Stainless Steel 304N-ANN (Annealed)
Heat-treated state · default condition
AISI/SAE 304N · UNS S30451
Default stock condition for plate, sheet, pipe and bar; maximum ductility, corrosion resistance and weldability with N-boosted yield strength.
Values for the ANN condition
Other 304N tempers and conditions
304N is listed in 8 conditions; see the grade overview at 304N.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefaultThis page Annealed | Default stock condition for plate, sheet, pipe and bar; maximum ductility, corrosion resistance and weldability with N-boosted yield strength. | 320 | 650 | 50 | 180 HB | — |
1/16-Hard | Minimal cold work for extra stiffness and flatness while keeping near-annealed bendability; typical for lightly stressed panels and trim. | 400 | 700 | 42 | 200 HB | — |
1/8-Hard | Modest strength lift with still-good roll forming and moderate bend radii; used for formed structural sections and appliance parts. | 440 | 740 | 37 | 215 HB | — |
Cold drawn | Round/hex bar with improved straightness, surface finish and yield strength for machined shafts and fasteners. | 580 | 790 | 25 | 235 HB | — |
Quarter hard | Common strength/formability compromise for brackets, clamps and light springs where annealed yield is insufficient. | 620 | 930 | 14 | 27 HRC | — |
Half hard | High-strength strip for spring clips, washers and flat springs; only shallow bends across the rolling direction are practical. | 850 | 1,100 | 9 | 33 HRC | — |
Three-quarter hard | Near-maximum cold-worked strength for flat spring stock and shims; essentially non-formable except very gentle radii. | 1,000 | 1,260 | 5 | 37 HRC | — |
Full hard | Maximum as-rolled strength for spring strip, blades and wear shims; brittle in bending and strongly magnetic from deformation martensite. | 1,050 | 1,330 | 4 | 41 HRC | — |
What is 304N-ANN?
304N-ANN is 304N heat treated to ANN — default stock condition for plate, sheet, pipe and bar; maximum ductility, corrosion resistance and weldability with N-boosted yield strength. 304N-ANN has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 650 MPa (94.3 ksi) — weaker than 60% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 193 GPa (28 Msi). 304N-ANN has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Advantages
- Polishes to a fine finish — 85/100, better than 97% of stainless steel grades
- Tough — resists crack growth — 210 MPa·√m (191.1 ksi·√in), better than 95% of stainless steel grades
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
- Forms and bends easily — 78/100, better than 90% of stainless steel grades
- Readily welded — 85/100, better than 87% of stainless steel grades
304N-ANN properties
Typical room-temperature values for 304N-ANN; 19 are specific to this condition. Other listed values are 304N reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
304N-ANN has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
304N-ANN has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 650 MPa (94.3 ksi) — weaker than 60% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
304N-ANN is rated for continuous service to 760°C (1,400 °F). It conducts heat at 16.2 W/m·K (9.36 BTU/hr·ft·°F), better than 64% of stainless steel grades. Thermal expansion is 17.3 µm/m·K (9.61 µin/in·°F).
Electrical3
304N-ANN conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.
Sustainability4
Producing a kilogram of 304N-ANN takes about 55 MJ of energy and emits 5.2 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 65%.
Manufacturability8
304N-ANN's machinability is fair (38/100, better than 63% of stainless steel grades); weldability excellent (85/100); formability very good (78/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 304N-ANN
Is 304N easy to machine?
Gummy and strongly work-hardening — use rigid setups, positive-rake sharp carbide, heavy positive feed to stay under the hardened skin, and flood coolant; expect ~40 % of 1212 speeds.
Can 304N be welded?
Readily welded by GTAW/GMAW/SMAW with 308L or nitrogen-bearing 308LN filler; no preheat, keep interpass below ~150 °C and limit heat input to preserve corrosion resistance.
Can 304N be formed, bent or molded?
Cold formable but with ~25 % higher press loads and more springback than 304; use generous radii, interstage annealing at 1010–1120 °C with rapid cooling for severe draws.
What surface finishes work on 304N?
Not anodizable — passivate per ASTM A967 or electropolish after pickling; takes No.4 brushed and No.8 mirror finishes well, and accepts PVD or chemical colouring.
304N 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 |
|---|---|---|
| CASTM A240 max | ≤ 0.08 | 0.05 |
| Mn | ≤ 2 | 1.6 |
| Si | ≤ 0.75 | 0.5 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.03 | 0.01 |
| Cr | 18 – 20 | 18.5 |
| Ni | 8 – 10.5 | 9 |
| Ndeliberate nitrogen addition — the defining element of 304N | 0.1 – 0.16 | 0.13 |
| Fe | balance | — |
304N-ANN — frequently asked
What is 304N-ANN used for?
304N-ANN is typically used for structural components, pressure vessels and high-strength piping. In short: higher-yield 304; code-friendly pressure vessel grade; same corrosion class as 304.
What is the yield strength of 304N-ANN?
304N-ANN has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 650 MPa (94.3 ksi) — weaker than 60% of stainless steel grades. Strength varies by condition: see the 8 listed tempers.
Is 304N-ANN easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Gummy and strongly work-hardening — use rigid setups, positive-rake sharp carbide, heavy positive feed to stay under the hardened skin, and flood coolant; expect ~40 % of 1212 speeds.
Can 304N-ANN be welded?
Yes — weldability is rated excellent (85/100). Readily welded by GTAW/GMAW/SMAW with 308L or nitrogen-bearing 308LN filler; no preheat, keep interpass below ~150 °C and limit heat input to preserve corrosion resistance.
What surface finishes work on 304N-ANN?
Not anodizable — passivate per ASTM A967 or electropolish after pickling; takes No.4 brushed and No.8 mirror finishes well, and accepts PVD or chemical colouring.
Can 304N-ANN be formed, bent or molded?
Cold formable but with ~25 % higher press loads and more springback than 304; use generous radii, interstage annealing at 1010–1120 °C with rapid cooling for severe draws.
What is the maximum service temperature of 304N-ANN?
304N-ANN is rated for continuous use to about 760°C (1,400 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 304N-ANN and 304N-FH?
ANN is the default condition — default stock condition for plate, sheet, pipe and bar; maximum ductility, corrosion resistance and weldability with N-boosted yield strength. FH: maximum as-rolled strength for spring strip, blades and wear shims; brittle in bending and strongly magnetic from deformation martensite. Yield strength is 320 MPa in ANN versus 1,050 MPa in FH.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip — ASTM International (2023)
- ASTM A666 — Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate and Flat Bar — ASTM International (2015)
- ASTM A276/A276M — Stainless Steel Bars and Shapes — ASTM International (2023)
- ASME BPVC Section II Part D — Materials, Properties — ASME (2023)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Outokumpu Steel Grades, Properties and Global Standards — Outokumpu (2022)
- GB/T 4237 / GB/T 20878 06Cr19Ni10N (304N) (2015)
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.