Steel T2 HT-64
Heat-treated state
AISI/SAE T2 · UNS T12002
HT-64 = hardened & tempered 63–65 HRC
General working hardness for cutting tools where some toughness is wanted along with high wear resistance.
Values for the HT-64 condition
Other T2 tempers and conditions
T2 is listed in 5 conditions; see the grade overview at T2.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ANNDefault Annealed | Standard as-supplied condition for bars and blanks: soft enough to machine tool bodies before hardening. | 570 | 900 | 20 | 235 HB | — |
Cold drawn / ground annealed bar | Precision-ground or cold-drawn annealed bar for tool blanks needing close size and straightness before hardening. | 650 | 950 | 15 | 24 HRC | 3.1 % IACS |
HT-64This page Hardened & tempered 63–65 HRC | General working hardness for cutting tools where some toughness is wanted along with high wear resistance. | 1,900 | 2,100 | 0.5 | 64 HRC | 22 W/m·K |
Hardened, tempered + surface treated | Pick when tool life is limited by adhesive wear or built-up edge; core stays at working hardness while the case reaches 1000–1200 HV. | 1,900 | 2,000 | 0.5 | 64 HRC | 2.8 % IACS |
Hardened & tempered 65–66 HRC | Top-hardness condition for finishing cuts on abrasive or hard workpieces; lowest toughness, avoid interrupted cuts. | 2,000 | 2,100 | 0.5 | 66 HRC | 2.9 % IACS |
What is T2 HT-64?
T2 HT-64 is T2 heat treated to HT-64 — general working hardness for cutting tools where some toughness is wanted along with high wear resistance. T2 HT-64 has a yield strength of 1,900 MPa (276 ksi) and a tensile strength of 2,100 MPa (305 ksi) — stronger than 100% of steel grades. Elongation at break is 0.5% and the elastic modulus is 220 GPa (31.9 Msi). T2 HT-64 has a density of 8.67 g/cm³ (0.313 lb/in³), heavier than 99% of steel grades. It melts at 1,425°C (2,597 °F). ANN is the default condition FabDigit quotes; HT-64 is available on request or by drawing note.
Advantages
- High strength — 1,900 MPa (276 ksi), better than 100% of steel grades
- High service temperature — 550°C (1,022 °F), better than 95% of steel grades
- Good corrosion resistance — 22/100, better than 90% of steel grades
Limitations
- Limited ductility — 0.5%, worse than 100% of steel grades
- Difficult to machine — 8/100, worse than 100% of steel grades
- Difficult to weld — 10/100, worse than 99% of steel grades
- High embodied carbon — 4.2 kg CO₂/kg, worse than 95% of steel grades
- Poor heat conductor — 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades
T2 HT-64 properties
Typical room-temperature values for T2 HT-64; 17 are specific to this condition. Other listed values are T2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
T2 HT-64 has a density of 8.67 g/cm³ (0.313 lb/in³), heavier than 99% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
T2 HT-64 has a yield strength of 1,900 MPa (276 ksi) and a tensile strength of 2,100 MPa (305 ksi) — stronger than 100% of steel grades. Elongation at break is 0.5% and the elastic modulus is 220 GPa (31.9 Msi).
Thermal6
T2 HT-64 is rated for continuous service to 550°C (1,022 °F). It conducts heat at 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades. Thermal expansion is 11.2 µm/m·K (6.22 µin/in·°F).
Electrical3
T2 HT-64 conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental2
Corrosion resistance is poor (22/100), better than 90% of steel grades.
Sustainability4
Producing a kilogram of T2 HT-64 takes about 58 MJ of energy and emits 4.2 kg of CO₂ — more than 95% of steel grades. Typical recycled content is 40%.
Manufacturability8
T2 HT-64's machinability is not recommended (8/100, worse than 100% of steel grades); weldability not recommended (10/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with T2 HT-64
Is T2 easy to machine?
Machine only in the annealed condition (~230 HB) with sharp cobalt-HSS or coated carbide, low speed and rigid setup; after hardening only grinding or EDM, and the 2% V content makes grinding wheels load faster than on T1.
Can T2 be welded?
Not a structural weld metal — repair-weld only with matching HSS filler, 500–550 °C preheat, interpass held hot, and an immediate triple temper to avoid quench cracking.
Can T2 be formed, bent or molded?
Hot forge 1100–1150 °C, never below ~900 °C, slow-cool then anneal at 870–900 °C; cold forming is impractical.
What surface finishes work on T2?
Harden 1260–1280 °C (salt/vacuum, preheat steps), quench in oil/gas, temper 3× at 540–560 °C; finish with grinding plus black oxide, steam treat, nitriding or TiN/TiAlN PVD for wear and rust protection.
T2 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 | 0.8 – 0.9 | 0.85 |
| Mn | 0.2 – 0.4 | 0.3 |
| Si | 0.2 – 0.4 | 0.3 |
| Cr | 3.75 – 4.5 | 4.1 |
| Wprimary red-hardness element | 17.5 – 19 | 18.2 |
| Vhigher than T1 — MC carbides for wear resistance | 1.8 – 2.4 | 2.1 |
| Mooptional/residual | ≤ 1 | 0.5 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
T2 HT-64 — frequently asked
What is T2 HT-64 used for?
T2 HT-64 is typically used for cutting tools, reamers, form tools and lathe tools. In short: higher-vanadium T1; wear-resistant tungsten HSS; grinds slower than T1.
What is the yield strength of T2 HT-64?
T2 HT-64 has a typical yield strength of 1,900 MPa (276 ksi) and a tensile strength of 2,100 MPa (305 ksi) — stronger than 100% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is T2 HT-64 easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 100% of steel grades). Machine only in the annealed condition (~230 HB) with sharp cobalt-HSS or coated carbide, low speed and rigid setup; after hardening only grinding or EDM, and the 2% V content makes grinding wheels load faster than on T1.
Can T2 HT-64 be welded?
Not readily — weldability is rated not recommended (10/100). Not a structural weld metal — repair-weld only with matching HSS filler, 500–550 °C preheat, interpass held hot, and an immediate triple temper to avoid quench cracking.
What surface finishes work on T2 HT-64?
Harden 1260–1280 °C (salt/vacuum, preheat steps), quench in oil/gas, temper 3× at 540–560 °C; finish with grinding plus black oxide, steam treat, nitriding or TiN/TiAlN PVD for wear and rust protection.
Can T2 HT-64 be formed, bent or molded?
Hot forge 1100–1150 °C, never below ~900 °C, slow-cool then anneal at 870–900 °C; cold forming is impractical.
What is the maximum service temperature of T2 HT-64?
T2 HT-64 is rated for continuous use to about 550°C (1,022 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between T2-ANN and T2 HT-66?
ANN is the default condition — standard as-supplied condition for bars and blanks: soft enough to machine tool bodies before hardening. HT-66: top-hardness condition for finishing cuts on abrasive or hard workpieces; lowest toughness, avoid interrupted cuts. Yield strength is 570 MPa in ANN versus 2,000 MPa in HT-66.
Sources
- ASTM A600 — Tool Steel High Speed Tool Steels — ASTM International (2021)
- GB/T 9943 (W18Cr4V / W18Cr4V2 series) (2008)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys (Tool Steels) — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- Tool Steels, 5th ed. — ASM International (1998)
- Tungsten high-speed steel bar datasheets (T1/T2 type) — Böhler / Erasteel / (2023)
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.