Steel A2 · temper · default condition
Steel A2 Annealed
Properties of the Annealed condition, compared with the other A2 tempers.
Standard as-supplied condition for machining dies and punches before hardening; also the form of ground flat stock.
What is A2 Annealed?
A2 Annealed is A2 in the Annealed temper — standard as-supplied condition for machining dies and punches before hardening; also the form of ground flat stock. A2 Annealed has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 740 MPa (107 ksi) — stronger than 58% of steel grades. Elongation at break is 22% and the elastic modulus is 203 GPa (29.4 Msi). A2 Annealed has a density of 7.86 g/cm³ (0.284 lb/in³), heavier than 89% of steel grades. It melts at 1,420°C (2,588 °F).
Advantages
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- Low electrical conductivity — 2.7 % IACS, worse than 96% of steel grades
- Poor heat conductor — 26 W/m·K (15 BTU/hr·ft·°F), worse than 86% of steel grades
- High embodied carbon — 2.6 kg CO₂/kg, worse than 86% of steel grades
- Difficult to weld — 20/100, worse than 84% of steel grades
A2 Annealed properties
Typical room-temperature values for A2 Annealed — 11 properties are specific to this condition; the rest are grade-level values shared by every A2 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
A2 Annealed has a density of 7.86 g/cm³ (0.284 lb/in³), heavier than 89% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical15
A2 Annealed has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 740 MPa (107 ksi) — stronger than 58% of steel grades. Elongation at break is 22% and the elastic modulus is 203 GPa (29.4 Msi).
Thermal6
A2 Annealed is rated for continuous service to 425°C (797 °F). It conducts heat at 26 W/m·K (15 BTU/hr·ft·°F), worse than 86% of steel grades. Thermal expansion is 10.7 µm/m·K (5.94 µin/in·°F).
Electrical3
A2 Annealed conducts electricity at 2.7 % IACS, worse than 96% of steel grades.
Chemical & Environmental2
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of A2 Annealed takes about 36 MJ of energy and emits 2.6 kg of CO₂ — more than 88% of steel grades. Typical recycled content is 35%.
Manufacturability8
A2 Annealed's machinability is fair (45/100, worse than 65% of steel grades); weldability poor (20/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other A2 tempers and conditions
A2 is also supplied in 6 other conditions. The full side-by-side table is on the A2 overview.
- AnnealedDefaultStandard as-supplied condition for machining dies and punches before hardening; also the form of ground flat stock.470 MPa yield · 217 HB
- Hardened & TemperedGeneral working condition for blanking dies, punches and shear blades needing maximum wear resistance.1,900 MPa yield · 60 HRC
- Q&TOrder this when the supplier heat treats to a customer-specified hardness band rather than the maximum.1,800 MPa yield · 58 HRC
- HT 54-56 HRCChoose for heavy shear blades, cold forming and trimming tools where chipping is the failure mode.1,650 MPa yield · 55 HRC
Working with A2 Annealed
Is A2 easy to machine?
Machine in the annealed condition with carbide or cobalt HSS at moderate speeds; leave 0.2–0.5 mm grinding stock, stress-relieve rough-machined dies at 650–700 °C, and finish hardened parts by grinding, EDM or hard turning.
Can A2 be welded?
Poor weldability — for repair only: preheat to 400–500 °C, use matched 5 %Cr filler, weld hot and temper immediately at the original tempering temperature to avoid cracking.
Can A2 be formed, bent or molded?
Cold forming is impractical; hot work at 900–1050 °C with slow cooling, then full anneal at 845–870 °C (furnace cool 10–20 °C/h) before machining. Hardening: austenitise 940–980 °C, air (or plate/vacuum) quench, temper twice.
What surface finishes work on A2?
Takes a fine mirror polish when hardened; protect with oil, black oxide, or apply nitriding, hard chrome or TiN/CrN/TiCN PVD (below tempering temperature) to boost wear and galling resistance.
A2 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 A681 A2 | 0.95 – 1.05 | 1 |
| Mn | 0.4 – 1 | 0.7 |
| Si | 0.1 – 0.5 | 0.3 |
| Cr | 4.75 – 5.5 | 5.1 |
| Mo | 0.9 – 1.4 | 1.1 |
| V | 0.15 – 0.5 | 0.25 |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.25 | — |
| Wresidual | ≤ 0.3 | — |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
A2 Annealed — frequently asked
What is A2 Annealed used for?
A2 Annealed is typically used for blanking dies, forming punches, shear and trim blades, cold-work die inserts, gauges and checking fixtures and precision-ground flat stock details. In short: versatile air-hardening tool.
What is the yield strength of A2 Annealed?
A2 Annealed has a typical yield strength of 470 MPa (68.2 ksi) and a tensile strength of 740 MPa (107 ksi) — stronger than 58% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is A2 Annealed easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine in the annealed condition with carbide or cobalt HSS at moderate speeds; leave 0.2–0.5 mm grinding stock, stress-relieve rough-machined dies at 650–700 °C, and finish hardened parts by grinding, EDM or hard turning.
Can A2 Annealed be welded?
Not readily — weldability is rated poor (20/100). Poor weldability — for repair only: preheat to 400–500 °C, use matched 5 %Cr filler, weld hot and temper immediately at the original tempering temperature to avoid cracking.
What surface finishes work on A2 Annealed?
Takes a fine mirror polish when hardened; protect with oil, black oxide, or apply nitriding, hard chrome or TiN/CrN/TiCN PVD (below tempering temperature) to boost wear and galling resistance.
Can A2 Annealed be formed, bent or molded?
Cold forming is impractical; hot work at 900–1050 °C with slow cooling, then full anneal at 845–870 °C (furnace cool 10–20 °C/h) before machining. Hardening: austenitise 940–980 °C, air (or plate/vacuum) quench, temper twice.
What is the maximum service temperature of A2 Annealed?
A2 Annealed is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in A2 Annealed?
Yes — A2 Annealed is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A681 — Alloy Tool Steels — ASTM International (2015)
- DIN EN ISO 4957 — Tool steels (X100CrMoV5, 1.2363) — DIN/ISO (2018)
- JIS G4404 — Alloy tool steels (SKD12) — JSA (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Tool Steels, 5th ed. — ASM International (1998)
- Cold work tool steel 1.2363 / A2 datasheet — Böhler / voestalpine (2020)
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.