为了研究磁场对AZ31B镁合金在2种不同浓度的NaCl溶液中腐蚀行为的影响,采用COMSOL分析磁场在电化学反应体系中的磁场强度分布,考察了磁场环境对AZ31B镁合金在0.1 mol/L和1.0 mol/L NaCl溶液中动电位极化和电化学阻抗的影响。结果表明:通过仿真加入400 mT平行磁场后,镁合金表面磁场强度分布不均匀。在0.1 mol/L NaCl溶液中施加400 mT平行磁场后,AZ31B镁合金自腐蚀电位升高,腐蚀电流降低,点蚀数量减小,镁合金在低浓度NaCl溶液中的腐蚀速率被抑制。在1.0 mol/L NaCl溶液中施加400 mT磁场后,AZ31B镁合金自腐蚀电位负移,腐蚀电流升高,点蚀数量增加,连接在一起并出现钝化膜破裂,镁合金在高浓度NaCl溶液中的腐蚀速率得到提高。
For studying the effect of magnetic field on the corrosion behavior of AZ31B magnesium alloy in NaCl solutions with two different concentrations, the magnetic field intensity distribution of the magnetic field in the electrochemical reaction system was analyzed by COMSOL, and the dynamic potential polarization and electrochemical impedance of AZ31B magnesium alloy in 0.1 mol/L and 1.0 mol/L NaCl solution were studied under magnetic field.Results showed that after adding 400 mT magnetic field by simulation, the magnetic field intensity distribution on the magnesium alloy surface became uneven.In 0.1 mol/L NaCl solution, the self-corrosion potential of AZ31B magnesium alloy increased, the corrosion current decreased and the pitting amount decreased, signaling that the corrosion rate of magnesium alloy decreased after adding 400 mT magnetic field.In 1.0 mol/L NaCl solution, after adding 400 mT magnetic field, the self-corrosion potential of AZ31B magnesium alloy shifted negatively, the corrosion current increased, the number of pitting corrosions increased then the pitting connected with each other and the passivation film broke, which indicated the corrosion rate of AZ31B magnesium alloy in high concentration NaCl solution increased.