Stainless Steel 304H · temper
Stainless Steel 304H Annealed
Properties of the Annealed condition, compared with the other 304H tempers.
General mill-annealed condition for sheet, strip and bar where the ASME coarse-grain solution treatment is not separately certified.
What is 304H Annealed?
304H Annealed is 304H in the Annealed temper — general mill-annealed condition for sheet, strip and bar where the ASME coarse-grain solution treatment is not separately certified. 304H Annealed has a yield strength of 265 MPa (38.4 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 80% of stainless steel grades. Elongation at break is 53% and the elastic modulus is 193 GPa (28 Msi). 304H 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). Solution Annealed is the default condition FabDigit quotes; Annealed is available on request or by drawing note.
Advantages
- Forms and bends easily — 90/100, better than 98% of stainless steel grades
- Tough — resists crack growth — 220 MPa·√m (200.2 ksi·√in), better than 97% of stainless steel grades
- Ductile — tolerates forming and impact — 53%, better than 95% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
- Readily welded — 85/100, better than 86% of stainless steel grades
Limitations
- Low strength — 265 MPa (38.4 ksi), worse than 80% of stainless steel grades
304H Annealed properties
Typical room-temperature values for 304H Annealed — 8 properties are specific to this condition; the rest are grade-level values shared by every 304H temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
304H 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
304H Annealed has a yield strength of 265 MPa (38.4 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 80% of stainless steel grades. Elongation at break is 53% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
304H Annealed is rated for continuous service to 815°C (1,499 °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
304H Annealed conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 53% of stainless steel grades.
Sustainability4
Producing a kilogram of 304H Annealed takes about 53 MJ of energy and emits 4.5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 65%.
Manufacturability8
304H Annealed's machinability is fair (40/100, better than 73% of stainless steel grades); weldability excellent (85/100); formability excellent (90/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 304H tempers and conditions
304H is also supplied in 5 other conditions. The full side-by-side table is on the 304H overview.
- Solution AnnealedDefaultStandard supply condition for plate, tube and forgings used in ASME high-temperature service; maximum ductility and carbide dissolution.260 MPa yield · 150 HB
- Cold DrawnChoose for straight, close-tolerance bar or tube where higher yield strength and better surface finish are needed below the sensitization range.450 MPa yield · 210 HB
- AnnealedGeneral mill-annealed condition for sheet, strip and bar where the ASME coarse-grain solution treatment is not separately certified.265 MPa yield · 155 HB
Working with 304H Annealed
Is 304H easy to machine?
Gummy and work-hardening like 304 — use rigid setups, positive-rake sharp carbide, heavy constant feed and flood coolant; ~45 % of AISI 1212.
Can 304H be welded?
Readily welded by GTAW/GMAW/SMAW with 308H filler to match creep strength; no preheat, keep interpass low, and remember the high carbon means sensitization risk if slow-cooled through 425–870 °C.
Can 304H be formed, bent or molded?
Excellent cold formability (deep drawing, roll forming, bending), but high work-hardening rate demands more power and generous bend radii; hot work at 1150–1200 °C then solution anneal.
What surface finishes work on 304H?
Not anodizable; passivate per ASTM A967, or pickle/electropolish welds — mechanical polishing to No.4/No.8 is straightforward.
304H 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 |
|---|---|---|
| Craised carbon is the defining feature of the H grade | 0.04 – 0.1 | 0.06 |
| Mn | ≤ 2 | 1.5 |
| 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 |
| N | ≤ 0.1 | 0.05 |
| Fe | balance | — |
304H Annealed — frequently asked
What is 304H Annealed used for?
304H Annealed is typically used for pressure vessels, welded boiler tubes, superheater and reheater components, high-temperature process piping and flanges, heat exchanger shells and furnace hardware and supports. In short: high-temp 304 plate.
What is the yield strength of 304H Annealed?
304H Annealed has a typical yield strength of 265 MPa (38.4 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 80% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 304H Annealed easy to machine?
Not especially — machinability is rated fair (40/100, better than 73% of stainless steel grades). Gummy and work-hardening like 304 — use rigid setups, positive-rake sharp carbide, heavy constant feed and flood coolant; ~45 % of AISI 1212.
Can 304H Annealed be welded?
Yes — weldability is rated excellent (85/100). Readily welded by GTAW/GMAW/SMAW with 308H filler to match creep strength; no preheat, keep interpass low, and remember the high carbon means sensitization risk if slow-cooled through 425–870 °C.
What surface finishes work on 304H Annealed?
Not anodizable; passivate per ASTM A967, or pickle/electropolish welds — mechanical polishing to No.4/No.8 is straightforward.
Can 304H Annealed be formed, bent or molded?
Excellent cold formability (deep drawing, roll forming, bending), but high work-hardening rate demands more power and generous bend radii; hot work at 1150–1200 °C then solution anneal.
What is the maximum service temperature of 304H Annealed?
304H Annealed is rated for continuous use to about 815°C (1,499 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 304H Solution Annealed and 304H HRAP?
Solution Annealed is the default condition — standard supply condition for plate, tube and forgings used in ASME high-temperature service; maximum ductility and carbide dissolution. HRAP: standard heavy plate condition (>4 mm) for pressure vessels and furnace parts; matte pickled 1D surface. Yield strength is 260 MPa in Solution Annealed versus 255 MPa in HRAP.
Can FabDigit make parts in 304H Annealed?
Yes — 304H 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 — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip — ASTM International (2023)
- ASTM A213/A213M — Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater and Heat-Exchanger Tubes — ASTM International (2022)
- ASTM A182/A182M — Forged or Rolled Alloy and Stainless Steel Pipe Flanges and Fittings — ASTM International (2022)
- ASME BPVC Section II Part D — Materials, Properties — ASME (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Outokumpu Corrosion Handbook / Stainless Steel Datasheets — Outokumpu (2021)
- EN 10028-7 (1.4948 X6CrNi18-10) — CEN (2016)
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.