Corrosion Properties of Rapidly Solidified CuSn Alloys

Two rapidly solidified CuSn alloys were prepared by copper mold casting. The phase composition and electronic resistivity of the two alloys were analyzed by XRD and four-probe method. And the corrosion behaviors of the alloys in NaOH solution were also studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results show that the phase of the rapidly solidified Cu75Sn25 alloy was Cu3Sn while the rapidly solidified Cu65Sn35 consisted of Cu6Sn5 and Cu3Sn. Due to the formation of intermetallic compounds, the electronic resistances were nearly the same for the two alloys. The rapidly solidified alloy Cu65Sn35 had more excellent corrosion resistance than rapidly solidified alloy Cu75Sn25 in 0.1 mol/L NaOH solution.