CPM S30V
CPM S30V was developed by Crucible Industries with knifemaker Chris Reeve specifically for the cutlery market, and it became the benchmark premium stainless steel for over a decade. Its vanadium-rich chemistry and fine powder-metallurgy grain give it exceptional edge retention, though it can run tougher to grind and slightly less tough than the newer steels it inspired, like S35VN.
CPM S30V FAQ
What hardness does CPM S30V reach?
Most knives run in the low-to-mid 60s Rc. See the heat treat details further down this page for the full recipe.
Is CPM S30V hard to sharpen?
Yes, it is one of the more demanding steels in this database to sharpen due to its heavy vanadium carbide content. It can be sharpened effectively on the belt grinder itself with soft-backed belts and a felt polishing wheel, or off the machine with diamond abrasives. See the full grinding and sharpening guide.
Does CPM S30V rust?
It offers good, dependable stainless corrosion resistance from its 14% chromium content, suitable for everyday-carry and outdoor use.
How does CPM S30V compare to CPM S35VN or CPM 20CV?
S30V holds a slight edge-retention advantage over S35VN but is tougher to grind, and offers slightly less corrosion resistance than CPM 20CV at essentially tied edge retention. See the full breakdowns: CPM S30V vs CPM S35VN and CPM 20CV vs CPM S30V.
Also known as: CPM S30V, S30V
Composition
| Carbon (C) | 1.45% |
| Chromium (Cr) | 14.00% |
| Vanadium (V) | 4.00% |
| Molybdenum (Mo) | 2.00% |
Properties
| Property | Rating | Notes |
|---|---|---|
| Toughness | ★★★☆☆ | The weakest point of an otherwise excellent steel; a heavier vanadium carbide load than S35VN makes it more prone to chipping, which is the main reason Crucible developed S35VN as a tougher successor. |
| Edge Retention | ★★★★★ | Rated around 149% CATRA edge retention versus 440C, among the best in its class and the main reason it remained the benchmark premium stainless steel for years. |
| Corrosion Resistance | ★★★★☆ | Good stainless performance from 14% chromium, comparable to S35VN and suitable for everyday-carry and outdoor use. |
| Machinability / Grinding | ★★☆☆☆ | Notably harder to grind than S35VN due to its higher vanadium carbide content; expect faster belt wear and slower stock removal. |
Heat Treatment
Austenitize at 1900-2000 F for 15-30 minutes, then quench with air or positive pressure quench (or an interrupted oil/salt quench) to below 125 F. A cryogenic treatment is commonly added for maximum properties. Double temper at 400-750 F, holding at least 2 hours per cycle: temperatures near 400 F favor maximum edge retention and hardness, while higher temper temperatures trade some hardness for improved toughness. Most knife applications land in the low-to-mid 60s Rc.
Best Uses
The steel behind many legendary premium production folders, still a strong choice for EDC knives where long edge retention is the top priority. Browse more entries in the Knife Steel Database, and see the Heat Treating Guide for the full stage-by-stage process.
Sources: Crucible Industries CPM S30V datasheet; Larrin Thomas, S35VN Steel: Properties and How to Heat Treat, Knife Steel Nerds (comparative data).