Research On The Influence Of Deep Sea Environmental Factors On Sacrificial Anode Dissolution

Sacrificial anode is the main means of material protection in marine environment.Al-Zn-In is the most widely used in the marine environment.However,the marine environment factors of hydrostatic pressure,oxygen content,temperature change in the deep sea,which leads to the deterioration of sacrificial anode discharge performance.In the paper,we explore the reasons of the deterioration of sacrificial anode and the effect of homogenization treatment on the properties of as-cast sacrificial anode.The activation process of Al-Zn-In sacrificial anode includes dissolving process and deposition process of activation element on the al anode.In the article we test the electrochemical performance of pure aluminium in the NaCl+activation's ion solution to explore the deposition process.we test the electrochemical performance of Al-Zn,Al-In,Al-Zn-In model alloy,comparing with the result of deposition.to explore the deposition process.and we can figure out the dissolution by comparing with the results of deposition process.We designed five different experimental conditions,and we analyzed the reasons of the deterioration of deep sea sacrificial anode through comparing the results of different experimental conditions.The results show that the increasing of hydrostatic pressure has no influence on dissolution of the activation's ion,but it inhibits ion deposition process and activation effect.The reduction of temperature reduces the electrode reaction rate,and it inhibits the dissolution and the deposition process.The reduction of oxygen content inhibits the dissolution of activation ions,which makes the contents of In3+ reduction.Even though the reduction of oxygen content will promote the deposition of activation ions,the total content of activation ions decreases.So the amount of deposition ions drop off,and its effect been affected.The main reason of performance deterioration is decrease of oxygen content.The results confirm the Zn and In which is in the Al-Zn-In bas the synergistic interaction.The activation effect of Zn is that it can promote the dissolution of Al and In.The In3+ which In transforms deposits on the electrode.The progress of that can accelerate the separation of the oxidation film and matrix.The effect of In is the deposition process.The casting process will cause dendritic segregation,and we find that we can eliminate it by annealing treatment.But it can't improve the discharge capacity of Al-Zn-In in the deep sea.