镍基合金表面电化学表面改性

摘要

分别在硼酸缓冲溶液（pH=8．4）和0．1mol／LH28O4溶液中对镍基合金600和800进行电化学表面改性；对镍基合金表面氧化膜（改性前和改性后）进行动电位扫描、Mott-Schottky曲线测定以及利用光电流法绘制光电流谱。结果表明，镍基合金在酸性溶液中平带电位发生明显正移，载流子浓度升高，且在同样的电位范围呈现不同的半导体性质；电化学表面改性后，镍基合金生成的表面钝化膜平带电位没有发生明显变化，载流子浓度明显减小，表面钝化膜溶解的速度降低，耐蚀性能得到改善。%Electrochemical surface modification was carried out on nickel-base alloys 800 and 600 in borate buffer solution （pH=8. 4） and 0.1 mol/L H2 SO4 solution respectively. Passive films formed on nickel-based alloys 600 and 800 were investigated systematically by potentiodynamic scanning, Mott-Schottky curves and photo-current spectroscopy. The results showed that a positive shift in flat band potential and higher carried density was presented in H2SO4 solution. There was no significant change in flat band potential and significant decrease of carrier concentration for electrochemically modified specimens. Therefore, the rate of dissolution of passive films was reduced, and corrosion resistance was improved greatly.