Yawa yana ɗaya daga cikin abubuwa masu yawa na ƙarfe.Ana ƙididdige shi ta hanyar rarraba taro ta ƙarar.Karfe ya zo da nau'i daban-daban.Ana ƙididdige yawan ƙididdigewa ta hanyar rarraba taro ta ƙarar.Yawa na carbon karfe ne kamar 7.85 g/cm3 (0.284 lb/in3).

Akwai amfani da yawa ga karfe.Bakin karfe, alal misali, ana amfani da shi don kayan aikin tiyata da kayan dafa abinci.Wani nau'in karfe ne wanda ya ƙunshi ƙananan matakan carbon kuma aƙalla 10.5% na chromium.Wannan yana haifar da juriya na lalata.Wani irin karfe, kayan aikin karfe, ana amfani da kayan aikin yankan karfe don yin rawar jiki saboda yana da wuya, amma gatsewa.Yawan carbon a cikin carbon karfe yana ƙayyade taurin karfe.Yawan carbon ɗin da ya ƙunshi, ƙarfin ƙarfe ya fi ƙarfin.Ana yawan amfani da karfen carbon don sassan mota.

Karfe da nau'ikansa iri-iri suna da amfani da yawa a duniya.Yanayin karfe ya dogara da abun ciki, wanda ke haifar da nau'i daban-daban.A mafi yawan lokuta, mafi girman karfe, mafi wuyar shi ne.Yawancin adadin carbon, tsakanin sauran abubuwa a cikin kowane nau'in karfe suna haifar da iri-iri a cikin yawa ko takamaiman nauyi.(Takamaiman nauyi ko ƙaƙƙarfan dangi shine rabon girman abu da na ruwa.)

Akwai manyan rarrabuwa biyar na karafa: carbon karfe, gami karfe, babban ƙarfi low-alloy karfe, bakin karfe da kayan aiki karfe.Karfe-karfe sune suka fi kowa yawa, masu dauke da nau'in carbon iri-iri, suna samar da komai tun daga injina zuwa shimfidar gado zuwa filayen bobby.Alloy karafa suna da takamaiman adadin vanadium, molybdenum, manganese, silicon da cooper.Ƙarfe na alloy yana samar da kayan aiki, wuƙaƙen sassaƙa har ma da skate na nadi.Bakin karfe suna da chromium, nickel a tsakanin sauran abubuwan gami waɗanda ke ɗaukar launi da halayen tsatsa.Kayayyakin bakin karfe sun haɗa da bututu, capsules na sarari, kayan aikin tiyata zuwa kayan abinci.Ƙarshe amma ba kalla ba, kayan aiki na kayan aiki suna da tungsten, molybdenum a tsakanin sauran abubuwan gami.Wadannan abubuwa suna haifar da ƙarfi da ƙarfin kayan aikin ƙarfe na kayan aiki, wanda ya haɗa da sassa don ayyukan masana'antu da kayan aiki.