Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《中国腐蚀与防护学报》
Abstract: The debonding process of organic coatings with desired artificial defects in 3.5%NaCl solution was studied by means of wire beam electrode (WBE) method and electrochemical impedance spectroscopy (EIS) technique. The purpose was to reveal the relevant debonding mechanism of organic coatings in the area nearby water-line via analyzing the current distribution and the variation of impedance spectroscopy during the experiment. It was found that, either the artificial defect or inherent defect could accelerate cathodic debonding rate of the coating around the defects. Besides, due to the effect of waterline, a coating debonding, which initiated from one inherent defect will expand towards the waterline. The coating debonding occurred firstly on the area below the waterline, and then later above the waterline. The coating debonding rate on the area above waterline was controlled by the permeation rate of electrolyte through the coating.
Subjects: Geosciences >> Marine Sciences Subjects: Materials Science >> Materials Science (General) submitted time 2017-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract:通过海水飞溅区暴露试验,获得了2种含镍钢和碳钢3a的腐蚀结果。采用X-射线衍射(XRD)和电子探针显微分析(EPMA)技术,研究了含镍钢飞溅区锈层的特性,讨论了Ni对钢飞溅区锈层及耐蚀性的影响。结果表明,添加2%~3%Ni,使钢锈层中的裂纹和孔洞减小, 锈层的致密度提高;外锈层中的?-FeOOH的含量增加。2%~3%Ni的加入有利于盐分中的Na+和Mg++向锈层和钢基体界面渗透,对Cl?的渗透有抑制作用。添加3%Ni,使钢的蚀孔中的Cl?富集程度显著降低。加入2%~3%Ni能大幅度提高钢在飞溅区的耐蚀性。