Revealing the localized corrosion process of Mg alloy is considered as one of the most significant ways for improving its corrosion resistance. The reliable monitor should be high distinguishability and real-time in liquid environment. Herein, Mg-9Al-1Fe and Mg-9Al-1Fe-1Gd alloys were designed to highlight the impact of intermetallic on the corrosion behaviour. In-situ AFM with a special electrolyte circulation system and quasi-in-situ SEM observation were used to monitor the corrosion process of the designed alloys. SEM-EDS and TEM-SAED were applied to identify the intermetallic in the designed alloys, and their volta potentials were measured by SKPFM. According to the real-time and real-space in-situ AFM monitor, the corrosion process consisted of dissolution of anodic α-Mg phase, accumulation of corrosion products around cathodic phase and shedding of some fine cathodic phase. Then, the localized corrosion process of Mg alloy was revealed combined with the results of the monitor of corrosion process and Volta potential difference.

中文翻译：

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3.5 wt.% NaCl 环境下 Mg-9Al-1Fe-(Gd) 合金局部腐蚀的原位 AFM 和准原位研究

揭示镁合金的局部腐蚀过程被认为是提高其耐腐蚀性能的最重要途径之一。可靠的监测在液体环境下应具有高分辨力和实时性。本文设计了 Mg-9Al-1Fe 和 Mg-9Al-1Fe-1Gd 合金，以强调金属间化合物对腐蚀行为的影响。采用具有特殊电解液循环系统的原位原子力显微镜和准原位扫描电镜观察来监测所设计合金的腐蚀过程。应用SEM-EDS和TEM-SAED来识别设计合金中的金属间化合物，并通过SKPFM测量它们的伏特电势。根据实时、实空间原位AFM监测，腐蚀过程包括阳极α-Mg相的溶解、阴极相周围腐蚀产物的积累以及一些细小的阴极相的脱落。然后结合腐蚀过程和Volta电位差的监测结果揭示了镁合金的局部腐蚀过程。