Steel A6 · temper · default condition
Steel A6 Annealed
Properties of the Annealed condition, compared with the other A6 tempers.
Standard mill/stock condition for bar, plate and flat ground stock; machine to shape here, then harden.
What is A6 Annealed?
A6 Annealed is A6 in the Annealed temper — standard mill/stock condition for bar, plate and flat ground stock; machine to shape here, then harden. A6 Annealed has a yield strength of 415 MPa (60.2 ksi) and a tensile strength of 725 MPa (105 ksi) — weaker than 55% of steel grades. Elongation at break is 22% and the elastic modulus is 203 GPa (29.4 Msi). A6 Annealed has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,425°C (2,597 °F).
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- High embodied carbon — 2.6 kg CO₂/kg, worse than 86% of steel grades
- Poor heat conductor — 27 W/m·K (15.6 BTU/hr·ft·°F), worse than 85% of steel grades
- Difficult to weld — 20/100, worse than 84% of steel grades
A6 Annealed properties
Typical room-temperature values for A6 Annealed — 10 properties are specific to this condition; the rest are grade-level values shared by every A6 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
A6 Annealed has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
A6 Annealed has a yield strength of 415 MPa (60.2 ksi) and a tensile strength of 725 MPa (105 ksi) — weaker than 55% of steel grades. Elongation at break is 22% and the elastic modulus is 203 GPa (29.4 Msi).
Thermal6
A6 Annealed is rated for continuous service to 200°C (392 °F). It conducts heat at 27 W/m·K (15.6 BTU/hr·ft·°F), worse than 85% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical2
A6 Annealed has an electrical resistivity of 6×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of A6 Annealed takes about 34 MJ of energy and emits 2.6 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 45%.
Manufacturability8
A6 Annealed's machinability is fair (50/100, worse than 53% of steel grades); weldability poor (20/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other A6 tempers and conditions
A6 is also supplied in 5 other conditions. The full side-by-side table is on the A6 overview.
- AnnealedDefaultStandard mill/stock condition for bar, plate and flat ground stock; machine to shape here, then harden.415 MPa yield · 235 HB
- Hardened & TemperedStandard working condition for blanking, trimming and forming dies where maximum wear resistance is wanted.1,800 MPa yield · 59 HRC
- Q&THigher tempering temperature (~230–330 °C) trades a few points of hardness for better toughness in shock-loaded dies and punches.1,650 MPa yield · 56 HRC
- H&T 50-54 HRCTemper near 400–480 °C for shear blades, heavy punches and shock tools where chipping is the failure mode.1,500 MPa yield · 52 HRC
Working with A6 Annealed
Is A6 easy to machine?
Machine in the annealed condition with sharp carbide or cobalt HSS tooling and rigid setups; leave 0.1–0.3 mm grinding stock, as hardened A6 needs grinding or EDM only.
Can A6 be welded?
Weldable only for die repair — preheat to 250–300 °C, use matching or tool-steel filler with small stringer beads, and temper immediately after cooling to ~150 °C.
Can A6 be formed, bent or molded?
Cold forming is limited to mild bending of annealed stock; hot work 900–1050 °C, then cool slowly and full anneal at ~745–790 °C with slow furnace cooling.
What surface finishes work on A6?
Harden in air from 845–870 °C (use a neutral atmosphere or foil wrap to prevent decarburization), temper twice, then grind, polish, or apply black oxide, nitriding or PVD for extra wear life.
A6 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 | 0.65 – 0.75 | 0.7 |
| Mnhigh Mn gives deep air hardening from low austenitizing temperature | 1.8 – 2.5 | 2.1 |
| Si | ≤ 0.5 | 0.3 |
| Cr | 0.9 – 1.2 | 1.05 |
| Mo | 0.9 – 1.4 | 1.15 |
| Niresidual | ≤ 0.3 | — |
| Voptional grain refiner | ≤ 0.3 | — |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
A6 Annealed — frequently asked
What is A6 Annealed used for?
A6 Annealed is typically used for cold-work blanking and piercing dies, trim and form die inserts, gauges and master fixtures, punches and stripper plates, shear blades for thin stock and bushings and locating pins. In short: workhorse air-hardening tool.
What is the yield strength of A6 Annealed?
A6 Annealed has a typical yield strength of 415 MPa (60.2 ksi) and a tensile strength of 725 MPa (105 ksi) — weaker than 55% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is A6 Annealed easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine in the annealed condition with sharp carbide or cobalt HSS tooling and rigid setups; leave 0.1–0.3 mm grinding stock, as hardened A6 needs grinding or EDM only.
Can A6 Annealed be welded?
Not readily — weldability is rated poor (20/100). Weldable only for die repair — preheat to 250–300 °C, use matching or tool-steel filler with small stringer beads, and temper immediately after cooling to ~150 °C.
What surface finishes work on A6 Annealed?
Harden in air from 845–870 °C (use a neutral atmosphere or foil wrap to prevent decarburization), temper twice, then grind, polish, or apply black oxide, nitriding or PVD for extra wear life.
Can A6 Annealed be formed, bent or molded?
Cold forming is limited to mild bending of annealed stock; hot work 900–1050 °C, then cool slowly and full anneal at ~745–790 °C with slow furnace cooling.
What is the maximum service temperature of A6 Annealed?
A6 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 A6 Annealed?
Yes — A6 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)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Tool Steels) — ASM International (1990)
- Tool Steels, 5th ed. (Roberts, Krauss, Kennedy) — ASM International (1998)
- A6 air-hardening tool steel datasheet — Crucible / Latrobe / Hudson Tool Steel (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.