An Independent Guide
CPM S90V Steel Review
When discussing the world’s best premium knife steels, CPM S90V is almost always part of the conversation. Developed for exceptional edge retention and wear resistance, S90V has become a favorite among knife enthusiasts, collectors, and professionals who demand maximum cutting performance from their blades.
Unlike many conventional stainless steels, CPM S90V is produced using Crucible Particle Metallurgy (CPM), a manufacturing process that creates an exceptionally fine and uniform microstructure. This allows the steel to achieve remarkable hardness while maintaining excellent corrosion resistance and edge stability.
But is CPM S90V really worth its premium price? Is it better than M390 or MagnaCut? How difficult is it to sharpen? And is it suitable for everyday use?
In this comprehensive review, we’ll explore everything you need to know about CPM S90V, from its chemical composition and heat treatment to real-world performance and comparisons with other high-end knife steels.
What Is CPM S90V Steel?
CPM S90V is a premium stainless powder metallurgy steel developed in the United States. It was specifically engineered to provide outstanding wear resistance and exceptional edge retention without sacrificing corrosion resistance.
Originally introduced for industrial cutting applications, S90V quickly gained popularity among custom knifemakers and premium production brands. Its unique alloy composition, particularly its very high vanadium content, gives it wear resistance far beyond most traditional stainless steels.
Today, CPM S90V is commonly found in high-end folding knives, hunting knives, outdoor knives, and premium everyday carry (EDC) knives. While it occasionally appears in kitchen knives, it is far more common in outdoor and utility blades because of its impressive durability and ability to hold a sharp edge for extended periods.
What Does “CPM” Mean?
The letters CPM stand for Crucible Particle Metallurgy, an advanced manufacturing process that differs significantly from conventional steel production.
Instead of pouring molten steel into large ingots, the molten alloy is atomized into microscopic powder particles. These particles are then compressed under high pressure and heat to create solid steel billets.
This process offers several important advantages:
- Extremely fine grain structure
- Uniform carbide distribution
- Improved wear resistance
- Better edge stability
- Increased consistency from batch to batch
Powder metallurgy allows S90V to contain much larger amounts of hard carbides than would be practical in conventional steels, giving it its famous cutting longevity.
CPM S90V Chemical Composition
Although exact compositions vary slightly between production batches, CPM S90V typically contains:
| Element | Approximate Content |
|---|---|
| Carbon | 2.30% |
| Chromium | 14.0% |
| Vanadium | 9.0% |
| Molybdenum | 1.0% |
This alloy composition makes S90V one of the most wear-resistant stainless knife steels available.
Let’s examine what each element contributes.
Carbon
With approximately 2.3% carbon, S90V contains significantly more carbon than most premium knife steels.
Carbon increases:
- Hardness
- Edge retention
- Wear resistance
- Strength
High carbon content also enables the formation of large quantities of extremely hard carbides.
Chromium
Chromium serves two primary functions.
First, it provides excellent corrosion resistance, making S90V a true stainless steel.
Second, chromium contributes to carbide formation, improving wear resistance while helping the blade resist staining and rust.
With roughly 14% chromium, S90V performs well in humid environments and requires far less maintenance than high-carbon tool steels.
Vanadium
Vanadium is the defining element in CPM S90V.
Containing approximately 9% vanadium, S90V has one of the highest vanadium contents found in commercially available knife steels.
Vanadium forms incredibly hard carbides that dramatically improve:
- Edge retention
- Abrasion resistance
- Edge stability
- Fine grain structure
These carbides are largely responsible for S90V’s legendary ability to stay sharp.
Molybdenum
Molybdenum improves:
- Corrosion resistance
- Hardenability
- Strength
- High-temperature stability
Although present in smaller amounts than vanadium, molybdenum contributes to the steel’s overall balance.
CPM S90V Hardness
Most manufacturers heat treat CPM S90V to between 59 and 61 HRC, although premium makers often target 60–62 HRC.
Some custom knifemakers may push hardness slightly higher, but doing so generally reduces toughness.
At these hardness levels, S90V delivers exceptional edge stability while remaining suitable for demanding cutting applications.
Edge Retention
Edge retention is the area where CPM S90V truly excels.
Many knife enthusiasts consider S90V one of the very best steels available for maintaining a sharp edge through prolonged use.
Its extremely high volume of vanadium carbides provides outstanding resistance to abrasive wear. As a result, S90V can continue cutting efficiently long after many other premium steels have begun to lose their sharpness.
For users who dislike frequent sharpening, this is one of S90V’s greatest advantages.
Hunters, outdoorsmen, and professionals who rely on their knives throughout the day often appreciate the extended cutting performance that S90V offers.
Cutting Performance
Despite its emphasis on wear resistance, S90V remains an excellent cutting steel.
A properly heat-treated blade can support a thin, stable edge capable of slicing cleanly through a wide range of materials.
Common cutting tasks include:
- Cardboard
- Rope
- Plastic
- Leather
- Food preparation
- Wood carving
- General utility work
Because the edge resists wear so effectively, cutting performance remains consistent for an unusually long time.
| Steel | Corrosion |
|---|---|
| S90V ⭐⭐⭐⭐⭐ | |
| MagnaCut ⭐⭐⭐⭐⭐ | |
| M390 ⭐⭐⭐⭐⭐ | |
| Vanax ⭐⭐⭐⭐⭐ | |
| CruWear ⭐⭐⭐ |
Corrosion Resistance
Although S90V is primarily known for wear resistance, its corrosion resistance is also impressive.
The combination of approximately 14% chromium and powder metallurgy manufacturing helps the steel resist:
- Rust
- Staining
- Humidity
- Sweat
- Light exposure to saltwater
- Acidic foods
While no stainless steel is completely immune to corrosion, S90V performs exceptionally well with normal maintenance.
Simply cleaning and drying the blade after use is generally sufficient.
Toughness
Every knife steel involves trade-offs.
In exchange for its remarkable wear resistance, CPM S90V sacrifices some toughness.
Compared to steels such as MagnaCut, CPM 3V, or AEB-L, S90V is more susceptible to chipping if subjected to heavy impacts or abusive use.
It is not designed for:
- Batoning hardwood
- Chopping through bone
- Prying
- Striking hard materials
- Cutting frozen food
Instead, S90V performs best in precision cutting applications where its superior edge retention can shine.
Wear Resistance
Few stainless steels can match CPM S90V’s wear resistance.
The steel’s high concentration of vanadium carbides makes it extremely resistant to abrasive materials.
This is particularly beneficial when cutting:
- Cardboard
- Fibrous rope
- Carpet
- Packaging materials
- Synthetic fabrics
- Dense plastics
Many users report that S90V maintains useful sharpness several times longer than conventional stainless steels such as 440C or AUS-8.
Is CPM S90V Easy to Sharpen?
One of the most common questions is whether S90V is difficult to sharpen.
The honest answer is yes—but not impossible.
Because of its extremely hard vanadium carbides, S90V requires more time and higher-quality abrasives than many other steels.
Diamond stones and premium ceramic stones generally produce the best results.
Fortunately, the trade-off is that sharpening is needed much less frequently.
Many users find they spend less total time sharpening over the life of the knife compared with steels that dull more quickly.
Does S90V Take a Sharp Edge?
Absolutely.
Although it may require more effort to sharpen, CPM S90V is capable of achieving an extremely refined cutting edge.
Proper sharpening can produce:
- Hair-shaving sharpness
- Clean push cuts
- Excellent slicing performance
- Fine edge stability
The steel’s fine powder metallurgy structure supports consistent sharpening despite its high wear resistance.
Best Uses for CPM S90V
S90V is particularly well suited to knives that are expected to cut for extended periods without maintenance.
Ideal applications include:
- Everyday carry (EDC)
- Folding knives
- Hunting knives
- Skinning knives
- Utility knives
- Outdoor knives
- Premium pocket knives
It is especially popular among users who value long-lasting sharpness over maximum toughness.
Applications Where S90V Is Less Suitable
Although S90V is an exceptional cutting steel, it is not the perfect choice for every task.
You may prefer a tougher steel if you frequently:
- Chop hardwood
- Baton firewood
- Pry objects apart
- Strike bone
- Perform heavy survival tasks
For these demanding applications, steels such as CPM 3V or MagnaCut may be more forgiving.
CPM S90V vs M390
CPM S90V and M390 are often compared because both are premium stainless powder metallurgy steels.
| Feature | CPM S90V | M390 |
|---|---|---|
| Edge retention | Excellent | Excellent |
| Wear resistance | Higher | Very High |
| Corrosion resistance | Excellent | Excellent |
| Toughness | Moderate | Slightly Better |
| Sharpening | More difficult | Easier |
S90V generally provides slightly longer edge life, while M390 offers a more balanced combination of wear resistance and toughness.
Check Our Guide M390 Steel Review
CPM S90V vs MagnaCut
MagnaCut has quickly become one of the most talked-about knife steels thanks to its outstanding balance of properties.
Compared to S90V:
S90V offers:
- Longer edge retention
- Higher wear resistance
- Excellent slicing longevity
MagnaCut offers:
- Much greater toughness
- Easier sharpening
- Better resistance to chipping
- Similar corrosion resistance
Users who prioritize maximum cutting endurance often prefer S90V, while those seeking an all-around performer frequently choose MagnaCut.
Check Our Guide MagnaCut Steel Review
CPM S90V vs CPM S110V
Because their names are similar, many buyers assume CPM S90V and CPM S110V perform almost identically. In reality, each steel was designed with a different balance of properties.
CPM S110V contains even higher levels of alloying elements, including vanadium and niobium, giving it exceptional wear resistance and corrosion resistance. In laboratory testing, S110V can outlast S90V in edge retention, but the improvement is smaller than many people expect.
| Feature | CPM S90V | CPM S110V |
|---|---|---|
| Edge Retention | ★★★★★ | ★★★★★+ |
| Toughness | Better | Lower |
| Corrosion Resistance | Excellent | Outstanding |
| Sharpening | Difficult | Very Difficult |
For most users, S90V is the more practical choice because it offers easier sharpening and slightly better toughness while still providing phenomenal edge retention.
CPM S90V vs Elmax
Both steels are premium powder metallurgy stainless steels, but they emphasize different strengths.
CPM S90V
- Longer edge retention
- Higher wear resistance
- Better for extended cutting sessions
Elmax
- Better toughness
- Easier sharpening
- Excellent corrosion resistance
- More forgiving during heavy use
If you primarily cut abrasive materials such as cardboard, rope, or heavy packaging, S90V has the advantage. If you want one knife that can perform both everyday cutting and occasional outdoor work, Elmax is often the more balanced option.
Check Our Guide ELMAX Steel Review
CPM S90V vs CPM 20CV
CPM 20CV, M390, and CTS-204P are often considered equivalent steels.
Compared with CPM 20CV:
S90V offers
- Better wear resistance
- Longer edge retention
20CV offers
- Easier sharpening
- Slightly better toughness
- More balanced overall performance
For many users, the decision comes down to whether maximum edge retention or easier maintenance is more important.
CPM S90V vs SG2
Although both are powder metallurgy steels, they were developed for different purposes.
SG2 is primarily used in premium Japanese kitchen knives, where a thin edge and precise slicing are essential.
CPM S90V is more common in folding knives, hunting knives, and premium EDC blades.
SG2 excels in:
- Kitchen performance
- Fine slicing
- Food preparation
- Thin blade geometry
S90V excels in:
- Outdoor use
- Everyday carry
- Utility cutting
- Extremely long edge life
Neither steel is objectively better—they simply serve different roles.
Check Our Guide SG2 Steel Review
CPM S90V vs Vanax
Vanax is one of the most corrosion-resistant knife steels ever produced.
Compared with S90V:
Vanax provides:
- Outstanding corrosion resistance
- Better toughness
- Easier maintenance in marine environments
S90V provides:
- Higher wear resistance
- Longer cutting life
- Better performance when cutting abrasive materials
For saltwater fishing, diving, or humid tropical climates, Vanax is difficult to beat. For general EDC and utility use, S90V remains one of the strongest performers.
CPM S90V vs CruWear
CruWear is a tool steel rather than a stainless steel.
Compared with CPM S90V:
S90V
- Stainless
- Better edge retention
- Better corrosion resistance
CruWear
- Much tougher
- Easier sharpening
- Better for heavy outdoor use
CruWear is an excellent choice for hard-use fixed blades, while S90V is optimized for long-lasting cutting performance.
Real-World Performance
Laboratory testing provides valuable information, but daily use tells the full story.
Cardboard
Cardboard is surprisingly abrasive due to adhesives and embedded fibers.
S90V excels in this environment.
Warehouse workers, delivery drivers, and tradespeople often report weeks of daily cutting before noticeable dulling occurs.
Rope
Synthetic rope contains abrasive fibers that rapidly wear many knife steels.
S90V’s high vanadium carbide content allows it to continue slicing cleanly even after extensive rope cutting.
Leather
Leatherworkers appreciate S90V because it produces consistent, clean cuts without requiring frequent touch-ups.
Plastic
Heavy plastic packaging quickly dulls softer steels.
S90V maintains its edge remarkably well, making it an excellent option for warehouse and industrial work.
Food Preparation
Although designed primarily for utility knives, S90V performs well in the kitchen.
It easily slices:
- Meat
- Fruit
- Vegetables
- Cheese
- Bread (with an appropriate blade geometry)
However, many chefs still prefer steels such as SG2 or AEB-L because they sharpen more easily and support thinner kitchen-specific grinds.
Heat Treatment Matters
Steel composition is only one part of knife performance.
A well-executed heat treatment determines:
- Final hardness
- Toughness
- Edge stability
- Corrosion resistance
- Ease of sharpening
Two knives made from CPM S90V can perform noticeably differently if they are heat treated by different manufacturers.
For this reason, the reputation of the knife maker is just as important as the steel itself.
Check Our Guide Steel Heat Treatment Explained
Sharpening Guide
Because S90V contains an exceptionally high volume of vanadium carbides, choosing the right sharpening equipment is important.
Recommended Stones
For routine maintenance, many enthusiasts prefer:
- Diamond plates
- Diamond water stones
- Premium ceramic stones
Traditional aluminum oxide stones can sharpen S90V, but the process is generally slower.
Sharpening Angles
Most folding knives perform well between:
17–20 degrees per side
Outdoor knives may benefit from a slightly wider angle for improved durability.
Burr Removal
One of the biggest mistakes when sharpening S90V is leaving a large burr attached to the edge.
Use progressively lighter strokes and finish with alternating passes until the burr disappears.
Stropping
Leather strops loaded with fine diamond compound work particularly well with S90V.
Occasional stropping can restore cutting performance between full sharpening sessions.
Maintenance Tips
Although S90V is stainless, proper maintenance still extends the life of the knife.
Recommended care:
- Hand clean after use.
- Dry thoroughly.
- Keep the pivot clean on folding knives.
- Apply light lubricant if storing long-term.
- Avoid prolonged exposure to saltwater.
Simple maintenance helps preserve both appearance and cutting performance.
Check Our Guide Best Hunting Knife Features Explained
| Steel | Edge | Toughness | Corrosion | Sharpening |
|---|---|---|---|---|
| S90V | ⭐⭐⭐⭐⭐ | ⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐ |
| MagnaCut | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐ |
| M390 | ⭐⭐⭐⭐ | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐ |
| Elmax | ⭐⭐⭐⭐ | ⭐⭐⭐⭐ | ⭐⭐⭐⭐ | ⭐⭐⭐⭐ |
| S110V | ⭐⭐⭐⭐⭐ | ⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐ |
Common Myths About CPM S90V
Myth 1: S90V Never Needs Sharpening
No steel remains sharp forever.
Although S90V lasts much longer than most steels, eventually every edge requires maintenance.
Myth 2: S90V Is Impossible to Sharpen
Modern diamond abrasives have made sharpening S90V much easier than it once was.
While it takes longer than VG10 or 14C28N, experienced sharpeners can achieve excellent results.
Myth 3: More Vanadium Always Means Better Steel
Higher vanadium increases wear resistance, but it also makes sharpening more difficult and can reduce toughness.
Knife steel selection always involves trade-offs.
Myth 4: S90V Is Too Brittle for Everyday Carry
When properly heat treated and used appropriately, S90V performs very well as an everyday carry steel.
Most edge damage results from misuse rather than normal cutting.
Buying Guide
Before purchasing an S90V knife, consider the following:
Blade Geometry
A well-ground blade often outperforms a thicker blade made from a more expensive steel.
Heat Treatment
Buy from manufacturers with strong reputations for consistent heat treatment.
Intended Use
Choose S90V if your priority is:
- Edge retention
- Everyday cutting
- Utility work
- Hunting
Consider tougher steels if your knife will experience heavy impacts.
Frequently Asked Questions
Is CPM S90V stainless?
Yes. With approximately 14% chromium, CPM S90V is considered a true stainless steel and offers excellent corrosion resistance.
What hardness is CPM S90V?
Most manufacturers heat treat S90V between 59 and 61 HRC, while some premium makers target 60–62 HRC.
Is S90V better than M390?
For maximum edge retention, many users prefer S90V. For a more balanced combination of toughness, corrosion resistance, and sharpening ease, M390 is often considered the better all-around choice.
Is S90V better than MagnaCut?
It depends on your priorities. S90V offers longer edge life, while MagnaCut provides significantly greater toughness and easier sharpening.
Does CPM S90V rust?
Under normal conditions, S90V is highly resistant to rust. Basic cleaning and drying are generally sufficient for everyday use.
Is S90V good for hunting knives?
Yes. Its excellent edge retention makes it a favorite among hunters who process multiple animals without frequent sharpening.
Is S90V suitable for beginners?
Yes, although beginners should be aware that sharpening takes more time than with simpler steels.
Can S90V chip?
Like many high-hardness steels, S90V can chip if used improperly for prying, chopping, or cutting hard materials such as bone or metal.
Is S90V good for kitchen knives?
It performs well, but it is more commonly used in EDC and outdoor knives. Kitchen-focused steels such as SG2 or AEB-L are often preferred for dedicated culinary use.
How long does S90V stay sharp?
Depending on use, S90V can remain sharp significantly longer than most premium stainless steels, making it one of the best choices for users who value long intervals between sharpening.
Final Verdict
CPM S90V has earned its reputation as one of the finest high-end knife steels available. Its combination of exceptional edge retention, outstanding wear resistance, excellent corrosion resistance, and premium powder metallurgy construction makes it an outstanding choice for users who demand maximum cutting performance.
Its primary compromise is reduced toughness compared to newer balanced steels such as MagnaCut or tool steels like CPM CruWear. Sharpening also requires more time and better abrasives than simpler stainless steels. However, because S90V stays sharp for so long, many owners find these trade-offs well worth it.
Whether you’re looking for a premium everyday carry knife, a reliable hunting companion, or a high-performance utility blade, CPM S90V continues to stand among the elite. Decades after its introduction, it remains a benchmark for wear-resistant stainless steels and a favorite among knife enthusiasts who prioritize long-lasting sharpness above all else.
CPM S90V
★★★★★ Edge Retention
★★★★★ Wear Resistance
★★★★★ Corrosion Resistance
★★★ Toughness
★★ Sharpening Ease
This article is for independent informational purposes only and is not affiliated with, sponsored by, or endorsed by any steel manufacturer. All product names, trademarks, and registered trademarks are the property of their respective owners.