CPM 3V
CPM 3V is a powder-metallurgy tool steel from Crucible built for one job above all others: surviving hard impacts without chipping or breaking. It occupies what many knife metallurgists call a Goldilocks zone, delivering toughness closer to a dedicated shock-resistant steel like S7 while keeping wear resistance approaching D2. It is not stainless, but its 7.5% chromium content gives it noticeably better corrosion resistance than plain high-carbon steels.
CPM 3V FAQ
Is CPM 3V stainless?
No, but its 7.5% chromium content gives it noticeably better corrosion resistance than plain high-carbon tool steels. It still needs regular oiling and drying to prevent rust.
What hardness does CPM 3V reach?
Most hard-use knives run in the high 50s to low 60s Rc, favoring toughness over maximum hardness. See the heat treat details further down this page for the full recipe.
Is CPM 3V hard to sharpen?
No, it sharpens more easily than high-carbide tool steels like CPM M4 or D2. See the full grinding and sharpening guide.
How does CPM 3V compare to CPM CruWear or CPM M4?
CPM 3V is tougher than both, while CruWear closes much of the wear-resistance gap and CPM M4 offers substantially more edge retention at a real cost in toughness and ease of grinding. See the full breakdowns: CPM 3V vs CPM CruWear and CPM 3V vs CPM M4.
Also known as: CPM-3V, 3V
Composition
| Carbon (C) | 0.80% |
| Chromium (Cr) | 7.50% |
| Vanadium (V) | 2.75% |
| Molybdenum (Mo) | 1.30% |
Properties
| Property | Rating | Notes |
|---|---|---|
| Toughness | ★★★★★ | Exceptional. CPM 3V is widely regarded as one of the toughest knife steels available, significantly outperforming D2, CPM M4, and A2 in impact testing at comparable hardness. It is the standard reference point makers use when toughness is the top priority. |
| Edge Retention | ★★★☆☆ | Moderate. 3V does not hold an edge as well as high-vanadium stainless steels like S35VN or S30V, but it outperforms D2 in CATRA edge-retention testing at 60 HRC. Edge retention takes a back seat to toughness in this steel's design. |
| Corrosion Resistance | ★★☆☆☆ | 3V is not a stainless steel (chromium content is below the roughly 12-13% stainless threshold), so it will develop surface rust without care. Testing shows it resists deep pitting better than plain carbon steels even after prolonged exposure, but it still needs the same basic oiling and drying routine as any carbon tool steel. |
| Machinability / Grinding | ★★★☆☆ | Moderately demanding to grind due to fine, hard vanadium carbides, though less extreme than higher-vanadium stainless PM steels. Standard ceramic or zirconia belts handle it well. |
Heat Treatment
Crucible’s standard recipe: preheat 1500-1550 F, austenitize at 1950 F for 30-45 minutes, air or plate quench, then triple temper at 1000-1050 F for 2 hours each cycle. This targets 58-60 HRC, and the unusually high temper temperature is a secondary-hardening effect specific to this steel.
Many knifemakers instead use an alternative recipe that is simpler and popular in small shops: soak at 1975 F for 30 minutes, fast plate quench (optionally followed immediately by a cryo treatment), then triple 2-hour temper at 400 F. This reaches 60-61 HRC with no meaningful loss of toughness and avoids the need for a 1000 F+ capable oven cycle.
Best Uses
The go-to choice when a blade needs to survive real abuse without chipping or breaking: camp knives, choppers, survival and bushcraft blades, and any tool that might see batoning, prying, or hard impacts.
Sources: Crucible Industries, CPM 3V Data Sheet. Larrin Thomas, CPM-3V: Still the Best High Toughness Steel, Knife Steel Nerds, April 2025.