Water reduction, which leads to the evolution of hydrogen, is a key cathodic process for corrosion of many metals of technological interest such as magnesium, aluminium, and zinc; and its understanding is critical for design of new alloys or protective treatments. In this work, real-time hydrogen evolution measurement was coupled with potentiodynamic measurements on high-purity aluminium and AA2024-T3 aluminium alloy. The results show that both materials exhibit superfluous hydrogen evolution during anodic polarisation and that the presence of cathodically active alloying elements enhances hydrogen evolution. Furthermore, it was observed for the first time that superfluous hydrogen evolution also occurs during cathodic polarisation. Both the anodic and cathodic behaviours can be rationalised by a model assuming that superfluous hydrogen evolution occurs locally where the naturally formed oxide is disrupted. Specifically, during anodic polarisation, oxide disruption is due to the combined presence of chloride ions and acidification, whereas during cathodic polarisation, such disruption is due to alkalinisation. Furthermore, the presence of cathodically active alloying elements enhances superfluous hydrogen evolution in response to either anodic or cathodic polarisation, and results in ‘cathodic activation’ of the dissolved regions.

减水会导致氢的释放，是腐蚀许多具有技术意义的金属（例如镁，铝和锌）的关键阴极工艺。其理解对于设计新合金或进行防护处理至关重要。在这项工作中，实时氢析出测量与高纯度铝和AA2024-T3铝合金的电位动力学测量相结合。结果表明，两种材料在阳极极化过程中均显示出多余的氢逸出，并且阴极活性合金元素的存在会增强氢的逸出。此外，首次观察到在阴极极化过程中也发生了多余的氢逸出。可以通过一个模型来合理化阳极行为和阴极行为，该模型假设多余的氢放出发生在自然形成的氧化物被破坏的地方。具体地，在阳极极化期间，氧化物破坏是由于氯离子和酸化的结合存在，而在阴极极化期间，这种破坏是由于碱化。此外，阴极活性合金元素的存在增强了多余的氢对阳极或阴极极化的响应，并导致溶解区域的“阴极活化”。这种破坏是由于碱化。此外，阴极活性合金元素的存在增强了多余的氢对阳极或阴极极化的响应，并导致溶解区域的“阴极活化”。这种破坏是由于碱化。此外，阴极活性合金元素的存在增强了多余的氢对阳极或阴极极化的响应，并导致溶解区域的“阴极活化”。