A、共析鋼的C%=0.77% B、亞共析鋼的碳含量為0.0218≤C%<0.77% C、過共析鋼的碳含量0.77%<C<2.11% D、工業(yè)純鐵的碳含量為C%≤0.0218%
A.大于 B.小于 C.等于