbides, i-nitrides, kunye ne-carbonitrides zinokusebenza njengesiseko se-austenite nucleation. I-Titanium inokunyusa i-core of austenite kwaye icokise iinkozo ze-austenite. Ngakolunye uhlangothi, xa kukho i-Ti engaphezulu kwintsimbi etyhidiweyo, i-S kwintsimbi iya kusabela kunye ne-Ti endaweni ye-Mn ukwenza amasuntswana e-TiS. Undoqo wegraphite weTiS awusebenzi njengalowo weMnS. Ngoko ke, ukubunjwa kwe-eutectic graphite core kulibaziseka, ngaloo ndlela kwandisa ixesha lokunyuka kwe-austenite yokuqala. I-vanadium, i-chromium, i-aluminium, kunye ne-zirconium zifana ne-titanium kuba kulula ukwenza i-carbides, i-nitrides, kunye ne-carbonitrides, kwaye ingaba yi-austenite cores.
3.Kukho umahluko omkhulu kwiziphumo zezitofu ezahlukeneyo kwinani leeutectic clusters, ezicwangciswe ngolu hlobo lulandelayo: CaSi>ZrFeSi>75FeSi>BaSi>SrFeSi. I-FeSi equlethe i-Sr okanye i-Ti inesiphumo esibuthathaka kwinani lamaqela e-eutectic. I-inoculants equlethe imihlaba enqabileyo inesiphumo esihle kakhulu, kwaye umphumo ubaluleke ngakumbi xa udityaniswe ne-Al kunye ne-N. Ferrosilicon equlethe i-Al kunye ne-Bi inokunyusa kakhulu inani lamaqela e-eutectic.
4. Iinkozo zegraphite-austenite zesigaba sesibini sokukhula kwesymbiotic ezenziwe ngeenuclei zegraphite njengeziko zibizwa ngokuba yi-eutectic clusters. I-Submicroscopic graphite aggregates, intsalela ye-graphite particles enganyibilikiyo, amasebe aphambili e-graphite flake, iikhompawundi eziphezulu zokunyibilika kunye nokufakwa kwegesi ekhoyo kwintsimbi etyhidiweyo kwaye inokuba yi-cores ye-eutectic graphite nazo ziyi-cores ze-eutectic clusters. Ekubeni i-eutectic nucleus iyindawo yokuqala yokukhula kwe-eutectic cluster, inani lamaqela e-eutectic libonisa inani leecores ezinokukhula zibe yigraphite kulwelo lwentsimbi ye-eutectic. Izinto ezichaphazela inani lamaqela e-eutectic ziquka ukwakheka kweekhemikhali, imeko engundoqo yentsimbi etyhidiweyo kunye nesantya sokupholisa.
Ubungakanani bekhabhoni kunye ne-silicon ekubunjweni kweekhemikhali kunempembelelo ebalulekileyo. Okukhona ukulingana kwekhabhoni kukufutshane kukwakheka kwe-eutectic, kokukhona amaqela e-eutectic ekhona. I-S yenye into ebalulekileyo echaphazela amaqoqo e-eutectic entsimbi engwevu. Umxholo wesulfure ophantsi awuhambisani nokunyusa amaqoqo e-eutectic, kuba i-sulfide kwintsimbi etyhidiweyo yinto ebalulekileyo ye-graphite core. Ukongezelela, isulfure inokunciphisa amandla okudibanisa phakathi kwe-heterogeneous core kunye ne-melt, ukwenzela ukuba ii-cores ezininzi zisebenze. Xa i-W (S) ingaphantsi kwe-0.03%, inani lamaqela e-eutectic liyancipha kakhulu, kwaye umphumo we-inoculation uyancipha.
Xa i-mass fraction ye-Mn ingaphakathi kwe-2%, isixa se-Mn siyenyuka, kwaye inani lamaqela e-eutectic liyanda ngokufanelekileyo. I-Nb kulula ukuvelisa i-carbon kunye ne-nitrogen compounds kwintsimbi etyhidiweyo, esebenza njenge-graphite core ukwandisa amaqela e-eutectic. I-Ti kunye ne-V inciphisa inani lamaqela e-eutectic ngenxa yokuba i-vanadium inciphisa i-carbon concentration; I-titanium ibamba ngokulula i-S kwi-MnS kunye ne-MgS ukuze yenze i-titanium sulfide, kwaye isakhono sayo se-nucleation asisebenzi njenge-MnS kunye ne-MgS. I-N kwintsimbi etyhidiweyo inyusa inani lamaqela e-eutectic. Xa umxholo we-N ungaphantsi kwe-350 x10-6, awubonakali. Emva kokugqithisa ixabiso elithile, ukunyuka kwe-supercooling kuyanda, ngaloo ndlela kwandisa inani lamaqela e-eutectic. Ioksijini kwintsimbi etyhidiweyo yenza ngokulula ukubandakanywa kwe-oxide ezahlukahlukeneyo njengee-cores, ngoko njengoko i-oksijini isanda, inani lamaqela e-eutectic liyakhula. Ukongeza kwi-chemical composition, i-core state ye-eutectic melt yinto ebalulekileyo enempembelelo. Ukugcina ubushushu obuphezulu kunye nokushisa ixesha elide kuya kubangela ukuba isiseko sokuqala sinyamalale okanye sinciphise, sinciphise inani lamaqela e-eutectic, kunye nokwandisa ububanzi. Ukunyangwa kwe-inoculation kunokuphucula kakhulu imeko engundoqo kunye nokwandisa inani lamaqela e-eutectic. Izinga lokupholisa linesiphumo esicacileyo kakhulu kwinani lamaqela e-eutectic. Okukhona ukupholisa ngokukhawuleza, kokukhona kubakho amaqela eeutectic.
5.Inani lamaqela e-eutectic libonisa ngokuthe ngqo ubukhulu beenkozo ze-eutectic. Ngokubanzi, iinkozo ezintle zinokuphucula ukusebenza kwesinyithi. Ngaphantsi kwesiseko sokwakheka kweekhemikhali ezifanayo kunye nohlobo lwegraphite, njengoko inani lamaqela e-eutectic likhula, amandla e-tensile ayanda, ngenxa yokuba amaphepha e-graphite kumaqela e-eutectic ahamba kakuhle njengoko inani lamaqela e-eutectic likhula, okwandisa amandla. Nangona kunjalo, ngokunyuka komxholo we-silicon, inani lamaqela e-eutectic landa kakhulu, kodwa amandla ayancipha endaweni yoko; amandla entsimbi yokuphosa ayanda ngokunyuka kobushushu obuphezulu (ukuya kwi-1500 ℃), kodwa ngeli xesha, inani lamaqela e-eutectic liyancipha kakhulu. Ubudlelwane phakathi komthetho wotshintsho lwenani lamaqela e-eutectic abangelwa unyango lwe-inoculation lwexesha elide kunye nokunyuka kwamandla akusoloko kunendlela efanayo. Amandla afunyenwe ngonyango lwe-inoculation kunye ne-FeSi equkethe i-Si kunye ne-Ba iphezulu kunokuba ifunyenwe nge-CaSi, kodwa inani lamaqela e-eutectic e-iron cast lincinci kakhulu kuneCaSi. Ngokunyuka kwenani lamaqela e-eutectic, ukuthambekela kwe-shrinkage ye-iron cast iyanda. Ukuze kuthintelwe ukubunjwa kwe-shrinkage kwiindawo ezincinci, inani lamaqela e-eutectic kufuneka lilawulwe ngaphantsi kwe-300 ~ 400 / cm2.
6. Ukongeza izinto ze-alloy (Cr, Mn, Mo, Mg, Ti, Ce, Sb) ezikhuthaza i-supercooling kwi-inoculants ye-graphitized inokuphucula iqondo le-supercooling ye-iron cast, ihlambulule iinkozo, inyuse inani le-austenite kwaye ikhuthaze ukubunjwa ipearlite. Izinto ezongezelelweyo ezisebenzayo (Te, Bi, 5b) zinokubhengezwa kumphezulu we-nuclei yegraphite ukunciphisa ukukhula kwegraphite kunye nokunciphisa ubungakanani begraphite, ukuze kuphunyezwe injongo yokuphucula iimpawu zomatshini ezibanzi, ukuphucula ukufana, kunye nokwandisa umgaqo wombutho. Lo mgaqo usetyenziswe kwimveliso yentsimbi ephezulu ye-carbon cast (njengama-brake parts).
Ixesha lokuposa: Jun-05-2024
