The authoritative public forum
  for Metal Finishing since 1989
-----

Sacrificial anode

2003

Dear sir,

How are you? Is it possible to add Sn, Cu, Ag, one type to commercial aluminum (99.7%) by using Immersion plating technique to obtain sacrificial anode more excellent behaviors.

Thank you,

Best regards,

Almangush
Alfro - Tripoli, Libya

---

If you mean will Sn, Cu or Ag act as a sacrificial anode on aluminium, no it will not. However, if you mean, can you use Sn, Cu or Ag as a cathode to promote the dissolution of aluminium to act as a sacrificial anode, then it depends what it is attached to. For a sacrificial anode to work it must be in electrical contact with another metal that is cathodic to it (and that is most metals in common use!). However, if you attach this third metal to Cu, Sn or Ag, it is possible that the other metal may become anodic itself. The presence of alloying metals in aluminium will often improve the corrosion resistance of aluminium, so it is best to use as pure aluminium as possible.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003