304 is the workhorse austenitic stainless steel, an 18 chromium 8 nickel alloy that balances corrosion resistance, formability, weldability and cost better than any other grade. If a part needs stainless and nothing in the environment or the loading argues otherwise, 304 is usually the starting point.
304L lowers carbon to limit chromium carbide precipitation during welding, which protects corrosion resistance in the heat affected zone of welded assemblies that will not be solution annealed afterward. 304B adds boron for neutron absorption in nuclear storage and shielding applications.
We stock 304, 304L and 304B as bar, plate, sheet, tube and wire, with cutting, blanking and finishing to your requirement.
Sizes and stock
- Round, square, hex and flat bar 0.125" through 16"
- Sheet and strip from 0.002" foil gauge through 0.250"
- Plate 0.187" through 6", discs and rectangular blanks
- Seamless and welded tube, plus wire and coil
Processing capabilities
- Condition and precipitation hardening (H900 through H1150) to your call-out
- Shearing, waterjet, laser and saw cut blanks
- Centerless grinding, turning and polishing
- Penetrant dye and ultrasonic inspection, chemical assay and physical testing
Specifications
Material is released to the applicable specification with mill test reports and, on request, independent lab verification.
Why engineers specify 304
- Excellent general corrosion resistance in a wide range of environments
- Highly formable and readily welded
- Non magnetic in the annealed condition
- Broadest product form availability of any stainless grade
Nominal chemistry
Percent by weight, nominal composition per the governing specification. The mill test report for your heat is the controlling document.
Typical mechanical properties
| Condition | Tensile strength | Yield strength | Elongation | Hardness |
|---|---|---|---|---|
| Annealed | 75 ksi min | 30 ksi min | 40% min | 201 HBW max |
| 304L annealed | 70 ksi min | 25 ksi min | 40% min | - |
Typical published values for reference only, not for design. Properties vary with section size, product form and processing. Order to the specification and condition your drawing requires.
Typical applications
- Process piping, tanks and pressure vessels
- Food, dairy and pharmaceutical equipment
- Architectural and structural trim
- Fasteners and general machined hardware
Fabrication notes
Machining
Austenitic grades work harden quickly, so use positive rake tooling, rigid setups, generous feed and flood coolant rather than light dwelling cuts. Martensitic and precipitation hardening grades machine most easily in the annealed or solution treated condition and are aged after rough machining.
Welding
Weldable by GTAW, GMAW, resistance and electron beam methods with matching or over alloyed filler. Stabilized and low carbon grades resist sensitization in the weld zone. Precipitation hardening grades are normally welded in the solution treated condition and aged afterward.
Forming
Sheet and strip form well in the annealed condition; cold worked tempers trade formability for strength. Allow for springback and, where specified, an intermediate anneal between draws.
304 compared with similar grades
316 / 316L
Adds molybdenum for better pitting resistance in chloride environments.
321
Titanium stabilized for welded service at elevated temperature.
303
Free machining version for high volume turned parts, with reduced corrosion resistance.
Designations and cross reference
- Material family
- Stainless Steel
- Werkstoff (W.Nr)
- 1.4301
- EN designation
- X5CrNi18-10
- Series
- 300 Series
Working from an obsolete, foreign or superseded designation? Send it over and we will cross reference it to a current grade and specification.
Quality, testing and traceability
Supplied with mill test reports and heat traceability, with penetrant dye, ultrasonic, chemical assay, hardness, corrosion and mechanical testing available on request.
We are AS9100D and ISO 9001:2015 registered. If our stock does not already carry the inspection your specification requires, we can quote the material with that work performed. More on our quality system
Available forms
304 frequently asked questions
What is 304?
304 is the workhorse austenitic stainless steel, an 18 chromium 8 nickel alloy that balances corrosion resistance, formability, weldability and cost better than any other grade. If a part needs stainless and nothing in the environment or the loading argues otherwise, 304 is usually the starting point.
What forms is 304 available in?
We supply 304 in bar, billet, casting, extrusion, fitting, flange, foil, forging, pipe, plate, profile, rod, sheet, strip, tube, wire. Custom sizes are converted from billet, and we can provide saw cut, waterjet or near net blanks so material arrives closer to your finished part.
What is the UNS or equivalent designation for 304?
304 is designated Werkstoff 1.4301, EN X5CrNi18-10. If your drawing calls out an obsolete or foreign designation we can cross reference it and confirm the equivalent before you order.
What specifications can 304 be supplied to?
Commonly ordered specifications include AMS 5513, AMS 5560, AMS 5563, AMS 5564, AMS 5565, AMS 5566. Material is released to the specification and condition on your purchase order, with mill test reports supplied as standard.
What conditions can 304 be ordered in?
We can supply Annealed, 304L annealed. If our stock is not already in the condition you need, we can quote it with the heat treatment performed before shipment.
Can you cut 304 to size?
Yes. Saw cutting, waterjet, laser and shearing are available, along with trepanning, gun drilling, lathe turning and CNC machining, so you can order blanks or rough machined pieces rather than full lengths.
Do you provide test reports and additional testing on 304?
Every order ships with mill test reports and heat traceability. If your print calls for ultrasonic inspection, penetrant dye, magnetic particle, chemical assay, micrography, hardness or mechanical testing and our stock does not already carry it, we can quote the material with that work performed.
Can 304 be supplied to DFARS domestic melt requirements?
Tell us at quote stage if the order is DFARS or domestic melt restricted and we will confirm availability against that requirement before you commit.
What do you need to quote 304?
Grade, form, dimensions, quantity, specification and condition, plus any testing or certification requirements and the date you need it. Send a drawing if you have one. Quotes are typically ready within 24 hours.
How does 304 compare with 316 / 316L?
Adds molybdenum for better pitting resistance in chloride environments.