Mil-Spec Zinc and Mil-Spec Aluminum anodes provide excellent corrosion protection
for steel and aluminum hull vessels that operate in salt or brackish water. Both are
very effective. Zinc anodes have traditionally been less expensive than those made
with aluminum, but that's no longer the case. Aluminum anodes are now less expensive than their zinc counterparts, making them a clear favorite for most commercial applications.
The difference between zinc and aluminum anodes is summarized below:
| |
Zinc
MIL-A-18001K |
Aluminum
Mil-A-24779(SH) |
Voltage (1) |
-1050 mV |
-1100 mV |
| Density |
0.258 lbs per cubic-inch |
0.105 lbs per cubic-inch |
| Energy Capacity |
368 amp-hours per lb |
1150 amp-hours per lb |
| Service Life (relative to Zinc) |
100% |
120% |
| Cost (relative to Zinc) |
100% |
80% |
(1) Galvanic voltage produced relative to a silver/silver-chloride electrode in salt water |
|
