Steel H26-ANN (Annealed)
Heat-treated state · default condition
AISI/SAE H26 · UNS T20826
Standard mill supply condition for bar and forgings; machine tooling here, then harden and temper.
Values for the ANN condition
Other H26 tempers and conditions
H26 is listed in 5 conditions; see the grade overview at H26.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefaultThis page Annealed | Standard mill supply condition for bar and forgings; machine tooling here, then harden and temper. | 560 | 850 | 18 | 229 HB | 26 W/m·K |
Stress relieved | Intermediate step after heavy rough machining of large dies to minimise distortion during hardening. | 575 | 860 | 17 | 235 HB | 3.1 % IACS |
Hot rolled | As-forged or hot-rolled stock supplied for further hot work or full anneal before machining; not a service condition. | 760 | 1,100 | 8 | 35 HRC | 3.1 % IACS |
Hardened & tempered 58–60 HRC | Toughness-biased working hardness for hot extrusion dies and punches where thermal shock and cracking risk dominate. | — | 2,000 | 2 | 59 HRC | 25 W/m·K |
Hardened & tempered 60–63 HRC | Maximum hot hardness and wear resistance for hot punches, mandrels and hot-shear blades in low-impact service. | — | 2,150 | 1 | 62 HRC | — |
What is H26-ANN?
H26-ANN is H26 heat treated to ANN — standard mill supply condition for bar and forgings; machine tooling here, then harden and temper. H26-ANN has a yield strength of 560 MPa (81.2 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 73% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi). H26-ANN has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 100% of steel grades. It melts at 1,400°C (2,552 °F).
Limitations
- Heavy — 8.89 g/cm³ (0.321 lb/in³), worse than 100% of steel grades
- High embodied carbon — 3.6 kg CO₂/kg, worse than 94% of steel grades
- Low electrical conductivity — 3.1 % IACS, worse than 89% of steel grades
- Poor heat conductor — 26 W/m·K (15 BTU/hr·ft·°F), worse than 87% of steel grades
- Difficult to machine — 32/100, worse than 87% of steel grades
H26-ANN properties
Typical room-temperature values for H26-ANN; 13 are specific to this condition. Other listed values are H26 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
H26-ANN has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 100% of steel grades. It melts at 1,400°C (2,552 °F).
Mechanical14
H26-ANN has a yield strength of 560 MPa (81.2 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 73% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
H26-ANN is rated for continuous service to 400°C (752 °F). It conducts heat at 26 W/m·K (15 BTU/hr·ft·°F), worse than 87% of steel grades. Thermal expansion is 11.2 µm/m·K (6.22 µin/in·°F).
Electrical3
H26-ANN conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental2
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of H26-ANN takes about 48 MJ of energy and emits 3.6 kg of CO₂ — more than 93% of steel grades. Typical recycled content is 45%.
Manufacturability8
H26-ANN's machinability is poor (32/100, worse than 87% of steel grades); weldability poor (20/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with H26-ANN
Is H26 easy to machine?
Machine only in the annealed condition with rigid setups, low speeds and carbide or cobalt HSS tooling; the ~18% W and vanadium carbides are abrasive, so finish-grind with soft, friable alumina or CBN wheels after hardening.
Can H26 be welded?
Fusion welding is limited to die repair — preheat to 400–500 °C, use matched or high-alloy filler, weld hot and immediately temper below the last tempering temperature to avoid cracking.
Can H26 be formed, bent or molded?
Cold forming is not practical; hot work between 1050 and 1150 °C, never below ~950 °C, and slow-cool/anneal at 870–900 °C after forging.
What surface finishes work on H26?
Salt-bath or gas nitriding and PVD TiAlN/CrN coatings are common for extrusion tooling; oil or phosphate protection is needed for storage since corrosion resistance is low.
H26 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 |
|---|---|---|
| Chigher C than H21/H25 for wear resistance | 0.45 – 0.55 | 0.5 |
| Mn | 0.15 – 0.4 | 0.28 |
| Si | 0.15 – 0.4 | 0.28 |
| Cr | 3.75 – 4.5 | 4.1 |
| Wprimary hot-hardness element | 17.25 – 19 | 18 |
| V | 0.75 – 1.25 | 1 |
| Moresidual limit | ≤ 0.3 | — |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
H26-ANN — frequently asked
What is H26-ANN used for?
H26-ANN is typically used for hot extrusion dies, hot forging dies and inserts, hot shear blades and die-casting dies for brass/bronze. In short: highest tungsten wear resistance; runs up to 60–63 HRC; less tough than H25.
What is the yield strength of H26-ANN?
H26-ANN has a typical yield strength of 560 MPa (81.2 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 73% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is H26-ANN easy to machine?
Not especially — machinability is rated poor (32/100, worse than 87% of steel grades). Machine only in the annealed condition with rigid setups, low speeds and carbide or cobalt HSS tooling; the ~18% W and vanadium carbides are abrasive, so finish-grind with soft, friable alumina or CBN wheels after hardening.
Can H26-ANN be welded?
Not readily — weldability is rated poor (20/100). Fusion welding is limited to die repair — preheat to 400–500 °C, use matched or high-alloy filler, weld hot and immediately temper below the last tempering temperature to avoid cracking.
What surface finishes work on H26-ANN?
Salt-bath or gas nitriding and PVD TiAlN/CrN coatings are common for extrusion tooling; oil or phosphate protection is needed for storage since corrosion resistance is low.
Can H26-ANN be formed, bent or molded?
Cold forming is not practical; hot work between 1050 and 1150 °C, never below ~950 °C, and slow-cool/anneal at 870–900 °C after forging.
What is the maximum service temperature of H26-ANN?
H26-ANN is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between H26-ANN and H26-HR?
ANN is the default condition — standard mill supply condition for bar and forgings; machine tooling here, then harden and temper. HR: as-forged or hot-rolled stock supplied for further hot work or full anneal before machining; not a service condition. Yield strength is 560 MPa in ANN versus 760 MPa in HR.
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)
- ASM Handbook Vol.16 — Machining (tool steel machinability ratings) — ASM International (1989)
- Tool Steels, 5th Edition (Roberts, Krauss, Kennedy) — ASM International (1998)
- GB/T 1299 (tungsten hot-work grades) (2014)
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.