KBA: Understanding Galvanic Reaction

[Jason Essary]

What is Galvanic Reaction?

 

- When two dissimilar metals are in contact and exposed to an electrolyte substance it causes one of the metals to lose ions and slowly consumes that metal.

 

- It works much like a battery. One of the metals will become and act like an Anode(Negative) and the other a Cathode(Positive). This process will slowly consume the Anode and actually strengthen the Cathode.

 

- Galvanic reaction occurs when an electrolyte combines with water. Depending on which electrolyte is present, it will completely(strong) or partially (weak) ionize with the water to form a strong or weak electrolyte substance.

 

What is an electrolyte substance?

Strong Acids

Examples: Hydrochloric Acid, Sulfuric Acid, and other Acids

Strong Bases

Examples: Sodium Hydroxide, Calcium Hydroxide, and other Hydroxides.

Salts

Sodium Chloride

Winter Road Treatment:

 

- Different cities utilize a handful of different chemicals to treat roadways for ice. Most of these are from a form of chloride which does become an electrolyte once dissolved with water.

 

TIP: It is always a good idea to clean these chemicals from any vehicle and/or camper when possible.

 

What type of impact does this play on Aluminum? 

 

- When oxygen is present (in water), aluminum naturally reacts to form aluminum oxide and this is the key to its ability to resist corrosion. Unless exposed to a substance or condition in which destroys the protective layer, aluminum will remain resistant to corrosion.

 

- When aluminum contacts another metal(steel for example), it sets in place the possibility of a galvanic reaction if an electrolyte substance comes in contact with the metals.

 

What does Oliver do to prevent this natural process?

A protective layer, cavity spray, is placed between the two metals.

Zinc anodes are attached to the aluminum frame

The Zinc becomes the anode part of the equation and if the galvanic reaction process takes place, it will consume the Zinc anode instead of the aluminum frame.

How often should I check my Anodes?

 

- Depending on where you live or where you travel you may or may not even have a galvanic reaction but it is still a good idea to inspect your anodes at least once a year and more if you start to notice that the anode is deteriorating.