Jula i-ayiniliqela le-iron-carbon alloys kunye nomxholo wekhabhoni omkhulu kune-2%.Ukusebenziseka kwayo kuvela kubushushu obuphantsi bokunyibilika kwayo.Izinto zealloyi ziyawuchaphazela umbala wayo xa wophukile: intsimbi emhlophe etyhidiweyo inobumdaka bekhabhide obuvumela iintanda ukuba zidlule ngokuthe ngqo, intsimbi engwevu inamacangca egraphite ajikisa ukuqhekeka okudlulayo kwaye aqalise ukuqhekeka okutsha okungenakubalwa njengoko kuqhekeka imathiriyeli, kwaye intsimbi etyhidiweyo inesangqa. igraphite "nodules" ethintela ukuqhekeka ukuba kuqhubele phambili.

I-Carbon (C) ukusuka kwi-1.8 ukuya kwi-4 wt%, kunye ne-silicon (Si) i-1-3 wt%, zizinto eziphambili zokudibanisa isinyithi.I-iron alloys kunye nomxholo ophantsi wekhabhoni zaziwa ngokuba yintsimbi.

Intsimbi etyhidiweyo ithande ukuba brittle, ngaphandle kweentsimbi ezithambileyo.Ngomlinganiselo wayo ophantsi wokunyibilika, u-fluidity olungileyo, u-castability, ubugcisa obugqwesileyo, ukuchasana nokuguqulwa kunye nokumelana nokunxiba, iintsimbi eziphonsiweyo ziye zaba yinto yobunjineli enoluhlu olubanzi lwezicelo kwaye zisetyenziswa kwimibhobho, oomatshini kunye namacandelo oshishino lweemoto, njenge-cylinder. iintloko, iibhloko zesilinda kunye neekesi zebhokisi yegiya.Iyakwazi ukumelana nomonakalo nge-oxidation.

Izinto zakudala ezenziwe ngentsimbi ziqala ngenkulungwane ye-5 BC, kwaye zafunyanwa ngabembi bezinto zakudala kwindawo ngoku ebizwa ngokuba yiJiangsu eTshayina.Intsimbi yentsimbi yayisetyenziswa kwiChina yakudala ukulwa, ezolimo, kunye nokwakha.Ngenkulungwane ye-15, intsimbi etyhidiweyo yasetyenziselwa iinkanunu eBurgundy, eFransi, naseNgilani ngexesha loHlaziyo.Izixa zentsimbi ezisetyenziselwa inkanunu zazifuna imveliso yomlinganiselo omkhulu.Ibhulorho yokuqala yokutyhilwa yentsimbi yakhiwa ngeminyaka yoo-1770 ngu-Abraham Darby III, kwaye yaziwa ngokuba yi-Iron Bridge eShropshire, eNgilani.Kwakhona kwasetyenziswa isinyithi esakhiweyo ekwakhiweni kwezakhiwo.

Izinto zokudibanisa

Iimpawu zentsimbi yokuphosa zitshintshwa ngokongeza izinto ezahlukeneyo zokuhlanganisa, okanye ialloyants.Ecaleni kwekhabhoni, isilicon yeyona nto ibalulekileyo kuba inyanzela ikhabhoni ukuba iphume kwisisombululo.Ipesenti ephantsi ye-silicon ivumela i-carbon ukuba ihlale kwisisombululo esenza i-iron carbide kunye nokuveliswa kwentsimbi emhlophe.Ipesenti ephezulu yesilicon inyanzela ikhabhoni ngaphandle kwesisombululo senza igraphite kunye nokuveliswa kwentsimbi engwevu.Ezinye i-alloying agents, i-manganese, i-chromium, i-molybdenum, i-titanium kunye ne-vanadium iphikisana ne-silicon, ikhuthaza ukugcinwa kwekhabhoni, kunye nokubunjwa kwaloo carbides.I-nickel kunye ne-copper yandisa amandla, kunye ne-machinability, kodwa ungatshintshi inani legraphite eyenziwe.Ikhabhoni ekwimo yegraphite iphumela kwintsimbi ethambileyo, inciphisa ukushwabana, ithobe amandla, kwaye icuthe ukuxinana.I-Sulfur, ubukhulu becala ingcoliseko xa ikhona, yenza i-iron sulfide, ethintela ukubunjwa kwegraphite kwaye yandisa ubulukhuni.Ingxaki ngesulfure kukuba yenza i-viscous yentsimbi etyhidiweyo, ebangela iziphene.Ukuchasana neziphumo zesulfure, i-manganese yongezwa kuba ezimbini zenza i-manganese sulfide endaweni ye-iron sulfide.Imanganese sulfide ikhaphukhaphu kunenyibiliko, ngoko ithande ukudada iphuma kwinyibilika iye kwi-slag.Ubungakanani bemanganese efunekayo ukuze i-neutralize isulfure yi-1.7 × umxholo wesulfure + 0.3%.Ukuba ngaphezu kwesi sixa se-manganese songezwa, ngoko ke iifom ze-manganese ze-carbide, ezandisa ubunzima kunye nokuqhaqhaqhaza, ngaphandle kwesinyithi esimpunga, apho ukuya kwi-1% ye-manganese yandisa amandla kunye noxinaniso.

I-Nickel yenye yezona zinto zixhaphakileyo zokudibanisa kuba icokisa i-pearlite kunye nesakhiwo segraphite, iphucula ukuqina, kwaye idibanisa ubunzima phakathi kobunzima becandelo.I-Chromium yongezwa ngamanani amancinci ukunciphisa igraphite yamahhala, ivelise i-chill, kwaye ngenxa yokuba i-carbide stabilizer enamandla;i-nickel idla ngokudityaniswa kunye.Isixa esincinci setoti singongezwa njenge chromium eyi 0.5%.I-Copper yongezwa kwi-ladle okanye kwisithando somlilo, ngomyalelo we-0.5-2.5%, ukunciphisa i-chill, ukucoca i-graphite, kunye nokwandisa umbane.I-Molybdenum yongezwa ngomyalelo we-0.3-1% ukwandisa i-chill kunye nokucoca i-graphite kunye ne-pearlite structure;isoloko idityaniswa kunye ne-nickel, i-copper, kunye ne-chromium ukwenza ii-irons ezinamandla kakhulu.I-Titanium yongezwa njenge-degasser kunye ne-deoxidizer, kodwa iphinda inyuse umbane.I-0.15-0.5% ye-vanadium yongezwa kwintsimbi yokuphosa ukuzinzisa i-cementite, ukwandisa ubunzima, kunye nokwandisa ukuchasana nokugqoka kunye nokushisa.I-0.1-0.3% i-zirconium inceda ukwenza i-graphite, i-deoxidize, kunye nokwandisa umbane.

Kwi-iron enyibilikayo enyibilikayo, i-bismuth yongezwa, kwisikali se-0.002-0.01%, ukwandisa ukuba ingakanani i-silicon enokongezwa.Kwintsimbi emhlophe, i-boron yongezwa ekuncedeni ukuveliswa kwesinyithi esithambileyo;ikwanciphisa ifuthe elirhabaxa lebismuth.

Intsimbi engwevu

Intsimbi ye-Grey cast ibonakaliswe yi-graphitic microstructure, ebangela ukuphuka kwezinto ezibonakalayo zibe ngwevu.Yeyona nto isetyenziswa ngokuqhelekileyo intsimbi etyhidiweyo kunye neyona nto isetyenziswa ngokubanzi kwi-cast material esekelwe kubunzima.Uninzi lweentsimbi ezityhidiweyo zinemichiza ye-2.5-4.0% ye-carbon, 1-3% ye-silicon, kunye nentsimbi eseleyo.Intsimbi engwevu inamandla angaphantsi kokuqina kunye nokuxhathisa ukothuka kunentsimbi, kodwa amandla ayo okucinezela anokuthelekiswa nentsimbi ephantsi kunye nephakathi kwekhabhoni.Ezi zixhobo zoomatshini zilawulwa ngobukhulu kunye nokuma kweeflakes zegraphite ezikhoyo kwi-microstructure kwaye zingabonakaliswa ngokwemigaqo enikwe yi-ASTM.

Intsimbi emhlophe

Intsimbi yentsimbi emhlophe ibonisa imiphezulu eyaphukileyo emhlophe ngenxa yobukho bentsimbi ye-carbide precipitate ebizwa ngokuba yicementite.Ngomxholo osezantsi wesilicon (iarhente yegraphitizing) kunye nesantya sokupholisa ngokukhawuleza, ikhabhoni ekwintsimbi etyhidiweyo emhlophe iphuma ekunyibilikeni njenge metastable isigaba sesamente, Fe.₃C, kunegraphite.I-cementite enyukayo ukusuka kwiminyibiliko yenza njengamasuntswana amakhulu.Njengoko i-iron carbide iphumela ngaphandle, ikhupha ikhabhoni kwinyibilika yokuqala, ihambisa umxube kwindawo ekufutshane ne-eutectic, kwaye isigaba esiseleyo sisezantsi kwe-iron-carbon austenite (enokuthi xa ipholisa iguquke ibe yi-martensite).Ezi carbides ze-eutectic zinkulu kakhulu ukuba zingabonelela ngenzuzo yento ebizwa ngokuba yi-precipitation hardening (njengakwezinye iintsimbi, apho imvula yesamente encinci kakhulu inokuthintela [ukuguqulwa kweplastiki] ngokuthintela intshukumo yokukhutshwa nge-iron ferrite matrix ecocekileyo).Endaweni yoko, bonyusa ubulukhuni bentsimbi etyhidiweyo ngenxa yobulukhuni babo obuphezulu kakhulu kunye neqhezu labo levolumu enkulu, kangangokuba ubunzima besambuku bunokuqikelelwa ngomgaqo wokuxutywa.Kwimeko nayiphi na into, banikezela ngobunzima ngeendleko zobunzima.Ekubeni i-carbide yenza iqhezu elikhulu lezinto eziphathekayo, intsimbi emhlophe inokuthi ihlelwe ngokufanelekileyo njenge-cermet.Intsimbi emhlophe intekenteke kakhulu ukuba ingasetyenziswa kumalungu amaninzi olwakhiwo, kodwa ngokuqina okulungileyo kunye nokuxhathisa ukukrazuka kunye nexabiso eliphantsi ngokwentelekiso, ifumana ukusetyenziswa kwizinto ezinje ngokunxitywa komphezulu (i-impeller kunye nevolute) yeempompo eziludaka, iintambo zeqokobhe kunye nemivalo yokuphakamisa ebholeni. ii-mills kunye ne-autogenous grinding mill, iibhola kunye nemisesane kwi-pulverisers yamalahle, kunye namazinyo e-backhoe's emele yokumba (nangona intsimbi ephakathi kwekhabhoni ye-martensitic ixhaphake kakhulu kwesi sicelo).

Kunzima ukupholisa ii-castings ezishinyeneyo ngokukhawuleza ngokwaneleyo ukuqinisa ukunyibilika njengentsimbi etyhidiweyo emhlophe yonke indlela.Nangona kunjalo, ukupholisa ngokukhawuleza kunokusetyenziswa ukuqinisa iqokobhe lentsimbi emhlophe, emva koko intsalela iphole ngokucothayo ukwenza umbindi wentsimbi engwevu.Isiphumo sokuphosa, esibizwa ngokuba yi-aukuphosa okupholileyo, ineenzuzo zomphezulu oqinileyo kunye nendawo yangaphakathi eqinile.

I-high-chromium emhlophe ialloys yentsimbi ivumela ukutyhilwa okukhulu (umzekelo, i-impeller ye-10-tonne) ukuba yenze isanti, njengoko ichromium inciphisa izinga lokupholisa elifunekayo ukuvelisa i-carbides ngobunzima obukhulu bemathiriyeli.I-Chromium ikwavelisa ii-carbides ezinokuxhathisa okumangalisayo kwe-abrasion.Ezi ngxubevange eziphezulu zechromium zibalula ukuqina kwazo okuphezulu kubukho be-chromium carbides.Eyona ndlela iphambili yezi carbides yi-eutectic okanye i-primary M₇C₃i-carbides, apho i-"M" imele intsimbi okanye i-chromium kwaye inokwahluka ngokuxhomekeke kukwakheka kwe-alloy.I-eutectic carbides ibumba njengeenyanda zeentonga ezine-hexagonal ezingenanto kwaye zikhula ngokuthe ngqo kwi-hexagonal basal plane.Ukuqina kwezi carbides kuphakathi koluhlu lwe-1500-1800HV.

Intsimbi ethambileyo etyhidiweyo

Intsimbi ethambileyo iqala ngokugaywa kwentsimbi emhlophe ethi ke emva koko iphathwe ubushushu usuku okanye ezimbini malunga ne-950 °C (1,740 °F) emva koko ipholiswe isithuba sosuku okanye ezimbini.Ngenxa yoko, i-carbon kwi-iron carbide iguqula ibe yigraphite kunye ne-ferrite kunye ne-carbon (austenite).Inkqubo ecothayo ivumela ukuxinana komphezulu ukwenza igraphite ibe ngamasuntswana angama-spheroidal kunokuba iiflakes.Ngenxa yomlinganiselo wabo osezantsi, i-spheroids imfutshane kwaye ikude enye kwenye, kwaye inecandelo elisezantsi le-cross vis-a-vis a propagating crack or phonon.Bakwanayo nemida enqabileyo, ngokuchasene neeflakes, ezinciphisa iingxaki zokuxinzelela uxinzelelo ezifumaneka kwintsimbi engwevu.Ngokubanzi, iipropathi zentsimbi enyibilikayo zifana nezo zentsimbi ethambileyo.Kukho umda wokuba inxalenye enkulu inokuphoswa kwintsimbi ethambileyo, njengoko yenziwe ngentsimbi emhlophe.

Intsimbi yentsimbi