Steel A3 · temper · default condition
Steel A3 Annealed
Properties of the Annealed condition, compared with the other A3 tempers.
Standard stock condition for machining the tool before hardening.
What is A3 Annealed?
A3 Annealed is A3 in the Annealed temper — standard stock condition for machining the tool before hardening. A3 Annealed has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 760 MPa (110 ksi) — weaker than 51% of steel grades. Elongation at break is 20% and the elastic modulus is 203 GPa (29.4 Msi). A3 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
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
- Poor heat conductor — 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades
- High embodied carbon — 2.6 kg CO₂/kg, worse than 86% of steel grades
A3 Annealed properties
Typical room-temperature values for A3 Annealed — 12 properties are specific to this condition; the rest are grade-level values shared by every A3 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
A3 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
A3 Annealed has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 760 MPa (110 ksi) — weaker than 51% of steel grades. Elongation at break is 20% and the elastic modulus is 203 GPa (29.4 Msi).
Thermal6
A3 Annealed is rated for continuous service to 200°C (392 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), worse than 90% of steel grades. Thermal expansion is 10.7 µm/m·K (5.94 µin/in·°F).
Electrical3
A3 Annealed conducts electricity at 2.7 % IACS, worse than 96% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (16/100), better than 79% of steel grades.
Sustainability4
Producing a kilogram of A3 Annealed takes about 36 MJ of energy and emits 2.6 kg of CO₂ — more than 88% of steel grades. Typical recycled content is 30%.
Manufacturability8
A3 Annealed's machinability is fair (38/100, worse than 80% of steel grades); weldability poor (15/100); formability poor (20/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other A3 tempers and conditions
A3 is also supplied in 5 other conditions. The full side-by-side table is on the A3 overview.
- AnnealedDefaultStandard stock condition for machining the tool before hardening.430 MPa yield · 19 HRC
- Q&T 60-62 HRCHighest practical wear resistance for A3 — for abrasive blanking, trim edges and gauges with rigid support.2,000 MPa yield · 61 HRC
- Q&T 58-60 HRCGeneral-purpose working hardness for blanking and forming dies — balanced wear and toughness.1,850 MPa yield · 59 HRC
- Q&T 56-58 HRCPick when impact and chipping resistance matter more than maximum wear life.1,700 MPa yield · 57 HRC
Working with A3 Annealed
Is A3 easy to machine?
Machine in the annealed condition with rigid setups, sharp carbide or cobalt HSS tooling and moderate speeds; the high vanadium carbide content accelerates tool and wheel wear, so allow generous grinding stock and finish by grinding after hardening.
Can A3 be welded?
Poor weldability — repair welding only, with 300–450 °C preheat, matching or Cr-Mo tool-steel filler, minimal heat input and an immediate temper at the previous tempering temperature.
Can A3 be formed, bent or molded?
Cold forming is impractical; hot work at 900–1050 °C with slow controlled cooling and full anneal (~845–870 °C, slow cool) afterwards; austenitize 940–970 °C, air quench, temper 175–540 °C — dimensional change on hardening is very small.
What surface finishes work on A3?
Not corrosion resistant: protect with oil, black oxide, phosphating, nitriding or PVD TiN/CrN; polishing is possible but coarse vanadium carbides limit true mirror finish.
A3 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 grade A3 | 1.2 – 1.3 | 1.25 |
| Mn | 0.4 – 0.6 | 0.5 |
| Si | ≤ 0.5 | 0.3 |
| Cr | 4.75 – 5.5 | 5.1 |
| Mo | 0.9 – 1.4 | 1.1 |
| Vhigh V gives extra wear resistance vs A2 | 0.8 – 1.4 | 1 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
A3 Annealed — frequently asked
What is A3 Annealed used for?
A3 Annealed is typically used for blanking and piercing dies, forming and coining punches, trim dies and die inserts, shear and slitter blades, thread-rolling dies and cold-forming tooling. In short: air-hardening cold-work tool.
What is the yield strength of A3 Annealed?
A3 Annealed has a typical yield strength of 430 MPa (62.4 ksi) and a tensile strength of 760 MPa (110 ksi) — weaker than 51% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is A3 Annealed easy to machine?
Not especially — machinability is rated fair (38/100, worse than 80% of steel grades). Machine in the annealed condition with rigid setups, sharp carbide or cobalt HSS tooling and moderate speeds; the high vanadium carbide content accelerates tool and wheel wear, so allow generous grinding stock and finish by grinding after hardening.
Can A3 Annealed be welded?
Not readily — weldability is rated poor (15/100). Poor weldability — repair welding only, with 300–450 °C preheat, matching or Cr-Mo tool-steel filler, minimal heat input and an immediate temper at the previous tempering temperature.
What surface finishes work on A3 Annealed?
Not corrosion resistant: protect with oil, black oxide, phosphating, nitriding or PVD TiN/CrN; polishing is possible but coarse vanadium carbides limit true mirror finish.
Can A3 Annealed be formed, bent or molded?
Cold forming is impractical; hot work at 900–1050 °C with slow controlled cooling and full anneal (~845–870 °C, slow cool) afterwards; austenitize 940–970 °C, air quench, temper 175–540 °C — dimensional change on hardening is very small.
What is the maximum service temperature of A3 Annealed?
A3 Annealed is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in A3 Annealed?
Yes — A3 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 — Standard Specification for Tool Steels Alloy — ASTM International (2022)
- SAE J437/J438 — Tool and Die Steels — SAE International (2015)
- ASM Handbook Vol.1: Properties and Selection: Irons, Steels, and High-Performance Alloys (Tool Steels) — ASM International (1990)
- ASM Specialty Handbook: Tool Materials — ASM International (1995)
- ASM Handbook Vol.16: Machining — ASM International (1989)
- Air-hardening cold work tool steel (A2/A3 class) datasheets — Böhler / Crucible Industries (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.