Define area effect regarding galvanic corrosion?
A. cathodic area * anodic area
B. anodic area/cathodic area
C. cathodic area/anodic area
D. cathodic area + anodic area
This question was posed to me in a national level competition.
My question is based upon Eight Forms in portion Eight Forms of Corrosion of Corrosion Engineering
Correct option is C. cathodic area/anodic area
To explain I would say: It is the ratio of cathodic to anodic areas. An unfavorable area ratio with a large cathodic area and small anodic area results in high current density at the anode. The greater the current density at an anodic area the greater the corrosion rate.