腐蚀性及材料因素影响的规律
(北京有色金属研究总院， 北京 100088)
摘 要: 通过铝镁合金在我国青岛、 厦门、 榆林各海域海水经16a及短期海水的腐蚀实验结果， 分析了我国海域海水腐蚀行为的主要规律： 厦门海域的海水对铝镁系防锈铝合金构成相对苛刻的腐蚀环境。不同防锈铝合金的耐蚀性能不同， 且其腐蚀行为与不同的海水环境因素密切相关， 使用不同的防锈铝合金来评定各海域海水腐蚀性， 所得的排序不同。 合金不同表面状态对海水腐蚀行为的影响依海域及合金而异，在腐蚀性较强的海水中， 不同浓度酸洗状态带来的腐蚀行为差异可被逐步加大， 但对不同海域海水腐蚀性的评定未构成大的影响。 原始出厂态的耐蚀性能受合金类型及其原始表面膜质量的影响，其用于评定海水腐蚀性会比酸洗态带来更多不确定因素。 杂质等缺陷的存在增大了点蚀发生的随机性, 也给腐蚀性的评定带来一定的干扰。
关键字: 海水腐蚀性； 防锈铝合金； 表面状态； 点蚀深度
by material factors
（General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:Two Al-Mg alloys were immersed into seawater in Qingdao, Xiamen and Yulin sea areas for long term and shorter term. The results show that the corrosivity of seawater in Xiamen sea area to Al-Mg alloys is relatively serious. Different results can be obtained using the corrosivity evaluation of seawater to different Al-Mg alloys because the corrosion resistance of the alloys is different each other and their corrosion behaviors are sensitive to different seawater environment factors. The influence of alloy surface conditions on the corrosivity of seawater changes with different sea areas and alloys, and the difference of corrosion behaviors can be increased gradually. But this does not influence the corrosivity evaluation of seawaters too much. The alloy defects increase the randomness of pitting occurring and interference to the corrosivity evaluation.
Key words: seawater corrosivity; Al-Mg alloys; surface conditions; pitting depth
