Guidelines for how best to keep copper and aluminum apart to avoid corrosion?
In many industrial installation use of aluminium and copper combination can not be ruled out completely.
To minimize galvanic corrosion, always attempt to maximize the size of the anode and minimize the
size of the cathode. In an aluminum/copper couple, copper is the cathode and aluminum is the anode. If
you paint the copper and the paint gets scratched, then you have a small cathode and a very large anode
which is exactly what you want. We must know that in a cathode-anode combination, larger is the anodic area lesser will be the corrosion rate.
On the other hand If you paint the aluminum and it gets scratched, then you have a small anode and a very large cathode, which is not what you want.This will accelerate the corrosion rate.
In many industrial installation use of aluminium and copper combination can not be ruled out completely.
To minimize galvanic corrosion, always attempt to maximize the size of the anode and minimize the
size of the cathode. In an aluminum/copper couple, copper is the cathode and aluminum is the anode. If
you paint the copper and the paint gets scratched, then you have a small cathode and a very large anode
which is exactly what you want. We must know that in a cathode-anode combination, larger is the anodic area lesser will be the corrosion rate.
On the other hand If you paint the aluminum and it gets scratched, then you have a small anode and a very large cathode, which is not what you want.This will accelerate the corrosion rate.
No comments:
Post a Comment