Definition - What does Exfoliation Corrosion mean?
Exfoliation corrosion is a form of intergranular corrosion which involves selective attack of a metal at or adjacent to grain boundaries. In this process, corrosion products formed force metal to move away from the body of the material, giving rise to a layered appearance.
Exfoliation corrosion is also known as layer corrosion or lamellar corrosion.
Corrosionpedia explains Exfoliation Corrosion
This type of corrosion occurs on the extended grain boundaries. The products of corrosion force the material to move away from the body, so these products occupy a greater volume than the volume of the parent metal, thus causing the metal to exfoliate or delaminate.
Aluminum alloys, especially those containing copper or zinc-magnesium-copper as alloying constituents are susceptible to this type of corrosion.
Methods for preventing exfoliation corrosion include:
- Coating the material
- Selecting a more exfoliation-resistant aluminum alloy
The Corrosion Properties of Aluminum and Its Alloys