Corrosion Flashcards
What is corrosion?
It’s the gradual destruction of metals due to chemical reactions between metals and the oxygen and water around them.
What chemicals cause corrosion?
oxygen and water.
What’s an example of corrosion?
Iron rusting.
Iron only rusts when…
It’s exposed to water AND oxygen.
What is the process by which iron rusts and there is an addition of oxygen to the iron atoms?
The process is called oxidation.
What are the three methods we can use to prevent corrosion?
The sacrificial method, the coating method, and the galvanizing method.
What are physical barriers to oxygen and water that prevent corrosion?
Painting, greasing, or electroplating?
What is electroplating?
Electroplating is the process of applying a metal coating on another piece of metal.
How does electroplating prevent corrosion?
Electroplating improves the corrosion resistance of metal objects, this prevents corrosion from happening.
How does greasing prevent corrosion?
Greasing allows a physical barrier between the metal and oxygen & water, this prevents corrosion from happening.
How does painting prevent corrosion?
The painting covers up the spots that are exposed to air and water, this prevents corrosion from happening.
What is galvanizing?
Galvanizing is when a metal is sprayed with a metal that is more reactive than it is.
How does galvanizing prevent corrosion?
The spray is used as a coating, this coating forms a barrier that prevents corrosive substances from reaching the metal.
What happens if the more reactive metal gets damaged during the galvanizing process?
If the more protective metal gets damaged, it will continue to protect the metal as a sacrificial metal.
What is galvanizing? (shorter definition)
Galvanizing is a hybrid of coatings and the sacrificial method.
