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.
FAQ
Is the most corrosion-resistant material always the right choice? No. Titanium and PTFE resist corrosion extremely well but cost far more and can be harder to machine or fabricate than stainless steel, which is corrosion-resistant enough for most applications at a fraction of the cost. Match the resistance level to the actual environment, not the top of the list.
See the Corrosion Rate Calculator and the 316 Stainless Steel.