论文部分内容阅读
采用恒电流试验评价了不同Ga含量的Al-Ga二元合金牺牲阳极的电化学性能,并通过X射线衍射、扫描电镜及能谱分析、回沉积等实验探讨了阳极的活化溶解机制。结果表明,采用高纯铝锭炼制的Al-0.07%Ga二元合金工作电位在-0.820 V～-0.876 V(vs.Ag/AgCl海水)之间,而用工业铝锭Al99.85炼制的Al-0.1%Ga二元合金阳极工作电位在-0.802 V～-0.818 V之间,基本满足低驱动电位牺牲阳极的要求,但局部腐蚀溶解均较严重,溶解性能有待改善;Al-Ga合金腐蚀产物中的Ga含量随基体中Ga含量的增加而增加,但远小于基体中的Ga含量;溶解后阳极表面的Ga含量大于基体中Ga含量,原因是溶解在溶液中的Ga~(3+)回沉积到阳极表面,使得阳极表面Ga含量增加;Al-Ga阳极的活化符合溶解-再沉积机理。
The electrochemical properties of Al-Ga binary alloy sacrificial anodes with different Ga contents were evaluated by constant current test. The mechanism of activation and dissolution of the anode was discussed by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and back deposition. The results showed that the working potential of Al-0.07% Ga binary alloy refined by high purity aluminum ingot ranged from -0.820 V to -0.876 V (vs. Ag / AgCl seawater), while industrial aluminum ingot Al99.85 Of Al-0.1% Ga binary alloy anode potential between -0.802 V ~ -0.818 V, basically meet the low driving potential sacrificial anode requirements, but the partial corrosion dissolution are more serious, the solubility to be improved; Al-Ga alloy The content of Ga in the corrosion products increases with the increase of Ga content in the matrix, but it is much smaller than that in the matrix. The content of Ga in the surface of the anode after dissolution is larger than that in the matrix because Ga ~ (3+ ) Back to the anode surface, making the anode surface Ga content increased; Al-Ga anode activation in line with the dissolution - redeposition mechanism.