Hu Pengfei, Cai Guangyi, Li Yizhou
National Key Laboratory of Science and Technology on Electromagnetic Energy, Naval University of Engineering, Wuhan 430033, China.
East Lake Laboratory, Wuhan 420202, China.
Materials (Basel). 2024 Aug 16;17(16):4078. doi: 10.3390/ma17164078.
The effect of crevice size on the crevice corrosion of N80 carbon steel was investigated by electrochemical measurements and surface analysis in a CO-saturated NaCl-HAc solution. The N80 carbon steel exhibits a high susceptibility to crevice corrosion in this environment, which can be initiated immediately without an induction period for specimens with crevice sizes of 100 μm, 300 μm, and 500 μm. Typically, crevice solutions become more acidic during crevice corrosion; however, in this study, the crevice solution became alkaline, resulting in galvanic corrosion between the inner and outer steel surfaces and leading to severe crevice corrosion. The pH levels of the crevice solution for specimens with 100 μm and 300 μm crevice sizes are similar, but both are notably higher than that of the specimen with a 500 μm crevice size. As a result, there is no significant difference in the crevice corrosion phenomenon between specimens with 100 μm and 300 μm crevice sizes, but it is more severe than in the specimen with a 500 μm crevice size.
通过在CO饱和的NaCl-HAc溶液中进行电化学测量和表面分析，研究了缝隙尺寸对N80碳钢缝隙腐蚀的影响。在这种环境下，N80碳钢对缝隙腐蚀表现出高度敏感性，对于缝隙尺寸为100μm、300μm和500μm的试样，缝隙腐蚀可立即开始，无诱导期。通常，缝隙腐蚀过程中缝隙溶液会变得更酸；然而，在本研究中，缝隙溶液变为碱性，导致钢内外表面之间发生电偶腐蚀，从而引发严重的缝隙腐蚀。缝隙尺寸为100μm和300μm的试样的缝隙溶液pH值相似，但均明显高于缝隙尺寸为500μm的试样。因此，缝隙尺寸为100μm和300μm的试样之间的缝隙腐蚀现象没有显著差异，但比缝隙尺寸为500μm的试样更严重。
