When a wire mesh job needs stainless steel, the decision is almost always between grade 304 and grade 316. They look identical and share a similar feel, but a small difference in alloy chemistry changes how each resists corrosion, and that difference drives both performance and price.
What is 304 stainless wire mesh?
Grade 304 is the most widely used austenitic stainless steel, based on roughly 18% chromium and 8% nickel. The chromium forms a passive oxide layer that resists rust and many common chemicals, making 304 a strong general-purpose choice for indoor and many outdoor uses. It offers good formability and weldability, which is why 304 mesh is common in architecture, food handling, filtration and general fabrication where chloride exposure is limited.
What is 316 stainless wire mesh?
Grade 316 shares the austenitic structure of 304 but adds approximately 2-3% molybdenum. That molybdenum significantly improves resistance to pitting and crevice corrosion from chlorides, which is why 316 is favoured for marine, coastal, swimming pool, chemical processing and pharmaceutical environments. The trade-off is cost: the added alloying makes 316 typically more expensive than 304 for an equivalent mesh specification.
Side-by-side comparison
| Criteria | 304 stainless | 316 stainless |
|---|---|---|
| Key composition | ~18% chromium, ~8% nickel | Similar base plus ~2-3% molybdenum |
| Chloride / salt resistance | Good in low-chloride settings | Markedly better; resists pitting in salt and marine air |
| Chemical resistance | Broad general resistance | Stronger against many acids and aggressive media |
| Magnetism | Essentially non-magnetic when annealed; can gain slight magnetism after cold work | Similar; essentially non-magnetic when annealed |
| Typical use | Architecture, food, general filtration, indoor screens | Marine, coastal, chemical, pharma, pool and high-salt uses |
| Cost | Lower | Typically higher for equivalent mesh |
Which should you choose?
- Choose 304 for general-purpose, indoor or low-chloride applications where cost matters and corrosion exposure is moderate.
- Choose 316 for marine, coastal, swimming pool, chemical or salt-laden environments where chloride-driven pitting is a real risk.
- If in doubt for outdoor coastal use, the more conservative choice is usually 316, since premature corrosion can cost far more than the grade upgrade.
Salt, sea air or chemicals in the picture? Specify 316. General indoor or low-chloride use? 304 is usually enough.