AA5083铝合金在海水中的腐蚀行为研究

Research on Corrosion Behavior of AA5083 Aluminum Alloys in Seawater

采用电化学工作站研究了AA5083铝合金在海水中的极化曲线、点蚀电位、交流阻抗等性能,通过高分辨率数码显微镜、扫描电镜等表征手段对AA5083铝合金腐蚀前后的表面形貌进行了研究。研究结果表明:AA5083铝合金在静态海水中的腐蚀以点腐蚀为主,浸泡初期阻抗由容抗和感抗组成,腐蚀电位随着浸泡时间的延长不断负移,耐腐蚀性降低,点腐蚀坑越来越多,并且点腐蚀坑不断增大加深,在试板表面中间区域形成半球状点腐蚀坑,腐蚀达到一定程度后,出现Warburg阻抗,腐蚀电位逐渐稳定在-0.58V。

The multiple measurements of AA5083 in seawater including polarization curves, dot corrosion potentials, AC impedance were studied by using electrochemical workstation, and the surface corrosion configuration of AA5083 in seawater was also studied by highly distinguished digital microscope and SEM. AA5083 in static seawater was mainly point corrosion, and in the initial stage the impedance was comprised of capability and resistance. With extend of immersion time, corrosion potentials of AA5083 shifted to the negative region, and the anti-corrosion of AA5083 reduced and point corrosion increased and deepened, and in the middle region of the sample surface the hemi- spherical corrosion dot occurred. While corrosion continued to happen on the AA5083 surface, Warburg impedance would take place, and corrosion potentials of AA5083 was stable of -0. 58 V.