Influence of Sn, Cd, and Si addition on the electrochemical performance of Al–Zn–In sacrificial anodes

Abstract

Overcoming the reduction of current efficiency and stacking of corrosion products on the surface of Al–Zn–In sacrificial anodes after long‐term use is of great significance for Al–Zn–In alloy as an anode material for cathodic protection of steel structures in seawater. In this study, four different sacrificial anode materials were prepared based on the Al‐6Zn‐0.03In (wt%) alloy without and with the addition of alloying elements of Sn, Cd, and Si, respectively. The influence of the addition of Sn, Cd, and Si on the microstructure and electrochemical performance of the Al–Zn–In anode was investigated by optical microscopy and electrochemical measurements. The results show that the introduction of Sn, Cd, and Si changes the microdendrite structure of Al–Zn–In to equiaxed grain. The added Sn, Cd, and Si alloys have more negative and stable working potential and uniformly dissolved morphology. The actual capacity and current efficiency of aluminum alloys increase from 2,000.6 Ah/kg and 70.7% of Al–Zn–In alloy to 2,539.4 Ah/kg and 88.6% of Al–Zn–In–Sn, 2,437.3 Ah/kg and 85.5% of Al–Zn–In–Cd and 2,500.4 Ah/kg and 88.8% of Al–Zn–In–Si alloys, respectively.

Artificial neural network modelling to predict the efficiency of aluminium sacrificial anode

“…It is important to note that while preparing the dataset, we manually surveyed the literature pertinent to the current efficiency measurement of aluminium sacrificial anodes in different chemical compositions [1][2][3][4][5][6][7][8][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. We carefully checked the current efficiency, chemical composition, and other environmental factors in each paper, including pH, dissolved oxygen (DO), temperature, and pressure.…”

“…In recent years, the problem of forming a pure aluminium passive layer has been solved by adding elements such as Zinc(Zn), Indium(In). The role of these activator elements is to help the uniform dissolution of the anode and also prevent polarisation [1][2][3]. Moreover, Elements such as Titanium (Ti), Manganese (Mn), and Rare-Earth elements such as Lanthanum (La) and Gadolinium (Gd) have been used to improve the performance of sacrificial anodes [4][5][6][7][8].…”

Development of an Al-Zn-Bi alloy sacrificial anode for the protection of steel in artificial seawater: an electrochemical analysis

“…Al-Zn-Mg alloys are effective for cathodic protection; however, they have high hydrogen overpotential and form MgZn 2 intermetallic compounds, where the intermetallic acts as an anode and the aluminum matrix serves as the cathode, resulting in the fast dissolution of the sacrificial anode. On the other hand, Al-Zn-Mg-Mn alloys exhibit low protection efficiency, around 83% [21] Although, Al-Zn-Hg alloys demonstrate high current efficiencies, the environmental pollution caused by mercury led to its elimination from the competition [22]. Each sacrificial anode alloy system possesses its advantages and disadvantages, which determine its usage in specific environments.…”

Development of an Al-Zn-Bi alloy sacrificial anode for the protection of steel in artificial Seawater: An electrochemical analysis

“…On the other hand, Al-Zn-Mg-Mn alloys exhibit lower protection efficiency, around 83% [21]. Although Al-Zn-Hg alloys demonstrate high current efficiencies, the environmental pollution caused by mercury led to its elimination from competition [22]. Each sacrificial anode alloy system possesses its advantages and disadvantages, which determine its usage in specific environments.…”