铝合金牺牲阳极深海应用性能研究

Performance of Aluminium Sacrificial Anodes in Deep Sea

目的评价铝合金牺牲阳极在深海环境的电化学性能。方法通过利用中国船舶重工集团公司第七二五研究所深海试验技术和装置,原位测量三种铝合金牺牲阳极在南海1200 m深海环境的电化学性能。结果三种阳极在1200 m深海环境下的开路电位均在?1.17 V左右,工作电位在?1.11～?0.91 V范围内。1#和2#阳极的实际电容量小于2400A?h/kg,电流效率约为80%,表面存在明显的优先溶解和晶粒脱落现象,表面腐蚀产物有结壳现象发生。3#阳极的实际电容量约为2500A?h/kg,电流效率大于85%,表面微观溶解形貌相对均匀,但表面存在大面积未溶解区域,且腐蚀产物不易脱落。结论该研究结果为深海工程装备阴极保护设计提供了支撑。

Objective To evaluate electrochemical properties of aluminum alloy sacrificial anode in the deep sea environment. Methods In this paper, electrochemical properties of three kinds of aluminum sacrificial anode in the South China Sea with 1200 m depth were measured with deep sea testing technique and equipment of State Key Laboratory for Marine Corrosion and Protection, Luoyang Ship Material Research Institute. Results The open circuit potential was about -1.17 V (vs Ag/AgCl) and the working potential was in the range of -1.11 to -0.91 V when the three anodes were in a deep sea environment of 1200m. The practical current capacity of 1# and 2# were both below 2400 A·h/kg and current efficiency were about 80%, and their dissolution morphologies were not uniform and corrosion product deposited on the surface. The practical current capacity of 3# was about 2500 A·h/kg and the current efficiency was more than 85%, however there was large undissolved area and corrosion productions adherent to the anode surface. Conclusion The study result provides supports for cathodic protection design of deep-sea engineering equipment.