Carbone (C): Ibirimo bya karubone mu byuma byiyongera, aho bitanga umusaruro, imbaraga zingana no gukomera biriyongera, ariko plastike nibintu bigira ingaruka bigabanuka. Iyo karubone irenze 0.23%, imikorere yo gusudira ibyuma irangirika, niba rero ikoreshwa mugusudira Ibirimo bya karubone yibikoresho byubatswe buke buke muri rusange ntibirenza 0,20%. Ibirimo byinshi bya karubone bizagabanya kandi kwangirika kwikirere kwangirika kwicyuma, kandi ibyuma bya karuboni nyinshi mukibuga cyafunguye biroroshye kubora; byongeyeho, karubone irashobora kongera ubukonje bukabije hamwe no gusaza kwicyuma.
Silicon (Si): Silicon yongeweho nkibintu bigabanya na deoxidizer mugikorwa cyo gukora ibyuma, bityo ibyuma byishe birimo silikoni 0.15-0.30%. Silicon irashobora kuzamura cyane imipaka ya elastike, umusaruro utanga nimbaraga zicyuma cyicyuma, bityo ikoreshwa cyane nkibyuma byoroshye. Kwiyongera kwinshi kwa silicon bizagabanya imikorere yo gusudira ibyuma.
Manganese (Mn). Mubikorwa byo gukora ibyuma, manganese ni deoxidizer nziza na desulfurizer. Mubisanzwe, ibyuma birimo 0.30-0.50% manganese. Manganese irashobora kongera imbaraga nubukomezi bwibyuma, kongera ubukana bwibyuma, kunoza imikorere ishyushye yicyuma, no kugabanya imikorere yo gusudira ibyuma.
Fosifore (P): Mubisanzwe, fosifore nikintu cyangiza mubyuma, byongera ubukonje bukabije bwibyuma, byangiza imikorere yo gusudira, bigabanya plastike, kandi bikangiza imikorere yubukonje bukonje. Kubwibyo, ibirimo fosifore mubyuma mubisanzwe birasabwa kuba munsi ya 0.045%, kandi ibyangombwa byicyuma cyiza biri hasi.
Amazi (S): Amazi meza nayo ni ikintu cyangiza mubihe bisanzwe. Kora ibyuma bishyushye, gabanya guhindagurika kwicyuma no gukomera, kandi utere ibice mugihe cyo guhimba no kuzunguruka. Amazi ya sufuru nayo yangiza imikorere yo gusudira, kugabanya kurwanya ruswa. Kubwibyo, ibirimo sulfure muri rusange birasabwa kuba munsi ya 0.045%, kandi ibyangombwa byibyuma byo murwego rwo hejuru biri hasi. Ongeraho 0.08-0.20% sulfure mubyuma birashobora kunoza imashini, kandi mubisanzwe byitwa ibyuma bikata kubusa.
Vanadium (V): Ongeramo vanadium mubyuma birashobora gutunganya ingano yimiterere no kunoza imbaraga nubukomere.
Niobium (Nb): Niobium irashobora gutunganya ibinyampeke no kunoza imikorere yo gusudira.
Umuringa (Cu): Umuringa urashobora kunoza imbaraga no gukomera. Ikibi ni uko ikunda guhura n'ubushyuhe mugihe cyo gukora gishyushye, kandi ibirimo umuringa mubyuma bishaje akenshi usanga biri hejuru.
Aluminium (Al): Aluminium ni deoxidizer ikoreshwa cyane mubyuma. Umubare muto wa aluminiyumu wongeyeho ibyuma kugirango utunganyirize ingano kandi unoze ingaruka zikomeye.