Magnesium Anode (Circular Type)

Circular Magnesium Anode: Superior corrosion protection for underground steel structures in medium to high resistivity soil.



Magnesium anodes serve as a popular solution to combat corrosion in situations where applying impressed current cathodic protection isn’t practical or viable for the specific infrastructure.

For soil applications, naked magnesium anodes are widely favored. Their pronounced negative potential generates a robust driving force, enabling them to effectively shield subterranean steel structures in soils with moderate to high resistivity levels (1,000 – 10,000 Ω·cm).

Our naked magnesium anodes are typically crafted into two variants with distinct electrode potentials compared to a Cu/CuSO4 reference electrode. These variations cater to a broad spectrum of buried metallic structures across different soil resistivities. The high-potential magnesium anodes excel in arid or resistant earth conditions or situations necessitating heightened current due to poorly coated tanks. Conversely, the standard-potential magnesium anodes demonstrate remarkable performance in corrosive soils, especially when tanks are adequately coated, ensuring a longer lifespan compared to the high-potential alloy.

Quality Substrate Material

Our magnesium anode is produced following the ASTM B843-M1C specification for high-potential anodes or ASTM B843-AZ63B specification for standard-potential anodes, based on the composition outlined below:

Element High Potential (ASTM B843 – M1C) Standard Potential (ASTM B843 – AZ63B)
Aluminum (Al) 0.01% 5.3 – 6.7%
Manganese (Mn) 0.5 – 1.3% 0.15 – 0.7%
Zinc (Zn) 2.5 – 3.5%
Silicon (Si) 0.05% 0.1%
Copper (Cu) 0.02% 0.02%
Nickel (Ni) 0.001% 0.002%
Iron (Fe) 0.03% 0.003%
Other Each 0.05%
Others Total 0.3% 0.3%
Magnesium (Mg) Remainder Remainder


Different Electro-potential Options

Two types of cast magnesium anodes are commonly available:

1. Conventional Magnesium Alloy Anode

A standard-potential anode exhibits a nominal corrosion potential of around -1.55 volts (compared to a Cu/CuSO4 reference electrode). It proves effective in soil environments where resistivity remains below 20 Ω·cm.

2. Enhanced Potential Magnesium Alloy Anode

High-potential magnesium anodes boast elevated open-circuit voltage and driving potential. They demonstrate an open-circuit potential ranging from negative 1.7 to 1.75 volts, representing a 20% to 30% increase over traditional magnesium anodes. This higher potential translates to increased current output and improved efficiency, offering ample cathodic protection while reducing anode consumption. These anodes are particularly suitable for structures situated in soils with resistivities surpassing 2,000 Ω·cm or for structures facing significant corrosion challenges.

Technical Measurement High Potential Standard Potential
Open Circuit Potential (-V) 1.7 ~ 1.75 1.5 ~ 1.55
Close Circuit Potential (-V) 1.58 ~ 1.62 1.45 ~ 1.50
Min. Current Capacity 500 A.h/lbs (1100 A.h/kg) 550 A.h/lbs (1230 A.h/kg)
Min. Current Efficiency 50% 55%

Remarks: Open/close circuit potential is with respect to a Saturated Calomel Reference Electrode.

Measured Electrical Efficiency Curve of Bare Magnesium Anode 750x500 1

Strict Quality Control

Adhering to ISO 9001:2015 guidelines, our anodes undergo manufacturing, inspection, and testing processes that adhere to rigorous quality control protocols, guaranteeing optimal performance levels.


We employ ISO 9001:2015 quality management system and rigorous internal testing standards to ensure the optimum lifespan and performance of our anodes. Each anode is labelled with a unique serial number for quality tracking.

Technical Measurement Chemical Composition Electrochemical Performance Physical Properties
Testing Standard ATSM A518 (Gr1) ATSM A518 (Gr3) Foundry ITP
Testing Content Chemical Analysis Circuit Potential / Anode Resistance / Current Efficiency Surface Finish / Dimension & Weight / Steel Core / Cable Connection / Sealing / Backfill Packaging
Equipments Optical Emission Spectrometer OBLF QSN 750 Electrochemical Analyzer EPI 200 Calibrated Digital Measuring Devices