Corrosion Current Density
The current flowing per unit area during corrosion measures the rate of rusting.
Physicochemical Mechanism of Action
Corrosion current density is the electric current flowing through an electrolyte layer (e.g., iron layer) that causes corrosion. It is proportional to the number of resulting ions and the electric field.
Metallurgical Relevance & Welding Risks
A high corrosion current density can cause rapid rusting and wear of steels, shortening component life. It also increases the risk of electrolytic corrosion (ECC), especially in humid environments or when dissimilar metals are in direct contact.
Workshop Practice & Action Instructions
To reduce corrosion current density:
• Clean the steel surface thoroughly before welding.
• In humid conditions, use a sealant or anti-corrosion film.
• Avoid direct metal-to-metal contact by separating with insulating material.