High-strength steels, such as high-strength bolts or steel plates are considerably sensitive to hydrogen embrittlement. Serious safety problems in steel structures are possible, because they are exposed to atmospheric condition containing chloride ions. Embrittlement is induced by hydrogen penetration during atmospheric corrosion. We developed Double-Head Scanning Kelvin Probe (DHSKP) equipment to clarify the relationship between the corrosion process and hydrogen permeation. Each probe can simultaneously measure the corrosion potential on the corroded side and surface potential on the hydrogen-detecting side at the same time. In this study, we investigated the correlation between the corrosion potential and hydrogen permeation under changing conditions from wet to dry processes on the surface of a steel sample. During the drying process, the corrosion potential at the rust layer that precipitated in the early wetting condition showed a less noble potential locally, whereas the surface potential of the Pd film on the hydrogen detection side showed a less noble potential locally. The hydrogen permeation sites were limited to small spots in the opposite area, where the corrosion potential showed a less noble local-potential during the drying process. Hydrogen penetration by corrosion likely occurs in acidic liquids under the rust layer during the drying process.

中文翻译：

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使用双头扫描开尔文探针同时测量腐蚀电位和氢渗透

高强度钢，例如高强度螺栓或钢板对氢脆非常敏感。钢结构可能会出现严重的安全问题，因为它们暴露在含有氯离子的大气条件下。大气腐蚀过程中氢渗透会引起脆化。我们开发了双头扫描开尔文探针（DHSKP）设备来阐明腐蚀过程与氢渗透之间的关系。每个探头可同时测量被腐蚀侧的腐蚀电位和检氢侧的表面电位。在这项研究中，我们研究了钢样品表面从湿法到干法过程变化条件下的腐蚀电位和氢渗透之间的相关性。在干燥过程中，早期润湿条件下析出的锈层的腐蚀电位局部表现出较低的贵族电位，而氢检测侧的Pd膜的表面电位则局部表现出较低的贵族电位。氢渗透位点仅限于相对区域的小点，在干燥过程中，腐蚀电位显示出不太高的局部电位。在干燥过程中，锈层下的酸性液体中可能会发生腐蚀引起的氢渗透。