It can be identified that tin distributes
uniformly in the steel and there is no obvious segregation under the
condition of 0.038 wt.% addition. Gibbs function: ΔG = − nFΔE (n:
Electron transfer number, F: Faraday's constant) can judge the direction
of reaction. Electrochemical reaction could proceed when ΔG b 0, and
corrosion tendency will be enlarged when the value ofΔE increases
(ΔE = Eec − Eea,Eec: cathode potential, Eea: anode potential.