在模拟浪花飞溅区环境中采用外加电流法对Q235A钢实施阴极保护, 通过保护电流密度、电化学性能试验, 腐蚀形貌观察和保护效率计算研究了保护电位对Q235A钢保护效果的影响。结果表明: 在恒电位控制下, 保护电流密度在初期较大, 之后急速下降并逐级稳定在100 mA/m2以下; 不同保护电位下, 由于表面形成钙镁沉积物, 试验钢的极化电阻急剧增大; 随着保护电位的负移, 阻抗弧直径变大, 膜的保护性能加强; 恒电位控制在-850 mV(vs.SCE)及析氢电位之间时, 保护效率可以达到98%以上。

The method of impressed current was used to protect Q235A steel in simulated splash zone. The experiments of protective current density, electrochemical properties, morphology observation and calculation of protective efficiency were carried out to study the effect of protective potential on the protective results. The results indicate that under the control of constant potential, the values of initial current density were very large, then decreased rapidly and gradually stabilized below 100 mA/m2. At different protective potentials, the polarization resistance of the test steel increased rapidly because of the formation of calcium/magnesium deposits on the surface. As the protection potential became negative, the diameters of the impedance arc became larger and the protective property of the film was be strengthened. If the potentials were between -850 mV (vs. SCE) and the over potential of hydrogen evolution, the protective efficiency could reach more than 98%.