Steel W9Mo3Cr4V QT-NIT
Finish state
QT-NIT = hardened, tempered + surface treated
Choose when tool life is limited by adhesive wear — core stays 63–64 HRC while the 10–30 µm case reaches 1100–1300 HV.
Values for the QT-NIT condition
Other W9Mo3Cr4V tempers and conditions
W9Mo3Cr4V is listed in 6 conditions; see the grade overview at W9Mo3Cr4V.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hardened & tempered, 64–66 HRC | High austenitizing (~1230–1240 °C) plus 3× temper for maximum wear resistance and red hardness in continuous-cut tools; least tough. | — | — | — | 66 HRC | 20 W/m·K |
ANNDefault Annealed | Standard delivery condition for bar and blanks — soft enough to machine before hardening. | 550 | 850 | 18 | 240 HB | 24 W/m·K |
Cold drawn, annealed | Pick for small-diameter precision blanks (drill/tap stock) where size tolerance and surface finish matter. | 700 | 950 | 12 | 24 HRC | 3.1 % IACS |
Hardened & tempered, 60–62 HRC | Lower austenitizing (~1190 °C) / higher temper for interrupted cuts, taps, broaches and cold-work punches needing shock resistance. | — | 2,000 | 1 | 61 HRC | 21 W/m·K |
QT-NITThis page Hardened, tempered + surface treated | Choose when tool life is limited by adhesive wear — core stays 63–64 HRC while the 10–30 µm case reaches 1100–1300 HV. | 2,000 | 2,200 | 1 | 64 HRC | 2.6 % IACS |
Hardened & tempered, 63–64 HRC | The usual working hardness for drills, end mills, reamers and saw blades — balanced wear resistance and toughness. | — | 2,200 | 0.5 | 64 HRC | 21 W/m·K |
What is W9Mo3Cr4V QT-NIT?
W9Mo3Cr4V QT-NIT is W9Mo3Cr4V supplied in the QT-NIT condition — choose when tool life is limited by adhesive wear — core stays 63–64 HRC while the 10–30 µm case reaches 1100–1300 HV. W9Mo3Cr4V QT-NIT has a yield strength of 2,000 MPa (290 ksi) and a tensile strength of 2,200 MPa (319 ksi) — stronger than 100% of steel grades. Elongation at break is 1% and the elastic modulus is 225 GPa (32.6 Msi). W9Mo3Cr4V QT-NIT has a density of 8.3 g/cm³ (0.3 lb/in³), heavier than 99% of steel grades. It melts at 1,260°C (2,300 °F). ANN is the default condition FabDigit quotes; QT-NIT is available on request or by drawing note.
Advantages
- High strength — 2,000 MPa (290 ksi), better than 100% of steel grades
- High service temperature — 600°C (1,112 °F), better than 98% of steel grades
- Polishes to a fine finish — 75/100, better than 94% of steel grades
- Good corrosion resistance — 25/100, better than 92% of steel grades
Limitations
- Difficult to machine — 3/100, worse than 100% of steel grades
- Limited formability — 2/100, worse than 100% of steel grades
- Limited ductility — 1%, worse than 99% 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
W9Mo3Cr4V QT-NIT properties
Typical room-temperature values for W9Mo3Cr4V QT-NIT; 21 are specific to this condition. Other listed values are W9Mo3Cr4V reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
W9Mo3Cr4V QT-NIT has a density of 8.3 g/cm³ (0.3 lb/in³), heavier than 99% of steel grades. It melts at 1,260°C (2,300 °F).
Mechanical12
W9Mo3Cr4V QT-NIT has a yield strength of 2,000 MPa (290 ksi) and a tensile strength of 2,200 MPa (319 ksi) — stronger than 100% of steel grades. Elongation at break is 1% and the elastic modulus is 225 GPa (32.6 Msi).
Thermal6
W9Mo3Cr4V QT-NIT is rated for continuous service to 600°C (1,112 °F). It conducts heat at 22 W/m·K (12.7 BTU/hr·ft·°F), worse than 93% of steel grades. Thermal expansion is 10.7 µm/m·K (5.94 µin/in·°F).
Electrical2
W9Mo3Cr4V QT-NIT has an electrical resistivity of 6.5×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is poor (25/100), better than 92% of steel grades.
Sustainability4
Producing a kilogram of W9Mo3Cr4V QT-NIT takes about 60 MJ of energy and emits 4.2 kg of CO₂ — more than 96% of steel grades. Typical recycled content is 35%.
Manufacturability8
W9Mo3Cr4V QT-NIT's machinability is not recommended (3/100, worse than 100% of steel grades); weldability not recommended (10/100); formability not recommended (2/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with W9Mo3Cr4V QT-NIT
Is W9Mo3Cr4V easy to machine?
Machine only in the annealed (≤255 HB) state with sharp carbide or cobalt HSS tooling, rigid setup and flood coolant; after hardening it is grind/EDM only.
Can W9Mo3Cr4V be welded?
Not a structural weld grade — repair with TIG or laser using matching HSS filler, preheat 500–550 °C and re-temper immediately.
Can W9Mo3Cr4V be formed, bent or molded?
Hot forge 1120–1150 °C down to ~900 °C with slow furnace cooling; cold forming is impractical, harden 1200–1240 °C in salt/vacuum and temper 540–560 °C three times.
What surface finishes work on W9Mo3Cr4V?
Requires rust protection: black oxide, phosphate, steam-oxide, nitriding or TiN/TiAlN PVD; hardened surfaces polish and grind to fine finishes for cutting edges.
W9Mo3Cr4V 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 | 0.77 – 0.87 | 0.82 |
| Si | 0.2 – 0.4 | 0.3 |
| Mn | 0.2 – 0.4 | 0.3 |
| Cr | 3.8 – 4.4 | 4.1 |
| W | 8.5 – 9.5 | 9 |
| Mo | 2.7 – 3.3 | 3 |
| V | 1.3 – 1.7 | 1.5 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
W9Mo3Cr4V QT-NIT — frequently asked
What is W9Mo3Cr4V QT-NIT used for?
W9Mo3Cr4V QT-NIT is typically used for drills, end mills and broaches. In short: general-purpose cutting HSS; tougher than high-vanadium HSS; easier to grind than M3.
What is the yield strength of W9Mo3Cr4V QT-NIT?
W9Mo3Cr4V QT-NIT has a typical yield strength of 2,000 MPa (290 ksi) and a tensile strength of 2,200 MPa (319 ksi) — stronger than 100% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is W9Mo3Cr4V QT-NIT easy to machine?
Not especially — machinability is rated not recommended (3/100, worse than 100% of steel grades). Machine only in the annealed (≤255 HB) state with sharp carbide or cobalt HSS tooling, rigid setup and flood coolant; after hardening it is grind/EDM only.
Can W9Mo3Cr4V QT-NIT be welded?
Not readily — weldability is rated not recommended (10/100). Not a structural weld grade — repair with TIG or laser using matching HSS filler, preheat 500–550 °C and re-temper immediately.
What surface finishes work on W9Mo3Cr4V QT-NIT?
Requires rust protection: black oxide, phosphate, steam-oxide, nitriding or TiN/TiAlN PVD; hardened surfaces polish and grind to fine finishes for cutting edges.
Can W9Mo3Cr4V QT-NIT be formed, bent or molded?
Hot forge 1120–1150 °C down to ~900 °C with slow furnace cooling; cold forming is impractical, harden 1200–1240 °C in salt/vacuum and temper 540–560 °C three times.
What is the maximum service temperature of W9Mo3Cr4V QT-NIT?
W9Mo3Cr4V QT-NIT is rated for continuous use to about 600°C (1,112 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between W9Mo3Cr4V-ANN and W9Mo3Cr4V QT-NIT?
ANN is the default condition — standard delivery condition for bar and blanks — soft enough to machine before hardening. QT-NIT: choose when tool life is limited by adhesive wear — core stays 63–64 HRC while the 10–30 µm case reaches 1100–1300 HV. Yield strength is 550 MPa in ANN versus 2,000 MPa in QT-NIT.
Sources
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (High-Speed Tool Steels) — ASM International (1990)
- ASTM A600 — Standard Specification for Tool Steel High Speed — ASTM (2016)
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.