Quote:
Originally Posted by KegRiver
Yes I do, do you? Anodes erode, not corrode.
Erode is to carry away, corrode is to destroy by chemical action.
The metal in an anode is carried away by electricity generated by chemical action. Much like electroplating, a very similar chemical reaction.
Corrosion changes the chemical structure of a substance, erosion simply removes a substance slowly, one molecule at a time.
Corroded aluminum still exists but in an altered state, IE; aluminum oxide.
Which adheres to the parent metal.
Eroded zinc from an anode still exists as zinc, but as particles of zinc in solution, not part of or attached to the parent metal.
At least that is what my text books said. Being that I am not a chemist nore an engineer, I can only take the text as truth since I have no other source of information.
If you have texts that say otherwise I would appreciate knowing what texts those are so I can correct the lessons I was taught.
|
Corrosion is a chemical reaction, while erosion is a physical action. What you described is a chemical reaction and therefore corrosion.
this simplifies the explanation of how an Anode works and please note that the metal used in an anode is molecular weaker than the metal it is protecting, thus it corrodes first.
Sacrificial anodes are used to protect metal structures from corroding. Sacrificial anodes work by oxidizing more quickly than the metal it is protecting, being consumed completely before the other metal reacts with the electrolytes