304L Stainless Steel
304L stainless steel is a low-carbon version of 304, developed for welded structures where stable corrosion performance is required. It is widely used for welded tanks, pipelines, pressure equipment, and hygienic fabrication.
- Welded tanks and vessels for food and process industries
- Welded piping systems and general plant fabrication
- Architectural structures that require clean appearance and durability
- Projects that require reliable weld quality without complex heat treatment plans
- Low carbon helps reduce weld-related intergranular corrosion risk
- General corrosion resistance is similar to 304 in many environments
- For coastal or chloride-rich exposure, 316L is often evaluated
- For high-temperature stabilization needs, 321 may be reviewed
304L is often specified when the design includes welding and the project wants a wider safety margin against weld-related corrosion. The key difference is carbon control, which helps reduce carbide precipitation in the heat-affected zone.
In procurement terms, 304L is a practical grade for welded tanks, process piping, and general fabrication where corrosion resistance, cleanability, and stable weld performance are part of the requirement.
| Standard system | Designation |
|---|---|
| ASTM / AISI | 304L |
| UNS | S30403 |
| JIS | SUS304L |
| EN (W.-Nr.) | 1.4307 |
| DIN symbol | X2CrNi18-9 |
| GOST | 03Х18Н11 |
| GB | 00Cr19Ni10 |
Values vary slightly by standard and product form. Confirm your required limits in the purchase specification.
| Grade | Reference | C | Cr | Ni | Mn | Si | P | S | N | Fe |
|---|---|---|---|---|---|---|---|---|---|---|
| 304L / S30403 | ASTM A240 (typ.) | ≤0.03 | 18.0–20.0 | 8.0–12.0 | ≤2.0 | ≤0.75 | ≤0.045 | ≤0.03 | ≤0.10 | Balance |
| 1.4307 | EN 10088 (typ.) | ≤0.03 | 17.5–19.5 | 8.0–10.5 | ≤2.0 | ≤1.0 | ≤0.045 | ≤0.03 | ≤0.10 | Balance |
| SUS304L | JIS G4304 / G4305 (typ.) | ≤0.03 | 18.0–20.0 | 9.0–13.0 | ≤2.0 | ≤1.0 | ≤0.045 | ≤0.03 | — | Balance |
| Grade | Condition | Tensile strength | Yield strength | Elongation | Hardness |
|---|---|---|---|---|---|
| 304L / S30403 | Annealed | ≥ 485 MPa | ≥ 170 MPa | ≥ 40% | ≤ 201 HB (≈ 92 HRB) |
| 1.4307 | Annealed | 500–700 MPa | ≥ 200 MPa (proof) | ≥ 45% | ≤ 215 HB |
If your drawings use different hardness scales, use the Hardness Conversion page to align inspection reporting.
- Weld-focused grade: low carbon reduces sensitization risk in many welded structures.
- Reliable general corrosion resistance: similar to 304 in many atmospheric and industrial environments.
- Good formability: suitable for bending, stamping, and deep drawing with correct tooling.
- Clean surface options: common finishes support hygienic equipment and visible parts.
- Service limit: for marine or high chloride exposure, 316L is often evaluated.
304L is commonly selected for TIG and MIG welding as well as resistance welding in many fabrication lines. The low-carbon design supports stable corrosion performance near the weld in many service conditions.
304L offers strong ductility for bending and drawing. In production, plan for work hardening and springback when tight tolerances are required.
Machinability is generally moderate and similar to 304. Use sharp tools and stable feeds to reduce work hardening.
Oxidation resistance is commonly referenced to about 870°C for intermittent service and about 925°C for continuous service, subject to design limits and environment.
304L is available across flat products, tubular products, and long products. Provide your standard, size, finish, quantity, inspection requirement, and destination port for an executable offer.
Thickness: 0.3–6.0 mm
Thickness: 3–100 mm
Thickness: 0.3–6.0 mm
Thickness: 3–14 mm
Thickness: 0.3–10 mm
WT: 1–100 mm
WT: 1–100 mm
Length: 100–12000 mm
Thickness: 3–60 mm
| Item | 304L | 304 | 316L | 321 |
|---|---|---|---|---|
| Carbon level | Low (≤0.03%) | Standard (≤0.08%) | Low (≤0.03%) | Standard (≤0.08%) + Ti stabilized |
| Main strength | Welded fabrication | General use | Chloride resistance | High-temperature stability |
| Marine / chlorides | Needs review | Needs review | Often preferred | Needs review |
| Common uses | Welded tanks, piping | General fabrication | Marine/chemical exposure | High-temperature equipment |
Does 304L require post-weld heat treatment?
Many welded builds use 304L without post-weld annealing, depending on thickness, service environment, and specification. Always align the welding plan with project requirements.
Is 304L suitable for food-contact equipment?
304L is widely used in food processing and commercial kitchens because it is cleanable and resistant to staining in typical service. Confirm finish, cleaning routine, and compliance needs for your market.
How should I specify 304L in an RFQ?
Include the grade and standard (304L / S30403 / SUS304L / 1.4307), product form, size, tolerance, finish, quantity, inspection method, and packing requirements.
Send your grade, size, quantity, finish, and destination. We will reply with a workable offer and lead time.
