Stainless Steel 304 A2-70
Certified grade
AISI/SAE 304 · UNS S30400 · EN 1.4301, X5CrNi18-10 · JIS SUS304 · GB 06Cr19Ni10, 0Cr18Ni9
A2-70 = cold-worked fastener property class
Specify for stainless bolts, screws and studs: cold-worked 304 wire meeting ISO 3506 class A2-70 strength minima.
Values for the A2-70 condition
Other 304 tempers and conditions
304 is listed in 11 conditions; see the grade overview at 304.
Compare all 11 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault solution annealed (2B / No.1 / 2D mill condition) | Default stock condition for sheet, plate, tube and bar; maximum formability, corrosion resistance and non-magnetic behaviour. | 250 | 585 | 55 | 150 HB | — |
cold-rolled and skin-passed strip/sheet (light temper) | Choose for flat, bright, dimensionally accurate sheet with modestly raised strength and a good surface for polishing. | 330 | 640 | 45 | 180 HB | — |
Cold Work | Lightly cold-rolled 304 temper per ASTM A666 — modest strength gain with most of the annealed ductility and formability retained. | 380 | 655 | 35 | 190 HB | 2.4 % IACS |
Cold Work | Cold-rolled 304 strip/sheet temper per ASTM A666 between 1/16 and 1/4 hard — moderate strength with useful bend formability. | 480 | 725 | 25 | 21 HRC | 2.4 % IACS |
A2-70This page Cold-worked fastener property class | Specify for stainless bolts, screws and studs: cold-worked 304 wire meeting ISO 3506 class A2-70 strength minima. | 500 | 750 | 20 | 22 HRC | 2.4 % IACS |
cold-drawn bar / wire (ASTM A484, A276) | Standard condition for round/hex bar and screw-machine stock: higher strength, tighter tolerance and better chip control than annealed bar. | 550 | 760 | 30 | 20 HRC | — |
Quarter hard | Pick when moderate strength increase is needed while retaining some bendability (structural trim, brackets, clamps). | 620 | 900 | 15 | 25 HRC | 16 W/m·K |
Half hard | For springy, high-strength flat parts and structural strip where only simple large-radius bends are required. | 820 | 1,070 | 10 | 32 HRC | 16 W/m·K |
Three-quarter hard | High-strength strip for flat springs, shims and wear strips with minimal forming. | 1,000 | 1,270 | 6 | 37 HRC | 2.3 % IACS |
cold worked temper per ASTM A666 | Maximum-strength cold-rolled strip for springs, blades, gaskets and shims; forming limited to very light bends. | 1,050 | 1,350 | 4 | 41 HRC | 2.3 % IACS |
heavily cold-drawn wire (ASTM A313) | Fine cold-drawn 304 wire for compression/extension springs and woven mesh where very high tensile strength is required. | 1,500 | 1,750 | 3 | 46 HRC | 2.4 % IACS |
What is 304 A2-70?
304 A2-70 is 304 in a A2-70 certified grade — specify for stainless bolts, screws and studs: cold-worked 304 wire meeting ISO 3506 class A2-70 strength minima. 304 A2-70 has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 77% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 193 GPa (28 Msi). 304 A2-70 has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,400°C (2,552 °F). Annealed is the default condition FabDigit quotes; A2-70 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 — 500 MPa (72.5 ksi), better than 77% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Limited ductility — 20%, worse than 79% of stainless steel grades
304 A2-70 properties
Typical room-temperature values for 304 A2-70; 24 are specific to this condition. Other listed values are 304 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
304 A2-70 has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
304 A2-70 has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 77% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
304 A2-70 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 A2-70 conducts electricity at 2.4 % IACS, better than 67% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 68% of stainless steel grades.
Sustainability4
Producing a kilogram of 304 A2-70 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 A2-70's machinability is fair (40/100, better than 72% of stainless steel grades); weldability very good (75/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 304 A2-70
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 A2-70 — frequently asked
What is 304 A2-70 used for?
304 A2-70 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 A2-70?
304 A2-70 has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 77% of stainless steel grades. Strength varies by condition: see the 11 listed tempers.
Is 304 A2-70 easy to machine?
Not especially — machinability is rated fair (40/100, better than 72% 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 A2-70 be welded?
Yes — weldability is rated very good (75/100). 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 A2-70?
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 A2-70 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 A2-70?
304 A2-70 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 A2-70?
Yes — 304 A2-70 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.