Abstract
The interaction between silicon and carbon atoms is discussed in Fe-C Si-steels which have been quenched from 823-973K to 273K and then aged at 523K.The changes in electrical resistivity and its deviation from Matthiessen's rule (DMR) during aging were examined for 0.04mass% carbon steels containing from 0.01 to 0.56 mass% silicon. The DMR was obtained from the difference between the electrical resistivity measured at 77K and 273K. The electrical resistivity during aging decreases for all steels which have been quenched from the ferrite phase region. The DMR increases for steels except the 0.01mass% silicon steel. The more the silicon content, the more the increments in DMR. These results can be explained from the assumption that the Si-C pairs formed in the as-quenched ferrite matrix would be decomposed with the precipitation of carbide during aging, corresponding to Mn-C(N) dipoles in Fe-Mn-C(N)alloys. The amount of solute carbon atoms, which was occurred by the decomposition of Si-C pairs and then contributed to the precipitation of carbide, increases with the increase of silicon content. The Si-C pairs may be formed in a short time during quenching by elastic interaction between silicon and carbon atoms, whereas the Mn-C(N)dipoles were combined at high temperature during solid solution treatment by chemical interaction between manganese and carbon atoms.
