Steel 9Mn2V Q+T350
Hardness band
EN 9Mn2V · AISI/SAE O2
Q+T350 = oil quenched + tempered ~350 °C
Tougher condition for mold inserts, die holders and tooling with sharp corners; wear resistance drops noticeably.
Values for the Q+T350 condition
Other 9Mn2V tempers and conditions
9Mn2V is listed in 10 conditions; see the grade overview at 9Mn2V.
Compare all 10 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ADefault Solution annealed | Standard supply condition for bar, flat and plate — soft, machinable, ready for the customer's own oil hardening. | 420 | 720 | 15 | 217 HB | — |
Stress relieved | Intermediate step after rough machining of gauge bodies so that quench distortion stays within grinding allowance. | 430 | 730 | 14 | 19 HRC | 7 % IACS |
Hot rolled | Mill as-rolled black bar; must be annealed before machining because as-rolled hardness is high and uneven. | 560 | 900 | 10 | 29 HRC | 7 % IACS |
Cold drawn | Precision-ground/cold-drawn bright bar in the annealed state for small punches, gauge blanks and taps needing tight tolerance without machining. | 600 | 800 | 10 | 21 HRC | 7 % IACS |
Normalized | Used only as a grain-refining / structure-homogenizing step before annealing; too hard and brittle for service. | 650 | 1,000 | 8 | 31 HRC | 7 % IACS |
Oil quenched + tempered ~450 °C | Toughest usable heat-treated state — for die shanks, ejector components and parts that must survive impact rather than abrade. | 1,250 | 1,450 | 8 | 45 HRC | 6.9 % IACS |
Q+T350This page Oil quenched + tempered ~350 °C | Tougher condition for mold inserts, die holders and tooling with sharp corners; wear resistance drops noticeably. | 1,500 | 1,750 | 4 | 52 HRC | 6.7 % IACS |
Oil quenched + tempered ~250 °C | Choose when moderate shock loading is expected (small stamping dies, shear blades for thin stock). | 1,650 | 1,950 | 2.5 | 56 HRC | 6.4 % IACS |
Oil quenched + tempered ~200 °C | Most common working hardness for precision gauges and small cold-work dies — slightly tougher and dimensionally more stable than the 62 HRC condition. | 1,800 | 2,100 | 1.5 | 59 HRC | — |
Oil quenched 780–810 °C + tempered 150–180 °C | Maximum hardness and wear resistance for gauges, blanking punches and thread rolling dies where toughness demand is low. | 1,950 | 2,300 | 1 | 61 HRC | — |
What is 9Mn2V Q+T350?
9Mn2V Q+T350 is 9Mn2V heat treated to Q+T350 — tougher condition for mold inserts, die holders and tooling with sharp corners; wear resistance drops noticeably. 9Mn2V Q+T350 has a yield strength of 1,500 MPa (218 ksi) and a tensile strength of 1,750 MPa (254 ksi) — stronger than 97% of steel grades. Elongation at break is 4% and the elastic modulus is 208 GPa (30.2 Msi). 9Mn2V Q+T350 has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,420°C (2,588 °F). A is the default condition FabDigit quotes; Q+T350 is available on request or by drawing note.
Advantages
- High strength — 1,500 MPa (218 ksi), better than 97% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- Difficult to weld — 6/100, worse than 100% of steel grades
- Limited ductility — 4%, worse than 98% of steel grades
- Low fracture toughness — 22 MPa·√m (20 ksi·√in), worse than 98% of steel grades
- Limited formability — 6/100, worse than 98% of steel grades
- Difficult to machine — 18/100, worse than 97% of steel grades
9Mn2V Q+T350 properties
Typical room-temperature values for 9Mn2V Q+T350; 22 are specific to this condition. Other listed values are 9Mn2V reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
9Mn2V Q+T350 has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
9Mn2V Q+T350 has a yield strength of 1,500 MPa (218 ksi) and a tensile strength of 1,750 MPa (254 ksi) — stronger than 97% of steel grades. Elongation at break is 4% and the elastic modulus is 208 GPa (30.2 Msi).
Thermal6
9Mn2V Q+T350 is rated for continuous service to 300°C (572 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
9Mn2V Q+T350 conducts electricity at 6.7 % IACS, worse than 76% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 9Mn2V Q+T350 takes about 32 MJ of energy and emits 2.3 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 35%.
Manufacturability8
9Mn2V Q+T350's machinability is poor (18/100, worse than 97% of steel grades); weldability not recommended (6/100); formability not recommended (6/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 9Mn2V Q+T350
Is 9Mn2V easy to machine?
Machine only in the spheroidize-annealed state (≈210 HB); above 55 HRC finish by grinding, EDM or CBN turning.
Can 9Mn2V be welded?
Poor weldability — repair welding needs 300–350 °C preheat, matching high-C filler and immediate re-temper to avoid quench cracks.
Can 9Mn2V be formed, bent or molded?
Cold form only mildly in annealed condition; hot work at 1050–850 °C then slow cool, oil harden 780–810 °C with 150–200 °C temper for minimum size change.
What surface finishes work on 9Mn2V?
Takes a high polish for gauge and mold surfaces; protect with oil, black oxide, phosphating, thin hard chrome or nitriding since the steel offers no corrosion resistance.
9Mn2V 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 | 0.85 – 0.95 | 0.9 |
| Si | ≤ 0.4 | 0.25 |
| Mngives oil hardenability and low distortion | 1.7 – 2 | 1.85 |
| Vgrain refinement | 0.1 – 0.25 | 0.18 |
| Crresidual | ≤ 0.3 | — |
| Niresidual | ≤ 0.25 | — |
| Curesidual | ≤ 0.3 | — |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
9Mn2V Q+T350 — frequently asked
What is 9Mn2V Q+T350 used for?
9Mn2V Q+T350 is typically used for precision gauges, small molds and cutting dies. In short: lowest-distortion oil-hardening grade; best machinability in family; shallow hardenability, small sections.
What is the yield strength of 9Mn2V Q+T350?
9Mn2V Q+T350 has a typical yield strength of 1,500 MPa (218 ksi) and a tensile strength of 1,750 MPa (254 ksi) — stronger than 97% of steel grades. Strength varies by condition: see the 10 listed tempers.
Is 9Mn2V Q+T350 easy to machine?
Not especially — machinability is rated poor (18/100, worse than 97% of steel grades). Machine only in the spheroidize-annealed state (≈210 HB); above 55 HRC finish by grinding, EDM or CBN turning.
Can 9Mn2V Q+T350 be welded?
Not readily — weldability is rated not recommended (6/100). Poor weldability — repair welding needs 300–350 °C preheat, matching high-C filler and immediate re-temper to avoid quench cracks.
What surface finishes work on 9Mn2V Q+T350?
Takes a high polish for gauge and mold surfaces; protect with oil, black oxide, phosphating, thin hard chrome or nitriding since the steel offers no corrosion resistance.
Can 9Mn2V Q+T350 be formed, bent or molded?
Cold form only mildly in annealed condition; hot work at 1050–850 °C then slow cool, oil harden 780–810 °C with 150–200 °C temper for minimum size change.
What is the maximum service temperature of 9Mn2V Q+T350?
9Mn2V Q+T350 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 9Mn2V-A and 9Mn2V-N?
A is the default condition — standard supply condition for bar, flat and plate — soft, machinable, ready for the customer's own oil hardening. N: used only as a grain-refining / structure-homogenizing step before annealing; too hard and brittle for service. Yield strength is 420 MPa in A versus 650 MPa in N.
Sources
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (tool steels) — ASM International (1990)
- Tool Steels, 5th ed. (O-series oil-hardening steels) — ASM International (1998)
- ASTM A681 — Alloy Tool Steels (Type O2) — ASTM (2015)
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.