S35VN
Blade steels
S35VN Steel
Description
CPM-S35VN is a 2009-introduced evolution of S30V from Crucible Industries. Through reduced vanadium content (3 %) and 0.5 % niobium, S35VN offers improved toughness and machinability over S30V with slightly reduced edge retention. One of the most balanced PM steel combinations before the MagnaCut era.
Composition
| Element | Content |
|---|---|
| Carbon (C) | ~1.4 % |
| Chromium (Cr) | ~14 % |
| Molybdenum (Mo) | ~2 % |
| Vanadium (V) | 3.0 % (reduced vs. S30V) |
| Niobium (Nb) | 0.5 % |
| Nitrogen (N) | ~0.2 % |
Properties
| Property | Value | Rating (1-10) |
|---|---|---|
| Hardness | 58–62 HRC | — |
| Toughness | Better than S30V (finer carbides) | 7/10 |
| Corrosion Resistance | Good (similar to S30V) | 8/10 |
| Wear Resistance | High | 7/10 |
| Edge Retention | Good (slightly below S30V) | 7/10 |
| Machinability | Better than S30V | 6/10 |
| Grindability | Moderate | 5/10 |
Microstructure
The carbide structure of S35VN is finer than S30V due to the niobium addition. Niobium is a stronger carbide former than vanadium and leads to hard niobium carbides even in high-chromium steels. Small niobium additions improve toughness through microstructure refinement.
Heat Treatment
| Step | Temperature / Duration |
|---|---|
| Austenitizing | 1040–1095 °C (2000 °F recommended) |
| Quench | Oil |
| Cryo | Optional (improves hardness) |
| Tempering | 175–230 °C (400 °F recommended, 2×) |
| Achievable Hardness | 58–62 HRC |
Optimal combination: 2000 °F austenitizing + cryo + 400 °F tempering → 61–62 HRC with good toughness.
Comparison with Related Steels
| Steel | Wear Resistance | Toughness | Corrosion | Edge Retention |
|---|---|---|---|---|
| S35VN | 7/10 | 7/10 | 8/10 | 7/10 |
| S30V | 8/10 | 5/10 | 8/10 | 8/10 |
| S45VN | 7/10 | 6/10 | 9/10 | 7/10 |
| M390 | 9/10 | 4/10 | 9/10 | 9/10 |
| MagnaCut | 8/10 | 8/10 | 9/10 | 8/10 |
Pros and Cons
Pros:
- Better toughness than S30V due to niobium addition
- Finer carbide structure
- Good corrosion resistance (similar to S30V)
- Better machinability than S30V
- Balanced property profile
Cons:
- Slightly lower edge retention than S30V
- Not as corrosion resistant as M390 or S45VN
- PM process → higher cost than conventional steels
Conclusion
S35VN offers an excellent balance between toughness, edge retention, and corrosion resistance. As an improved version of S30V with niobium addition, it is one of the most balanced PM steel combinations before the MagnaCut era. Suitable for pocket knives, hunting knives, kitchen knives, and general EDC knives.