Material datasheet · Austenitic stainless
Stainless Steel 304
UNS S30400 · Solution annealed (~1900–2050°F, water quench)
The general-purpose austenitic stainless — 18/8. Corrosion-resistant, weldable, ubiquitous; slightly easier to cut than 316L.
Chemical composition
Nominal % by weight.
| Element | % by wt |
|---|---|
| Fe | Bal. |
| Cr | 18.0–20.0 |
| Ni | 8.0–10.5 |
| Mn | ≤2.0 |
| Si | ≤1.0 |
| C | ≤0.08 |
Applicable specifications
AMS / ASTM / MIL.
- AMS 5513 (sheet/strip/plate)
- AMS 5639 (bar/wire/forgings)
- ASTM A276
- ASTM A479
- ASTM A240
Machining guidance
CNC parameters and tooling.
Coated carbide, sharp positive rake; avoid dwelling
Work-hardens aggressively but a touch easier than 316L — no molybdenum means cleaner chips and ~10–20% higher SFM. Sharp tools, deep DOC, constant feed; never rub. 303 (sulfur) or 304L-F free-machining variants cut faster but trade corrosion resistance.
Stock & cost
Forms and Q1 2026 pricing.
- Passivate (ASTM A967, AMS 2700) — coordinated outside
- Electropolish — coordinated outside
- Bead blast (matte)
- No.4 / brushed finish
Typical applications
Where 304 Stainless is the right pick.
- Food & beverage equipment
- Architectural hardware
- Fasteners
- Fabricated weldments
- Sinks & enclosures
Alternative materials
Substitute or upgrade options.
- 316L (more Mo, better Cl⁻ / marine resistance)
- 303 (free-machining, lower corrosion)
- Duplex 2205 (higher strength)
True Precision Machining · Buellton, CA
Machine your part in 304 Stainless.
5-axis CNC · ISO 9001 · AS9100 · ITAR · CMMC-compliant · DFARS-compliant supply chain. AS9102 FAI on aerospace.
Technically reviewed by the True Precision Machining engineering team · Last reviewed June 2026
Standards referenced: AMS 5513 (sheet/strip/plate), AMS 5639 (bar/wire/forgings), ASTM A276, ASTM A479, ASTM A240
Keep exploring
Related tools & references
Speeds, feeds, tooling, and chip strategy.
SFM, RPM, and feed rate for this material.
Compare alloys by strength, weight, temperature, and cost.
Estimate part weight from 304 Stainless stock.
Aerospace specs that call out this alloy.