Steel 9Mn2V-SR (Stress relieved)
Heat-treated state
EN 9Mn2V · AISI/SAE O2
Intermediate step after rough machining of gauge bodies so that quench distortion stays within grinding allowance.
Values for the SR 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 | — |
SRThis page 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 |
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-SR?
9Mn2V-SR is 9Mn2V heat treated to SR — intermediate step after rough machining of gauge bodies so that quench distortion stays within grinding allowance. 9Mn2V-SR has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 730 MPa (106 ksi) — weaker than 51% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi). 9Mn2V-SR 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; SR is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 70/100, better than 87% of steel grades
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Low fracture toughness — 46 MPa·√m (41.9 ksi·√in), worse than 88% of steel grades
- Difficult to weld — 18/100, worse than 87% of steel grades
- Limited ductility — 14%, worse than 75% of steel grades
- Poor heat conductor — 35 W/m·K (20.2 BTU/hr·ft·°F), worse than 75% of steel grades
9Mn2V-SR properties
Typical room-temperature values for 9Mn2V-SR; 23 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-SR 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-SR has a yield strength of 430 MPa (62.4 ksi) and a tensile strength of 730 MPa (106 ksi) — weaker than 51% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
9Mn2V-SR is rated for continuous service to 200°C (392 °F). It conducts heat at 35 W/m·K (20.2 BTU/hr·ft·°F), worse than 75% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
9Mn2V-SR conducts electricity at 7 % IACS, worse than 74% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 9Mn2V-SR 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-SR's machinability is fair (54/100, better than 54% of steel grades); weldability poor (18/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 9Mn2V-SR
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-SR — frequently asked
What is 9Mn2V-SR used for?
9Mn2V-SR 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-SR?
9Mn2V-SR has a typical yield strength of 430 MPa (62.4 ksi) and a tensile strength of 730 MPa (106 ksi) — weaker than 51% of steel grades. Strength varies by condition: see the 10 listed tempers.
Is 9Mn2V-SR easy to machine?
Reasonably — machinability is rated fair (54/100, better than 54% of steel grades). Machine only in the spheroidize-annealed state (≈210 HB); above 55 HRC finish by grinding, EDM or CBN turning.
Can 9Mn2V-SR be welded?
Not readily — weldability is rated poor (18/100). 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-SR?
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-SR 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-SR?
9Mn2V-SR is rated for continuous use to about 200°C (392 °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.