Farin simintin ƙarfe: Kamar dai sukarin da muke sawa a cikin shayi, carbon ɗin yana narkewa gaba ɗaya cikin ƙarfe na ruwa. Idan wannan carbon da ke narkar da ruwa ba za a iya raba shi da baƙin ƙarfe na ruwa ba yayin da simintin ƙarfe ya ƙarfafa, amma ya kasance gaba ɗaya narkar da shi a cikin tsarin, muna kiran tsarin da ya haifar da farin ƙarfe. Farin simintin ƙarfe, wanda ke da tsari mara ƙarfi, ana kiransa farin simintin ƙarfe saboda yana nuna launin fari mai haske idan ya karye.
Simintin ƙarfe mai launin toka: Yayin da ruwan simintin ƙarfe ya daɗa ƙarfi, carbon ɗin da ke narkewa a cikin ƙarfen ruwa, kamar sukari a cikin shayi, na iya fitowa a matsayin wani lokaci na daban yayin ƙarfafawa. Lokacin da muka bincika irin wannan tsari a ƙarƙashin na'urar hangen nesa, zamu ga cewa carbon ya bazu zuwa wani tsari daban wanda ake iya gani ga ido tsirara, a cikin nau'i na graphite. Muna kiran irin wannan nau'in simintin ƙarfe a matsayin ƙarfe mai launin toka, domin lokacin da wannan tsari, wanda carbon ɗin ya bayyana a cikin lamellae, wato, a cikin yadudduka, ya karye, launi mai laushi da launin toka yana fitowa.
Simintin simintin gyare-gyare: Farar simintin ƙarfe da muka ambata a sama suna fitowa a cikin yanayin sanyi mai sauri, yayin da simintin launin toka ya bayyana a cikin yanayin sanyi a hankali. Idan adadin sanyaya na ɓangaren da aka zubar ya zo daidai da kewayon inda canji daga fari zuwa launin toka ke faruwa, yana yiwuwa a ga cewa sifofin launin toka da fari sun bayyana tare. Muna kiran waɗannan ƙarfen simintin gyare-gyare don lokacin da muka karya irin wannan guntu, tsibiran launin toka suna bayyana a bangon fari.
Simintin simintin gyare-gyare: Wannan nau'in simintin ƙarfe yana da ƙarfi a zahiri kamar farin simintin ƙarfe. A wasu kalmomi, ana tabbatar da ƙarfafa ƙarfen simintin gyare-gyare ta yadda carbon ɗin ya kasance gaba ɗaya narkar da shi a cikin tsarin. Sa'an nan kuma, ƙaƙƙarfan farin simintin ƙarfe yana ƙarƙashin magani mai zafi ta yadda carbon ɗin da ke narkar da shi ya rabu da tsarin. Bayan wannan magani na zafi, muna ganin cewa carbon yana fitowa a matsayin nau'i mai siffar da ba daidai ba, tari.
Baya ga wannan rarrabuwa, idan carbon ya sami damar rabuwa daga tsarin sakamakon ƙarfafawa (kamar yadda yake a cikin simintin simintin launin toka), za mu iya yin wani rarrabuwa ta hanyar kallon kaddarorin da aka samu na graphite:
Grey (Lamellar graphite) simintin ƙarfe: Idan carbon ya ƙarfafa yana haifar da tsarin zane mai launi kamar ganyen kabeji, muna nufin irin waɗannan ƙarfe na simintin ƙarfe kamar launin toka ko lamellar graphite cast irons. Za mu iya ƙarfafa wannan tsari, wanda ke faruwa a cikin allunan da iskar oxygen da sulfur ke da girma, ba tare da nuna yawan raguwa ba saboda yawan ƙarfin zafi.
Spherical graphite jefa baƙin ƙarfe: Kamar yadda sunan ke nunawa, mun ga cewa a cikin wannan tsari, carbon yana bayyana a matsayin ƙwallayen graphite. Domin graphite ya bazu cikin tsari mai siffar zobe maimakon tsarin lamellar, dole ne a rage iskar oxygen da sulfur a cikin ruwa a ƙasa da wani matakin. Shi ya sa a lokacin samar da spheroidal graphite jefa baƙin ƙarfe, mu bi da ruwa karfe da magnesium, wanda zai iya yi da sauri da oxygen da sulfur, sa'an nan kuma zuba shi a cikin molds.
Simintin simintin gyare-gyaren graphite: Idan maganin magnesium da aka yi amfani da shi yayin samar da simintin simintin gyare-gyaren graphite bai wadatar ba kuma ba za a iya spheroid ɗin graphite gaba ɗaya ba, wannan tsarin graphite, wanda muke kira vermicular (ko ƙarami), na iya fitowa. Vermicular graphite, wanda shine nau'i na tsaka-tsakin tsaka-tsaki tsakanin nau'in lamellar da nau'in spheroidal graphite, ba wai kawai yana samar da baƙin ƙarfe tare da manyan kayan aikin injiniya na graphite ba, amma kuma yana rage haɓakar haɓakar haɓakar haɓakar zafi. Wannan tsarin, wanda ake la'akari da kuskure wajen samar da simintin simintin gyare-gyare na spheroidal graphite cast iron, da gangan aka jefa shi ta hanyar gano abubuwa da yawa saboda fa'idodin da aka ambata a sama.
Lokacin aikawa: Maris 29-2023