Железни материали
Черните метали се наричат още стоманени материали, включително чисто желязо от промишлеността с общо<0.2% and="" a="" carbon="" content="" of="" not="" more="" than="" 0.0218%,="" steel="" with="" a="" carbon="" content="" of="" 0.0218%="" to="" 2.11%,="" and="" cast="" iron="" with="" a="" carbon="" content="" of="" more="" than="" 2.11%.="" the="" broad="" ferrous="" metals="" also="" include="" chromium,="" manganese="" and="" their="">