9CrWMn — 9CrWMn Oil-Hardening Cold Work Tool Steel — is a cold work tool steel supplied at HRC 58-62. Its chemistry centres on 0.85-1.00% carbon, 0.40-0.60% chromium and 0.10-0.20% vanadium. Oil-quench wear resistance with excellent machinability. It is available from stock as precision-ground hardened round bar from Φ2 to Φ100 mm, and as machined rotary die bodies made to drawing.
What 9CrWMn is, and where it fits
Grade selection is about matching the dominant failure mode. 9CrWMn's role in the range is clear: machinability and short-run economy. If your dies fail by gradual wear, prioritise wear resistance. If they chip or crack, prioritise toughness — which usually means accepting a slightly lower hardness.
- GB (China)
- 9CrWMn
- AISI / ASTM (US)
- O1 / T31501
- JIS (Japan)
- SKS3
- DIN / W-Nr (Germany)
- 1.2510 / 100MnCrW4
- BS (UK)
- BO1
- UNI (Italy)
- 95MnWCr5KU
- GOST (Russia)
- 9KhVG
Working hardness and what each band is for
9CrWMn hardens across a wide window, and the hardness you choose changes the tool's behaviour more than the grade does. Higher hardness buys wear resistance and edge retention at the cost of toughness; lower hardness does the reverse.
| Band | Hardness | Typical use |
|---|---|---|
| Primary working range | 58 - 62 | First choice for standard production tooling |
| Secondary range | 55 - 58 | Where the application calls for more toughness or more wear resistance |
9CrWMn for hardened round bar and rotary dies
| Product line | Suitability | Working hardness | Typical applications |
|---|---|---|---|
| hardened round bar | Recommended (3/5) | HRC 58-62 | Economy die tooling, Stamping dies, Gauges & measuring tools |
| custom rotary dies | Available but not first choice (2/5) | HRC 58-62 | Economy rotary dies, Low-speed slitting rollers |
When to choose 9CrWMn — and when not to
| Choose 9CrWMn when… | Look at another grade when… |
|---|---|
| Prototype and short-run tooling where machining speed matters more than die life | Production tooling running millions of strokes — wear resistance is the lowest here |
| Gauges, fixtures and low-volume blanking where 9CrWMn's machinability shortens lead time | High-speed cutting where edge temperature is significant |
| In-house hardening is required — 9CrWMn is the most forgiving grade to heat treat |
Related grades and guides for 9CrWMn
9CrWMn FAQ
9CrWMn (9CrWMn Oil-Hardening Cold Work Tool Steel) is used for oil-hardening, easy machining, economy grade applications. Oil-quench wear resistance with excellent machinability In practice it is supplied as hardened round bar for die making and as machined rotary die bodies, at 58-62 in normal production.