Steel F2 HT-56-58
Hardness band
UNS T60602
HT-56-58 = hardened & Tempered 56–58 HRC
Highest-toughness usable hardness for F2; used where chipping of the cutting edge is the failure mode.
Values for the HT-56-58 condition
Other F2 tempers and conditions
F2 is listed in 6 conditions; see the grade overview at F2.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefault Annealed | Standard supply condition for machining, grinding and forming of the tool before hardening. | 430 | 760 | 22 | 223 HB | — |
Cold Drawn Annealed | Choose for close-tolerance small bar and drill-rod-type stock that will be hardened after light machining. | 600 | 830 | 12 | 24 HRC | 8 % IACS |
HT-56-58This page Hardened & Tempered 56–58 HRC | Highest-toughness usable hardness for F2; used where chipping of the cutting edge is the failure mode. | 1,650 | 1,850 | 2 | 57 HRC | — |
Hardened & Tempered 60–62 HRC | Slightly tougher working hardness for cutting tools and dies that see light impact. | 1,800 | 2,000 | 1 | 61 HRC | — |
As-Quenched | Intermediate condition only — maximum hardness but highly stressed and crack-prone; temper immediately. | 1,900 | 2,000 | 0.5 | 66 HRC | 6 % IACS |
Hardened & Tempered 62–64 HRC | Standard working condition for maximum wear resistance and edge holding on light, shock-free tooling. | 1,900 | 2,100 | 1 | 63 HRC | — |
What is F2 HT-56-58?
F2 HT-56-58 is F2 heat treated to HT-56-58 — highest-toughness usable hardness for F2; used where chipping of the cutting edge is the failure mode. F2 HT-56-58 has a yield strength of 1,650 MPa (239 ksi) and a tensile strength of 1,850 MPa (268 ksi) — stronger than 99% of steel grades. Elongation at break is 2% and the elastic modulus is 205 GPa (29.7 Msi). F2 HT-56-58 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 93% of steel grades. It melts at 1,400°C (2,552 °F). ANN is the default condition FabDigit quotes; HT-56-58 is available on request or by drawing note.
Advantages
- High strength — 1,650 MPa (239 ksi), better than 99% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- Difficult to machine — 8/100, worse than 100% of steel grades
- Limited ductility — 2%, worse than 99% of steel grades
- Difficult to weld — 12/100, worse than 96% of steel grades
- High embodied carbon — 2.7 kg CO₂/kg, worse than 89% of steel grades
- Poor heat conductor — 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 83% of steel grades
F2 HT-56-58 properties
Typical room-temperature values for F2 HT-56-58; 11 are specific to this condition. Other listed values are F2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
F2 HT-56-58 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 93% of steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
F2 HT-56-58 has a yield strength of 1,650 MPa (239 ksi) and a tensile strength of 1,850 MPa (268 ksi) — stronger than 99% of steel grades. Elongation at break is 2% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
F2 HT-56-58 is rated for continuous service to 260°C (500 °F). It conducts heat at 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 83% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
F2 HT-56-58 conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of F2 HT-56-58 takes about 36 MJ of energy and emits 2.7 kg of CO₂ — more than 89% of steel grades. Typical recycled content is 30%.
Manufacturability7
F2 HT-56-58's machinability is not recommended (8/100, worse than 100% of steel grades); weldability not recommended (12/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with F2 HT-56-58
Is F2 easy to machine?
Machine only in the spheroidize-annealed condition (~30 % of AISI 1212); the dispersed tungsten carbides are abrasive, so use rigid setups, sharp carbide or coated tooling and generous coolant; finish grind after hardening with soft, free-cutting wheels to avoid grinding cracks.
Can F2 be welded?
Essentially not weldable for structural purposes; only small repair welds with matched high-C/W filler, preheat 300–350 °C, immediate post-weld temper — otherwise quench cracking is near certain.
Can F2 be formed, bent or molded?
Hot forge 1010–1120 °C, stop above 900 °C and cool slowly, then anneal at 760–790 °C; cold forming is limited to light bending of thin annealed stock.
What surface finishes work on F2?
Takes a fine polish and can be black-oxided, phosphated or nitrided; must be oiled or plated for storage because it has no corrosion resistance. Harden 790–845 °C, brine/water quench, temper 150–290 °C immediately.
F2 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 |
|---|---|---|
| Chigh carbon for carbide formation | 1.2 – 1.4 | 1.3 |
| Wprincipal alloying addition vs F1 | 3 – 4 | 3.5 |
| Mn | 0.1 – 0.4 | 0.25 |
| Si | 0.1 – 0.4 | 0.25 |
| Croptional / permitted addition | 0.2 – 0.4 | 0.3 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
F2 HT-56-58 — frequently asked
What is F2 HT-56-58 used for?
F2 HT-56-58 is typically used for files, small punches, light blanking dies and wear-resistant hand tools. In short: higher tungsten than F1; wear-resistant water-hardening grade; abrasive to machine.
What is the yield strength of F2 HT-56-58?
F2 HT-56-58 has a typical yield strength of 1,650 MPa (239 ksi) and a tensile strength of 1,850 MPa (268 ksi) — stronger than 99% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is F2 HT-56-58 easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 100% of steel grades). Machine only in the spheroidize-annealed condition (~30 % of AISI 1212); the dispersed tungsten carbides are abrasive, so use rigid setups, sharp carbide or coated tooling and generous coolant; finish grind after hardening with soft, free-cutting wheels to avoid grinding cracks.
Can F2 HT-56-58 be welded?
Not readily — weldability is rated not recommended (12/100). Essentially not weldable for structural purposes; only small repair welds with matched high-C/W filler, preheat 300–350 °C, immediate post-weld temper — otherwise quench cracking is near certain.
What surface finishes work on F2 HT-56-58?
Takes a fine polish and can be black-oxided, phosphated or nitrided; must be oiled or plated for storage because it has no corrosion resistance. Harden 790–845 °C, brine/water quench, temper 150–290 °C immediately.
Can F2 HT-56-58 be formed, bent or molded?
Hot forge 1010–1120 °C, stop above 900 °C and cool slowly, then anneal at 760–790 °C; cold forming is limited to light bending of thin annealed stock.
What is the maximum service temperature of F2 HT-56-58?
F2 HT-56-58 is rated for continuous use to about 260°C (500 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between F2-ANN and F2-AQ?
ANN is the default condition — standard supply condition for machining, grinding and forming of the tool before hardening. AQ: intermediate condition only — maximum hardness but highly stressed and crack-prone; temper immediately. Yield strength is 430 MPa in ANN versus 1,900 MPa in AQ.
Sources
- 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)
- ASTM A686 — Standard Specification for Tool Steel, Carbon — ASTM International (2020)
- SAE J437/J438 — Tool and Die Steels (composition and UNS designations) — SAE International (2019)
- UNS T60602 alloy record (Metals & Alloys in the Unified Numbering System) — SAE/ASTM (2017)
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.