It can be seen from Fig. 3 that Fermi energy of tin-containing
atomic is lower than that of Fe–C atomic. The value reduced by tin is
higher than that reduced by Cr or Cu, which proves a tendency that
the tin addition can reduce Fermi energy of steel in some extent.
Fig. 2(b) shows that the distribution of tin is uniform, which indicates
that tin can increase tin-containing steel's oxidation resistance evenly.
This effect is conducive to improve the corrosion resistance of the tin containing
steel.