Stainless Steel 304 · supply condition
Stainless Steel 304-1/2 Hard
Properties of the 1/2 Hard condition, compared with the other 304 tempers.
For springy, high-strength flat parts and structural strip where only simple large-radius bends are required.
What is 304-1/2 Hard?
304-1/2 Hard is 304 supplied in the 1/2 Hard condition — for springy, high-strength flat parts and structural strip where only simple large-radius bends are required. 304-1/2 Hard has a yield strength of 820 MPa (119 ksi) and a tensile strength of 1,070 MPa (155 ksi) — stronger than 97% of stainless steel grades. Elongation at break is 10% and the elastic modulus is 193 GPa (28 Msi). 304-1/2 Hard has a density of 7.95 g/cm³ (0.287 lb/in³), heavier than 81% of stainless steel grades. It melts at 1,400°C (2,552 °F). Annealed is the default condition FabDigit quotes; 1/2 Hard is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 88/100, better than 100% of stainless steel grades
- High strength — 820 MPa (119 ksi), better than 97% of stainless steel grades
- Tough — resists crack growth — 220 MPa·√m (200.2 ksi·√in), better than 97% of stainless steel grades
- Easy to machine — 50/100, better than 90% of stainless steel grades
Limitations
- Limited ductility — 10%, worse than 98% of stainless steel grades
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
304-1/2 Hard properties
Typical room-temperature values for 304-1/2 Hard — 28 properties are specific to this condition; the rest are grade-level values shared by every 304 temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
304-1/2 Hard has a density of 7.95 g/cm³ (0.287 lb/in³), heavier than 81% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
304-1/2 Hard has a yield strength of 820 MPa (119 ksi) and a tensile strength of 1,070 MPa (155 ksi) — stronger than 97% of stainless steel grades. Elongation at break is 10% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
304-1/2 Hard is rated for continuous service to 300°C (572 °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
304-1/2 Hard 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 304-1/2 Hard takes about 53 MJ of energy and emits 5.4 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 70%.
Manufacturability7
304-1/2 Hard's machinability is fair (50/100, better than 90% of stainless steel grades); weldability very good (70/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 304 tempers and conditions
304 is also supplied in 10 other conditions. The full side-by-side table is on the 304 overview.
- AnnealedDefaultDefault stock condition for sheet, plate, tube and bar; maximum formability, corrosion resistance and non-magnetic behaviour.250 MPa yield · 150 HB
- Full HardMaximum-strength cold-rolled strip for springs, blades, gaskets and shims; forming limited to very light bends.1,050 MPa yield · 41 HRC
- 3/4 HardHigh-strength strip for flat springs, shims and wear strips with minimal forming.1,000 MPa yield · 37 HRC
- 1/2 HardFor springy, high-strength flat parts and structural strip where only simple large-radius bends are required.820 MPa yield · 32 HRC
- 1/4 HardPick when moderate strength increase is needed while retaining some bendability (structural trim, brackets, clamps).620 MPa yield · 25 HRC
- Cold DrawnStandard condition for round/hex bar and screw-machine stock: higher strength, tighter tolerance and better chip control than annealed bar.550 MPa yield · 20 HRC
- 1/8 HardCold-rolled 304 strip/sheet temper per ASTM A666 between 1/16 and 1/4 hard — moderate strength with useful bend formability.480 MPa yield · 21 HRC
- 1/16 HardLightly cold-rolled 304 temper per ASTM A666 — modest strength gain with most of the annealed ductility and formability retained.380 MPa yield · 190 HB
- Cold RolledChoose for flat, bright, dimensionally accurate sheet with modestly raised strength and a good surface for polishing.330 MPa yield · 180 HB
Working with 304-1/2 Hard
Is 304 easy to machine?
Work-hardens rapidly — use rigid setups, sharp positive-rake carbide, heavy constant feed, low-to-moderate speed (~80–120 m/min) and copious coolant; avoid dwelling or rubbing (consider 303 for high-volume turning).
Can 304 be welded?
Excellent weldability by GTAW/GMAW/resistance/laser using 308L or 316L filler; keep interpass temperature low and heat input modest, no preheat, and use 304L or post-weld solution anneal on thick sections to avoid sensitisation.
Can 304 be formed, bent or molded?
Outstanding cold formability (deep drawing, roll forming, spinning) thanks to high n-value; allow for high springback and ~2× the press force of mild steel, and interstage anneal for severe multi-draw parts.
What surface finishes work on 304?
Not anodisable — finish by pickling/passivation (ASTM A967), electropolishing, bead blasting, brushed No.4 or mirror No.8 polishing; PVD colour coating and electro-colouring are also common.
304 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 |
|---|---|---|
| C≤0.030 for the 304L / 1.4307 variant | ≤ 0.08 | 0.05 |
| Mn | ≤ 2 | 1.5 |
| Si≤1.00 in EN 1.4301 | ≤ 0.75 | 0.5 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.03 | 0.01 |
| Cr | 18 – 20 | 18.5 |
| Ni | 8 – 10.5 | 8.5 |
| N | ≤ 0.1 | 0.05 |
| Fe | balance | — |
304-1/2 Hard — frequently asked
What is 304-1/2 Hard used for?
304-1/2 Hard is typically used for food processing equipment, kitchen appliances and sinks, sanitary tanks and process piping, architectural trim and cladding, heat exchanger and instrument tubing and enclosures and formed sheet metal parts. In short: most common stainless steel.
What is the yield strength of 304-1/2 Hard?
304-1/2 Hard has a typical yield strength of 820 MPa (119 ksi) and a tensile strength of 1,070 MPa (155 ksi) — stronger than 97% of stainless steel grades. Strength varies by condition: see the 11 listed tempers.
Is 304-1/2 Hard easy to machine?
Reasonably — machinability is rated fair (50/100, better than 90% of stainless steel grades). Work-hardens rapidly — use rigid setups, sharp positive-rake carbide, heavy constant feed, low-to-moderate speed (~80–120 m/min) and copious coolant; avoid dwelling or rubbing (consider 303 for high-volume turning).
Can 304-1/2 Hard be welded?
Yes — weldability is rated very good (70/100). Excellent weldability by GTAW/GMAW/resistance/laser using 308L or 316L filler; keep interpass temperature low and heat input modest, no preheat, and use 304L or post-weld solution anneal on thick sections to avoid sensitisation.
What surface finishes work on 304-1/2 Hard?
Not anodisable — finish by pickling/passivation (ASTM A967), electropolishing, bead blasting, brushed No.4 or mirror No.8 polishing; PVD colour coating and electro-colouring are also common.
Can 304-1/2 Hard be formed, bent or molded?
Outstanding cold formability (deep drawing, roll forming, spinning) thanks to high n-value; allow for high springback and ~2× the press force of mild steel, and interstage anneal for severe multi-draw parts.
What is the maximum service temperature of 304-1/2 Hard?
304-1/2 Hard is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 304 Annealed and 304 A2-70?
Annealed is the default condition — default stock condition for sheet, plate, tube and bar; maximum formability, corrosion resistance and non-magnetic behaviour. A2-70: specify for stainless bolts, screws and studs: cold-worked 304 wire meeting ISO 3506 class A2-70 strength minima. Yield strength is 250 MPa in Annealed versus 500 MPa in A2-70.
Can FabDigit make parts in 304-1/2 Hard?
Yes — 304-1/2 Hard is available for CNC machining, sheet metal and casting & forging 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 A666 — Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate and Flat Bar — ASTM International (2015)
- ASTM A276/A479 — Stainless Steel Bars and Shapes — ASTM International (2022)
- EN 10088-1/-2 — Stainless steels: list of grades and technical delivery conditions — CEN (2014)
- JIS G4305 — Cold-rolled stainless steel plate, sheet and strip (SUS304) — JISC (2021)
- ISO 3506-1 — Fasteners, corrosion-resistant stainless steel (A2-70) — ISO (2020)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Outokumpu Core 304/4301 datasheet & Corrosion Handbook — Outokumpu (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.