Steel T5
AISI/SAE T5 · UNS T12005
T5 is a tungsten-based high-speed steel (T12005) with about 8% cobalt and increased vanadium for red-hardness and wear resistance in hot cutting.
Reference datasheet — T5 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the ANN condition
T5 tempers and conditions
T5 is supplied in 5 conditions, soft to hard. ANN is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hardened & tempered 60–62 HRC | Softer, tougher setting for interrupted cuts, large-section tools and hot-work punches prone to chipping. | 61 HRC | — | |||
ANNDefault Annealed | The as-supplied machinable condition for cutting blanks, forgings and dies before hardening. | 590 | 900 | 12 | 255 HB | 22 W/m·K |
Hardened & tempered 63–65 HRC | Standard working hardness for general heavy-duty cutting tools in T5; best balance of red-hardness and residual toughness. | 1,950 | 2,100 | 0.5 | 64 HRC | 20 W/m·K |
Hardened & tempered 65–66 HRC | Maximum-hardness condition for abrasive hot cutting and hogging where edge wear, not chipping, controls tool life. | 1,950 | 2,050 | 0.3 | 66 HRC | 2.9 % IACS |
Hardened + deep cryogenic treated + tempered | Adds a −80 to −196 °C sub-zero step to convert retained austenite; used for dimensional stability and extra wear life on precision tooling. | 1,950 | 2,050 | 0.3 | 65 HRC | 2.9 % IACS |
What is T5?
T5 is a tungsten-based high-speed steel (T12005) with about 8% cobalt and increased vanadium for red-hardness and wear resistance in hot cutting. It is chosen for heavy roughing and high-temperature turning tools, and is stocked as annealed bar and flat (255 HB, 900 MPa tensile, 590 MPa yield, 12% elongation, 214 GPa modulus) with hardened conditions at 60, 63 and 65 HRC plus a cryogenic option. Limits are poor grindability from the high V+Co content, low toughness, essentially no weldability or cold formability, and no corrosion resistance; thermal conductivity is 22 W/m·K and the listed maximum service temperature is 400 °C. M42 is the usual cobalt alternative when grinding cost matters. T5 has a density of 8.75 g/cm³ (0.316 lb/in³), heavier than 100% of steel grades. It melts at 1,400°C (2,552 °F). T5 has a yield strength of 590 MPa (85.6 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 76% of steel grades. Elongation at break is 12% and the elastic modulus is 214 GPa (31 Msi).
What is T5 used for?
- heavy roughing tools
- hot-hardness cutting tools
- broaches
- high-temperature turning tools
Advantages
- High strength — 590 MPa (85.6 ksi), better than 76% of steel grades
Limitations
- High embodied carbon — 7 kg CO₂/kg, worse than 99% of steel grades
- Low fracture toughness — 22 MPa·√m (20 ksi·√in), worse than 98% of steel grades
- Poor heat conductor — 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades
- Limited formability — 12/100, worse than 92% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
T5 properties
Typical room-temperature values for T5-ANN; bars are the position among steel grades.
Physical3
T5 has a density of 8.75 g/cm³ (0.316 lb/in³), heavier than 100% of steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
T5 has a yield strength of 590 MPa (85.6 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 76% of steel grades. Elongation at break is 12% and the elastic modulus is 214 GPa (31 Msi).
Thermal6
T5 is rated for continuous service to 400°C (752 °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 µm/m·K (6.11 µin/in·°F).
Electrical3
T5 conducts electricity at 3.1 % IACS, worse than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (18/100), better than 83% of steel grades.
Sustainability4
Producing a kilogram of T5 takes about 100 MJ of energy and emits 7 kg of CO₂ — more than 99% of steel grades. Typical recycled content is 35%.
Manufacturability7
T5's machinability is poor (32/100, worse than 87% of steel grades); weldability poor (15/100); formability not recommended (12/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. T5 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with T5
Is T5 easy to machine?
Machine only in the annealed state with rigid setups, low speeds and positive-rake carbide or cobalt-HSS tooling; hardened T5 is finished by CBN/alumina grinding, and its high V + Co content makes grindability poor (burn and wheel wear).
Can T5 be welded?
Essentially a repair-only operation: preheat 500–550 °C, use matched HSS or Co-HSS filler, weld hot, cool slowly and immediately re-temper at the original tempering temperature to avoid quench cracks.
Can T5 be formed, bent or molded?
No cold forming; hot forge from 1050–1150 °C, stop above 950 °C, cool slowly and always full-anneal (860–900 °C, slow cool) after forging.
T5 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 | 0.75 – 0.85 | 0.8 |
| Mn | 0.2 – 0.4 | 0.3 |
| Si | 0.2 – 0.4 | 0.3 |
| Cr | 3.75 – 5 | 4.2 |
| W | 17.5 – 19 | 18.25 |
| V | 1.8 – 2.4 | 2 |
| Cohigh-cobalt for red hardness | 7 – 9.5 | 8 |
| Mo | 0.5 – 1.25 | 0.8 |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on T5?
Not anodizable; protect with oil, black oxide, steam oxide or phosphate, or apply TiN/TiAlN/AlCrN PVD coatings below the tempering temperature for cutting tools.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel T5 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- T12005
How much does T5 cost?
T5 is a high-cost steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
T5 — frequently asked
What is T5 used for?
T5 is typically used for heavy roughing tools, hot-hardness cutting tools, broaches and high-temperature turning tools. In short: high-cobalt tungsten HSS; red-hardness roughing grade; poor grindability.
What is the yield strength of T5?
T5 has a typical yield strength of 590 MPa (85.6 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 76% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is T5 easy to machine?
Not especially — machinability is rated poor (32/100, worse than 87% of steel grades). Machine only in the annealed state with rigid setups, low speeds and positive-rake carbide or cobalt-HSS tooling; hardened T5 is finished by CBN/alumina grinding, and its high V + Co content makes grindability poor (burn and wheel wear).
Can T5 be welded?
Not readily — weldability is rated poor (15/100). Essentially a repair-only operation: preheat 500–550 °C, use matched HSS or Co-HSS filler, weld hot, cool slowly and immediately re-temper at the original tempering temperature to avoid quench cracks.
What surface finishes work on T5?
Not anodizable; protect with oil, black oxide, steam oxide or phosphate, or apply TiN/TiAlN/AlCrN PVD coatings below the tempering temperature for cutting tools.
Can T5 be formed, bent or molded?
No cold forming; hot forge from 1050–1150 °C, stop above 950 °C, cool slowly and always full-anneal (860–900 °C, slow cool) after forging.
What is the maximum service temperature of T5?
T5 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 T5-ANN and T5 HT-63?
ANN is the default condition — the as-supplied machinable condition for cutting blanks, forgings and dies before hardening. HT-63: standard working hardness for general heavy-duty cutting tools in T5; best balance of red-hardness and residual toughness. Yield strength is 590 MPa in ANN versus 1,950 MPa in HT-63.
How much does T5 cost?
T5 is a high-cost steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A600 — Standard Specification for Tool Steel High Speed — ASTM International (2016)
- 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)
- High-speed steel grade datasheets (T-series, Co-bearing) — Erasteel / Böhler-Uddeholm (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.