Steel T9
AISI/SAE T9
T9 is a plain carbon tool steel of the Chinese GB/T 1298 series at about 0.85–0.94 % C, sitting between T7 and T12 in the trade-off between wear resistance and toughness.
Reference datasheet — T9 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 A condition
T9 tempers and conditions
T9 is supplied in 8 conditions, soft to hard. A is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
High-grade quality | Specify the high-grade quality variant with lower phosphorus and sulphur and tighter control of inclusions and carbide non-uniformity for precision dies and cutting tools. | 395 | 650 | 22 | 62 HRC | 9.8 % IACS |
ADefault Solution annealed | Choose the spheroidize annealed as-supplied bar or plate for the lowest hardness (180 HB) and easiest turning, milling, drilling and cold working before final quench hardening. | 400 | 660 | 20 | 180 HB | — |
Hot rolled | Take hot rolled or hot forged untreated stock only as a blank; its network carbides require spheroidize annealing before machining or hardening. | 450 | 790 | 12 | 21 HRC | 9.4 % IACS |
Normalized | Normalize at 800–840 °C with air cooling to break up forging carbide networks and refine the structure in preparation for spheroidize annealing or quenching, not as a final state. | 470 | 830 | 10 | 25 HRC | 9.3 % IACS |
Cold drawn | Pick annealed-then-cold-drawn bar or cold rolled strip for tight size tolerance and smooth surface in small sections; hardness rises to 230 HB while elongation drops to 8%. | 620 | 800 | 8 | 20 HRC | 9.5 % IACS |
Q&T 45–52 HRC | Temper at 300–400 °C to 45–52 HRC when chisels, punches and spring parts see heavy impact; wear resistance is sacrificed for 1400 MPa yield and 4% elongation. | 1,400 | 1,650 | 4 | 49 HRC | — |
Q&T 56–60 HRC | Choose tempering at 200–250 °C to 56–60 HRC when blanking dies, shear blades and hand tools must absorb some impact, trading peak wear resistance for toughness. | 1,750 | 1,950 | 1 | 58 HRC | 8.6 % IACS |
Q&T 60–63 HRC | Use water quenching from 760–780 °C with 150–180 °C tempering for maximum hardness (60–63 HRC) and wear resistance in punches, chisels and woodworking blades; toughness is minimal. | 2,100 | 1 | 62 HRC | — |
What is T9?
T9 is a plain carbon tool steel of the Chinese GB/T 1298 series at about 0.85–0.94 % C, sitting between T7 and T12 in the trade-off between wear resistance and toughness. It is bought as spheroidize-annealed, hot-rolled, normalized and cold-drawn bar, in QT-62, QT-58 and QT-50 hardened conditions, and as the higher-purity T9A. Annealed values are 400 MPa yield, 660 MPa tensile, 20 % elongation and 180 HB, with useful service limited to about 300 °C because tempering softens the martensite. It is effectively non-weldable, water-hardening and shallow-hardening; use an alloy grade such as 9SiCr for thicker or distortion-sensitive tooling. T9 has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,400°C (2,552 °F). T9 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 60% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi).
What is T9 used for?
- punches
- dies
- cutting tools
- woodworking tools
Advantages
- Polishes to a fine finish — 72/100, better than 92% of steel grades
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
- High electrical conductivity — 9.6 % IACS, better than 78% of steel grades
Limitations
- Difficult to weld — 12/100, worse than 96% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
T9 properties
Typical room-temperature values for T9-A; bars are the position among steel grades.
Physical3
T9 has a density of 7.81 g/cm³ (0.282 lb/in³), lighter than 84% of steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
T9 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 60% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
T9 is rated for continuous service to 300°C (572 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical3
T9 conducts electricity at 9.6 % IACS, better than 78% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (8/100), worse than 99% of steel grades.
Sustainability4
Producing a kilogram of T9 takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
T9's machinability is fair (45/100, worse than 65% of steel grades); weldability not recommended (12/100); formability fair (35/100).
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. T9 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with T9
Is T9 easy to machine?
Turning, milling, drilling and tapping are all practical in the spheroidize-annealed condition (≤192 HB) using HSS or coated carbide with ample coolant; after hardening only grinding or EDM is possible.
Can T9 be welded?
Poor weldability — at about 0.9 % C martensite and cracking are almost unavoidable, so T9 is normally not welded. If repair is unavoidable, preheat 250–350 °C, use low-hydrogen consumables and temper immediately.
Can T9 be formed, bent or molded?
The annealed condition allows light cold bending and blanking, but formability is limited. Forge from 1050–1100 °C with a finishing temperature no lower than 800 °C, then slow-cool and spheroidize-anneal; harden from 760–780 °C in water or brine, noting the shallow hardening depth and high distortion and cracking risk.
T9 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 |
|---|---|---|
| CGB/T 1298 | 0.85 – 0.94 | 0.9 |
| Si | ≤ 0.35 | 0.22 |
| Mn | ≤ 0.4 | 0.25 |
| PT9A ≤0.030 | ≤ 0.04 | |
| ST9A ≤0.020 | ≤ 0.03 | |
| Crresidual element | ≤ 0.25 | |
| Niresidual element | ≤ 0.2 | |
| Curesidual element | ≤ 0.3 | |
| Fe | balance |
What surface finishes work on T9?
No corrosion resistance: specify black oxide (alkaline blackening), phosphating, chrome plating or rust-preventive oil. Hardened parts can be ground and polished to a mirror finish, but watch for grinding burn and temper softening.
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 T9 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- T9A
How much does T9 cost?
T9 is a budget-cost steel ($), cheaper than about 90% 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.
T9 — frequently asked
What is T9 used for?
T9 is typically used for punches, dies, cutting tools and woodworking tools. In short: mid-carbon T-series tool steel; balanced wear and toughness; water-hardening, shallow case.
What is the yield strength of T9?
T9 has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 660 MPa (95.7 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is T9 easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Turning, milling, drilling and tapping are all practical in the spheroidize-annealed condition (≤192 HB) using HSS or coated carbide with ample coolant; after hardening only grinding or EDM is possible.
Can T9 be welded?
Not readily — weldability is rated not recommended (12/100). Poor weldability — at about 0.9 % C martensite and cracking are almost unavoidable, so T9 is normally not welded. If repair is unavoidable, preheat 250–350 °C, use low-hydrogen consumables and temper immediately.
What surface finishes work on T9?
No corrosion resistance: specify black oxide (alkaline blackening), phosphating, chrome plating or rust-preventive oil. Hardened parts can be ground and polished to a mirror finish, but watch for grinding burn and temper softening.
Can T9 be formed, bent or molded?
The annealed condition allows light cold bending and blanking, but formability is limited. Forge from 1050–1100 °C with a finishing temperature no lower than 800 °C, then slow-cool and spheroidize-anneal; harden from 760–780 °C in water or brine, noting the shallow hardening depth and high distortion and cracking risk.
What is the maximum service temperature of T9?
T9 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between T9-A and T9 QT-58?
A is the default condition — choose the spheroidize annealed as-supplied bar or plate for the lowest hardness (180 HB) and easiest turning, milling, drilling and cold working before final quench hardening. QT-58: choose tempering at 200–250 °C to 56–60 HRC when blanking dies, shear blades and hand tools must absorb some impact, trading peak wear resistance for toughness. Yield strength is 400 MPa in A versus 1,750 MPa in QT-58.
How much does T9 cost?
T9 is a budget-cost steel ($), cheaper than about 90% 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
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4: Heat Treating (water-hardening tool steels, W1) — ASM International (1991)
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.