深海低溶解氧环境下Al-Zn-In-Mg-Ti牺牲阳极性能研究

Performance of Al-Zn-In-Mg-Ti Sacrificial Anode in Simulated Low Dissolved Oxygen Deep Water Environment

对浅海中大量使用的Al-Zn-In-Mg-Ti牺牲阳极在深海低溶解氧环境下的性能进行了研究。通过恒电流法对Al-Zn-In-Mg-Ti牺牲阳极开路电位、工作电位、实际电容量、电流效率及溶解形貌等使役性能进行研究,并结合浸泡失重、动电位极化曲线、电化学阻抗谱、循环伏安等电化学方法以及SEM/EDS分析手段,探讨浅海现役Al-Zn-In-Mg-Ti牺牲阳极在深海低溶解氧环境下的电化学性能。结果表明:深海低溶解氧条件下,Al-Zn-InMg-Ti溶解速度减缓,活性元素的再沉积过程受到抑制,活化作用减弱,从而导致铝阳极表面氧化膜不易溶解,大量附着,造成其活化困难,放电性能下降,电流效率降低,阴极保护设计时需留出相应设计裕量。

The performance of the Al-Zn-In-Mg-Ti sacrificial anode,which is usually used in shallow sea area,was studied in a simulated deep-sea water of low dissolved oxygen via weight loss measurement,galvanostatic method,potentiodynamic polarization curves,electrochemical impedance spectroscopy and cyclic voltammograms test and scanning electron microscope(SEM/EDS),in terms of the open circuit potential,work potential,actual electric capacity,electric current efficiency and corrosion morphology of the Al-Zn-In-Mg-Ti sacrificial anode.It was found that,the dissolution rate of the Al-Zn-In-Mg-Ti sacrificial anode decreased in the simulated seawater of a low dissolved oxygen.The re-deposition process of the active elements was suppressed and the oxide scale on the anode surface was hard to be dissolved.Correspondingly,both the discharge performance and the current efficiency decrease,therefore a corresponding design margin should be set aside in the design course of cathodic protection.