Which term describes electrochemical corrosion caused by dissimilar metals in an electrolyte?

• A. Galvanic Corrosion
• B. Impedance
• C. Green Strength
• D. Lite

Answer: (A)

Galvanic corrosion describes electrochemical corrosion that happens when two different metals are in electrical contact in an electrolyte. Because the metals have different electrode potentials, electrons flow from the more active metal (the anode) to the less active metal (the cathode) through the metal connection, while ions move through the electrolyte. This makes the active metal corrode faster while the noble metal is protected at the cathode. The effect is stronger in a good electrolyte (like saltwater or damp conditions) and when there’s a large surface area of the active metal relative to the metal being protected. To prevent it, separate dissimilar metals with insulation, apply coatings, use sacrificial anodes, or choose metals with similar electrochemical potentials.

Impedance is about resistance to current flow, not corrosion; Green Strength relates to material strength during or after curing; Lite isn’t a relevant term here.