外加应力下的LY12CZ电化学行为

利用动电位极化和电化学阻抗谱技术对应力加载下的LY12CZ铝合金在3％NaCl水溶液中的腐蚀行为进行了研究,考察了应力作用对LY12CZ在3％NaCl水溶液中的阳极极化行为、自腐蚀电位和破裂电位以及极化电阻和双电层电容大小的影响.结果表明,在加载应力时LY12CZ的阳极极化曲线和自腐蚀电位、破裂电位均明显负移;在浸泡时间相同的情况下,极化电阻也随应力的增加而显著降低,在应变强化阶段力学化学效应达到最大.破裂电位的负移和极化电阻的降低说明应力对LY12CZ的局部腐蚀有明显的影响.

Electrochemical behaviour of LY12CZ under applied stress

Potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) techniques were applied to investigate the corrosion behavior of LY12CZ in 3%NaCl aqueous solution.The effects of stress to anodic polarization behavior,free corrosion potential,breakdown potential,polarization resistance and double-layer capacitance of LY12CZ were summarized.Results show that the polarization curve and breakdown potentials show obvious negative removals,and the mechanochemical effects reached maximum during the strain hardening stage.If stressed,under equivalent immersion time,polarization resistance also decreased significantly with the increase of stress.The nagetive removal of breakdown potential and decrease of polarization resistance indicate that stress plays an important role in the localized corrosion of LY12CZ.