Short answer: Choose 304 stainless steel for general food equipment, indoor fabrication and mildly corrosive service. Choose 316 when chloride exposure, coastal air, salt, aggressive cleaning chemicals or a higher corrosion margin justifies the added molybdenum and cost.
This guide is written for stainless steel buyers, sourcing teams, engineers and product manufacturers. The purpose is not to declare one universal winner, but to turn a broad material question into a specification that a mill or service center can quote, process and inspect consistently.
Quick Comparison
| Option | Key point | Typical use or decision |
|---|---|---|
| 304 / S30400 / EN 1.4301 | General-purpose austenitic grade | Cookware, tanks, appliances, interior fabrication |
| 316 / S31600 / EN 1.4401 | Molybdenum-bearing grade with stronger pitting resistance | Coastal equipment, chemical handling, medical and marine-adjacent products |
The table is a starting point. Actual performance depends on the governing standard, delivered condition, dimensions, surface finish, fabrication route and service environment. Commercial names should never replace a complete purchase specification.
What Buyers Should Evaluate
- Define chloride concentration, temperature and cleaning chemistry before selecting a grade.
- Do not treat 316 as corrosion-proof; crevices, deposits and poor finish still matter.
- Compare total life-cycle cost, not only the price per tonne.
For production orders, share the end use rather than requesting a grade or finish in isolation. A supplier can then review corrosion exposure, forming severity, welding, visual requirements and packing before material is cut. This early review is usually less expensive than correcting a rejected shipment or unstable production trial.
Common Purchasing Mistakes
- Selecting 304 for persistent salt exposure because the product is only used outdoors
- Buying 316 without chemical verification or an MTC
- Ignoring weld cleanup and surface roughness
These mistakes are avoidable when drawings, approved samples, inspection methods and certificate requirements are agreed before production. For visual products, retain a signed master sample. For functional dimensions, define where and how measurements will be taken.
Recommended RFQ Wording
State grade, standard, product form, dimensions, finish, edge, tolerance, quantity and certificate requirement. For chloride service, include the actual exposure and cleaning cycle (the stainless steel RFQ checklist lists every field to send).
Also include order quantity, acceptable quantity variation, destination, required delivery date and whether partial shipments are allowed. If a requirement is critical, make it measurable and place it on the purchase order rather than only in an email conversation.
How Still Steel Supports the Project
Still Steel supplies stainless steel coil, strip and sheet and provides slitting, cut-to-length, brushing, polishing and protective-film services. We can compare available mill material with your drawing, prepare trial quantities and preserve heat-number traceability through service-center processing.
Send the grade, dimensions, annual volume and application to vip@still-steel.com, or discuss the requirement on WhatsApp.
Frequently Asked Questions
Is 316 always better than 304?
No. 316 provides a larger corrosion margin in chloride-bearing environments, but 304 is often the more economical and fully adequate choice for mild service.
Can 304 be used outdoors?
Yes in many rural and urban environments, provided the design drains well and the surface is cleaned. Coastal or heavily polluted sites require a more careful review.
Why is 316 more expensive?
316 contains molybdenum and typically more nickel than 304. Alloy surcharges and market prices therefore make it more expensive.
Technical References
Reference documents support general selection and fabrication principles. The final material decision must follow the applicable contract, standard, regulation and engineering review for the specific product.