Stainless Steel 304LN · heat-treated state · default condition
Stainless Steel 304LN Solution Annealed
Properties of the Solution Annealed condition, compared with the other 304LN tempers.
Default condition for pressure-vessel plate, pipe and forgings — maximum corrosion resistance and toughness with code-allowable N-strengthened yield.
What is 304LN Solution Annealed?
304LN Solution Annealed is 304LN heat treated to Solution Annealed — default condition for pressure-vessel plate, pipe and forgings — maximum corrosion resistance and toughness with code-allowable N-strengthened yield. 304LN Solution Annealed has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 196 GPa (28.4 Msi). 304LN Solution Annealed has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 67% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Advantages
- Readily welded — 88/100, better than 91% of stainless steel grades
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
- Forms and bends easily — 75/100, better than 87% of stainless steel grades
- Tough — resists crack growth — 200 MPa·√m (182 ksi·√in), better than 84% of stainless steel grades
Limitations
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
304LN Solution Annealed properties
Typical room-temperature values for 304LN Solution Annealed — 14 properties are specific to this condition; the rest are grade-level values shared by every 304LN temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
304LN Solution Annealed has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 67% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
304LN Solution Annealed has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
304LN Solution Annealed is rated for continuous service to 400°C (752 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 16 µm/m·K (8.89 µin/in·°F).
Electrical3
304LN Solution Annealed conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 55% of stainless steel grades.
Sustainability4
Producing a kilogram of 304LN Solution Annealed takes about 55 MJ of energy and emits 5 kg of CO₂ — less than 51% of stainless steel grades. Typical recycled content is 70%.
Manufacturability7
304LN Solution Annealed's machinability is fair (38/100, better than 63% of stainless steel grades); weldability excellent (88/100); formability very good (75/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 304LN tempers and conditions
304LN is also supplied in 9 other conditions. The full side-by-side table is on the 304LN overview.
- Solution AnnealedDefaultDefault condition for pressure-vessel plate, pipe and forgings — maximum corrosion resistance and toughness with code-allowable N-strengthened yield.330 MPa yield · 170 HB
- FHMaximum cold-worked strength for flat springs, shims and wear strip; essentially no formability.1,000 MPa yield · 40 HRC
- 1/2HHigh-strength strip for clamps, straps and lightly bent structural parts; limited ductility.790 MPa yield · 32 HRC
- CDPick for bar and tube needing tighter tolerance, better surface and ~40 % higher proof strength than annealed.550 MPa yield · 22 HRC
- 1/4HUse for lightly formed springy sheet parts and structural strip needing ~500 MPa proof strength.550 MPa yield · 25 HRC
- 1/8HLightly cold-rolled 304LN strip one step above 1/16 hard — modestly higher yield strength and springback with still-good bending and drawing behaviour.450 MPa yield · 210 HB
- 1/16HLightly temper-rolled 304LN sheet/strip (ASTM A666 class) — small strength gain over annealed while keeping near-full ductility and formability.380 MPa yield · 190 HB
- AnnealedStandard soft sheet/strip condition for forming, deep drawing and welded fabrication.320 MPa yield · 165 HB
Working with 304LN Solution Annealed
Is 304LN easy to machine?
Work-hardens fast and is slightly harder to cut than 304L because of the nitrogen — use rigid setups, sharp coated carbide, positive rake, heavy constant feed, no dwelling, and flood coolant.
Can 304LN be welded?
Excellent with GTAW/GMAW/SMAW using 308L/308LSi (or 316L) filler; low carbon means no post-weld anneal, but keep heat input moderate and interpass low to limit distortion and δ-ferrite loss.
Can 304LN be formed, bent or molded?
Very good deep-draw and bend behaviour in the annealed condition, though springback and press loads are higher than 304L; anneal 1020–1080 °C + rapid cool to restore ductility after heavy cold work.
What surface finishes work on 304LN?
Not anodised — passivate per ASTM A967 or electropolish after pickling; takes bright 2B/BA/No.4/No.8 mill and mechanical finishes well.
304LN chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Clow-carbon to avoid weld sensitisation | ≤ 0.03 | 0.02 |
| Si≤1.00 in EN 10088-2 | ≤ 0.75 | 0.5 |
| Mn | ≤ 2 | 1.5 |
| P | ≤ 0.05 | 0.03 |
| S≤0.015 in EN 10088-2 | ≤ 0.03 | 0.01 |
| CrEN 1.4311: 17.5–19.5 | 18 – 20 | 18.5 |
| NiEN 1.4311: 8.5–11.5 | 8 – 12 | 9.5 |
| Nstrengthening addition; EN 1.4311: 0.12–0.22 | 0.1 – 0.16 | 0.14 |
| Fe | balance | — |
304LN Solution Annealed — frequently asked
What is 304LN Solution Annealed used for?
304LN Solution Annealed is typically used for welded cryogenic vessels, LNG pipework, liquid nitrogen and oxygen storage tanks, cryogenic valve bodies, chemical process piping and welded structural stainless frames. In short: low-carbon nitrogen 304.
What is the yield strength of 304LN Solution Annealed?
304LN Solution Annealed has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 57% of stainless steel grades. Strength varies by condition: see the 10 listed tempers.
Is 304LN Solution Annealed easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Work-hardens fast and is slightly harder to cut than 304L because of the nitrogen — use rigid setups, sharp coated carbide, positive rake, heavy constant feed, no dwelling, and flood coolant.
Can 304LN Solution Annealed be welded?
Yes — weldability is rated excellent (88/100). Excellent with GTAW/GMAW/SMAW using 308L/308LSi (or 316L) filler; low carbon means no post-weld anneal, but keep heat input moderate and interpass low to limit distortion and δ-ferrite loss.
What surface finishes work on 304LN Solution Annealed?
Not anodised — passivate per ASTM A967 or electropolish after pickling; takes bright 2B/BA/No.4/No.8 mill and mechanical finishes well.
Can 304LN Solution Annealed be formed, bent or molded?
Very good deep-draw and bend behaviour in the annealed condition, though springback and press loads are higher than 304L; anneal 1020–1080 °C + rapid cool to restore ductility after heavy cold work.
What is the maximum service temperature of 304LN Solution Annealed?
304LN Solution Annealed is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 304LN Solution Annealed and 304LN-FH?
Solution Annealed is the default condition — default condition for pressure-vessel plate, pipe and forgings — maximum corrosion resistance and toughness with code-allowable N-strengthened yield. FH: maximum cold-worked strength for flat springs, shims and wear strip; essentially no formability. Yield strength is 330 MPa in Solution Annealed versus 1,000 MPa in FH.
Can FabDigit make parts in 304LN Solution Annealed?
Yes — 304LN Solution Annealed is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A240/A240M (S30453 plate, sheet, strip) — ASTM International (2023)
- ASTM A312/A312M & A213 (TP304LN pipe/tube) — ASTM International (2022)
- ASTM A666 (cold-worked austenitic sheet/strip tempers) — ASTM International (2015)
- EN 10088-1 / EN 10088-2 (X2CrNiN18-10, 1.4311) — CEN (2014)
- GB/T 24511 / GB/T 1220 (022Cr19Ni10N) — SAC (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
- Outokumpu Steel Grades / Supra 304L-4311 data — Outokumpu (2023)
- ASME BPVC Section II Part D allowable stresses, S30453 — ASME (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.