These materials resist corrosion best, ranked from most to least resistant. Titanium and inert plastics top the list, while plain steel sits at the bottom.
| Material | Corrosion resistance |
|---|---|
| Titanium | Outstanding, even in seawater |
| PTFE | Chemically inert |
| 316 Stainless | Excellent, resists chlorides |
| 304 Stainless | Very good |
| Bronze | Excellent in marine use |
| Copper | Good, forms a protective patina |
| Aluminum | Good, self-passivating |
| Carbon Steel | Poor, rusts without protection |
Stainless steels and aluminum protect themselves with a thin passive oxide layer, while titanium and fluoropolymers are nearly immune to most environments.
Match the metal to the environment. For saltwater and chemicals, reach for titanium, 316 stainless, or inert plastics. Carbon steel and cast iron need coatings or they will rust.
See the Corrosion Rate Calculator and the 316 Stainless Steel.