表面粗糙度对X70碳钢在HNO3溶液中阳极溶解行为的影响∗

摘要

采用动电位极化和恒电位极化技术研究了表面粗糙度对X70碳钢在0．5 mol/L HNO3溶液中的阳极溶解行为产生的影响。 X70碳钢在0．5 mol/L HNO3溶液中发生阳极溶解时有电流振荡现象出现，振荡是由电极表面膜的周期性生成和溶解导致的。通过分析不同表面粗糙度时的电流振荡，得出结论：表面比较粗糙时，电极难以钝化，阳极溶解比较剧烈；相反，表面非常光滑时，电极容易钝化，阳极溶解比较轻微。%Effects of surface roughness on the anodic dissolution of X70 carbon steel in 0. 5 mol/L HNO3 solution were studied by potentiodynamic and potentiostatic polarization techniques. By analyzing the current oscillations of the electrodes with different surface roughness, some conclusions can be drawn. With the increase of the surface roughness, the electrode was hard to be passivated, thus the anodic dissolution increased. On the contrary, if the electrode surface was very smooth, it was easy to passive the electrode, and the anodic dissolution decreased.