Ziziphi iimpembelelo ze-silicon ephezulu okanye ephantsi ekusebenzeni komatshini we-grey cast iron 200?

Impembelelo ye-silicon ekusebenzeni kwentsimbi engwevu ayiyona nje "ingcono" okanye "imbi", kodwa kukho uluhlu olufanelekileyo.

Impembelelo yayo ibonakala ikakhulu kule miba ilandelayo:

1. Impembelelo entle: ikhuthaza igraphitization kwaye iphucula ukuqhubekeka. Umsebenzi ongundoqo: I-silicon yinto eyomeleleyo ye-graphitizing. Inokukhuthaza imvula yekhabhoni ngendlela yegraphite (kunokuba i-Fe-C eqinile kunye ne-brittle cementite). Ubuchwephesha: Igraphite ngokwayo sisithambiso esilungileyo esiqinileyo. Ngethuba lenkqubo yokusika, i-graphite eveziweyo kwindawo yokuqhawula i-chip inokubonelela nge-lubrication phakathi kwendawo yokusika yangaphambili kunye ne-chip, kunye naphakathi kwendawo yokusika ngasemva kunye nomatshini owenziweyo, ukunciphisa ukungqubuzana, amandla okusika, kunye nokuqokelela ukushisa. Isiphumo: Oku kwenza iitshiphusi zithande ukophuka kwaye zikhusela isixhobo, ngaloo ndlela ziphucula ubomi besixhobo kunye nokuguda komphezulu. Intsimbi engwevu ephoswe ngepearlite njenge-matrix kunye ne-graphite yohlobo olufanayo lwe-A inokusebenza kakuhle.

2. Imiphumo emibi (eyaneleyo okanye egqithisileyo): Umxholo we-silicon ephantsi (<1.0%): Ingxaki: Ukungaphumeleli kwe-graphitization ukukwazi ukukhokelela ekubunjweni kwe-carbides yamahhala kwi-castings, ngokukodwa kwiindawo ezinqabileyo ezinqabileyo okanye ezipholile ngokukhawuleza. Impembelelo ekusebenzeni: I-cementite inzima kakhulu (> 800HB) kwaye sisigaba esibi kakhulu sokuqhaqha. Ubukho bayo buya kwandisa ngokukhawuleza ukunxiba kwesixhobo, okukhokelela kubunzima bomatshini kunye neendawo ezirhabaxa. Le yenye yeemeko ezimbi kakhulu. Umxholo we-silicon ophezulu (>2.8% -3.0%, kuxhomekeke kwimeko ethile):

Ingxaki 1: I-Ferritization: Isisombululo esiqinileyo seSilicon kwi-ferrite siya kusomeleza kwaye siqine. I-silicon egqithisileyo iya kuzinza kwaye inyuse inani lesigaba se-ferrite, okukhokelela ekunciphiseni kobunzima obupheleleyo kodwa ukwanda kokuqina kwe-matrix. Impembelelo ekuqhubekekeni: Le yingxaki kanye odibene nayo ngaphambili. I-matrix ethambileyo neyomeleleyo ye-ferrite iya kuvelisa "isixhobo sokuncamathela" into ngexesha lokusika, ukwenza iidiphozithi ze-chip, ezikhokelela ekunxityweni kwesixhobo esiqatha, ukukrazuka komphezulu kunye neetshiphusi ezinde. Ukuqhubekeka kuyawohloka.

Umbuzo 2: Ukuqina ngokubanzi kwe-matrix: I-silicon ngokwayo inokunyusa amandla kunye nobunzima be-ferrite. Xa umxholo we-silicon uphezulu kakhulu, nangaphandle kwe-cementite, yonke i-pearlite + i-ferrite matrix iya kuba nzima ngenxa yesisombululo esiqinileyo sokuqinisa i-silicon, ukwandisa ukuxhathisa ukusika.

Ingxaki yesi-3: Ukuwohloka kwe-graphite morphology: Ukugqithisa kwe-silicon kunokubangela ukuba i-graphite flakes ibe yi-coarse okanye ingalingani, yenza buthathaka i-matrix, kwaye ichaphazele i-chip breaking effect. Isishwankathelo se-curve ye-silicon ekuqhubekeni: Ukucutshungulwa kufikelela kweyona nto iphezulu kumxholo we-silicon ophakathi. Zombini eziphantsi kakhulu (ukuvelisa i-cementite) kwaye ziphezulu kakhulu (ezibangela ukubunjwa kwe-ferrite okanye amandla amaninzi e-matrix) kunokonakaliswa kobuchule. Uluhlu olufanelekileyo lokulawula i-silicon kwi-HT200 lelona nqanaba lisezantsi le-grey cast iron, ene-"200" emele amandla okuqina angekho ngaphantsi kwe-200 MPa.

Uyilo lokuqulunqa kufuneka lugxininise ekuhlangabezaneni nala mandla njengeyona njongo iphambili, ngelixa kuqwalaselwe zombini ukuphosa kunye nokusebenza.

Kwi-HT200, uluhlu oluqhelekileyo lolawulo lwe-silicon luhlala luphakathi kwe-1.8% kunye ne-2.4%. Olu luhlu lweklasikhi olulinganisa amandla, ukuphosa, kunye nobuqili.

2. Kufuneka kuthathelwe ingqalelo ngokubambisana nomxholo wekhabhoni: Ingcamango ye-carbon equivalent (CE) ayinantsingiselo ukuxoxa nge-silicon yodwa kwaye kufuneka ijongwe ngokubambisana nekhabhoni (C). Sisebenzisa ukulingana kwekhabhoni ukuvavanya ngokubanzi ukuthambekela kwegraphitization yentsimbi etyhidiweyo: CE=C%+(Si%+P%)/3. Kwi-HT200, i-carbon elingana ne-CE idla ngokulawulwa phakathi kwe-3.9% kunye ne-4.2%. Injongo: Ukufumana i-100% ye-pearlite matrix+esasazwe ngokulinganayo uhlobo lwegraphite ye-A ngaphandle kweekhabhidi zasimahla.

3. Isicwangciso soyilo lokuqulunqa: Ukuze kuqinisekiswe amandla kunye nokuqhubekeka kakuhle, uyilo lokwakheka kweHT200 ludla ngokulandela umgaqo othi "ukulingana kwekhabhoni ephezulu +i-alloying ephantsi" okanye "i-carbon equivalent ephakathi+i-incubation treatment". Inketho A (engcono kakhulu kwi-machinability): Yamkela i-CE ngokusondeleyo kumda ophezulu (ofana ne-4.1-4.2%), oku kuthetha ukuba i-C ephezulu kunye ne-Si, ukuqinisekisa ukungabikho okupheleleyo kwe-carbides kunye nesiseko esihle sokusebenza. Kodwa ukuze uhlawule ukuncipha kwamandla okubangelwa yi-CE ephezulu, kunokufuneka ukongeza inani elincinci lezinto ezizinzisayo ze-pearlite, ezifana ne-Sn (tin, 0.05-0.1%) okanye i-Cu (ubhedu, i-0.3-0.6%). Ezi zinto zinokucokisa kwaye zizinzise i-pearlite, ziqinisekisa ukuba amandla ahlangabezana nemigangatho ngelixa angabeki esichengeni ukusebenza. UKhetho B (lunoqoqosho ngakumbi): Yamkela i-CE ephakathi (efana ne-3.9-4.0%), idityaniswe nonyango olusebenzayo lokufukamela. Ukunyangwa kokuchuma kunokukhuthaza ngokufanelekileyo i-graphite nucleation, nokuba umxholo we-C kunye no-Si awuphezulu, unokuphepha ukuphosa okumhlophe kwaye ufumane i-graphite encinci ye-A, ngaloo ndlela iqinisekisa amandla kunye nokuqhubekeka.

Indlela yokumisela i-silicon ethile kwi-carbon ratio ye-HT200 ngaphakathi koluhlu lolawulo lwe-silicon ukuya kwi-carbon ratio? I-silicon kwi-carbon ratio kufuneka ithathelwe ingqalelo ngokubambisana ne-carbon equivalent (CE) kunye nokuphosa udonga lobunzima. ICarbon Equivalent CE=C%+(Si%+P%)/3 UmGaqo: Ngelixa uqinisekisa ukuba iimfuno zamandla eHT200 ziyafezekiswa, zama ukusebenzisa izixa eziphezulu zekhabhoni ukuze ufezekise ukuphosa nokusetyenzwa ngcono.

Amanyathelo athile acetyisiweyo:

Ukumisela i-target target equivalent (CE): Kwi-HT200, i-CE idla ngokulawulwa kwi-3.9% -4.1%, efanelekileyo. 2. Ngokwesicwangciso sokukhetha ubuninzi bodonga: Kwiindawo eziqhelekileyo ezinobunzima obuphakathi (15-30mm), i-CE ephezulu (efana ne-4.05%) kunye ne-silicon ephezulu ukuya kwi-carbon ratio (efana ne-0.65-0.70) ingasetyenziswa. Oku kuqinisekisa ulungelelwaniso oluhle kunye nokuqhubekeka okugqwesileyo. Ukuphoswa okukhulu kunye nokukhulu: Ukuthintela amandla anganeleyo abangelwa yi-graphite enqabileyo, i-CE (efana ne-3.95%) kunye ne-silicon carbon ratio (efana ne-0.60-0.65) inokunciphisa ngokufanelekileyo, kunye nenani elincinci lezinto zokuzinzisa i-pearlite (ezifana ne-Cu, Sn) zingasetyenziswa ngokudibeneyo. Ukuphosa okuncinci: Ukuthintela ukuphosa okumhlophe, i-CE kunye ne-silicon carbon ratio inokunyuswa ngokufanelekileyo (njenge-0.70-0.75) ukuphucula isakhono se-graphitization.

Umzekelo woyilo lwesithako uthatha i-CE ekujoliswe kuyo ye-4.0% kunye ne-silicon kwi-carbon ratio target ye-0.65. Sinokubala ukuba i-C = 3.30%, ngoko Si = 3.30% × 0.65 ≈ 2.15%. Ukuqinisekiswa kwe-CE = 3.30 + (2.15) / 3 ≈ 3.30 + 0.72 = 4.02% (ihlangabezana neemfuno). Le yifomyula yesithako esiqhelekileyo kwaye izinzile yeHT200. Ngesi siseko, ukulungelelaniswa kunokuphunyezwa ngokulungiswa kakuhle (njengokunyusa i-C ukuya kwi-3.35%, i-Si ukuya kwi-2.20%, i-Si / C ≈ 0.66).