S90V

Overview

CPM S90V is a specialist stainless steel built around edge retention.

It gets there through high vanadium content and powder metallurgy. The result is a steel that can keep cutting abrasive material for a long time, but asks for more patience when sharpening and more restraint in hard use.

S90V is not the steel for prying, chopping, or casual maintenance. It is the steel for people who know they want long edge life and have the tools to support it.

Composition and History

CPM S90V includes:

• Carbon (2.3%): High carbon content for hardness and carbide formation
• Chromium (14%): Provides stainless properties and chromium carbides
• Vanadium (9%): Creates extremely hard vanadium carbides for wear resistance
• Molybdenum (1%): Enhances hardenability and toughness
• Manganese (0.4%) and Silicon (0.4%): Aid in deoxidation and processing

The CPM process keeps the carbide structure finer and more even than conventional melting could manage at this alloy level. That does not make S90V tough; it makes this much carbide more usable in a knife.

Performance Tradeoffs

Edge Retention

S90V has excellent edge retention. In CATRA-style wear testing and real cardboard/rope use, it ranks near the top of practical stainless EDC options.

This is the reason to buy it. If your knife mostly slices abrasive material and you hate frequent sharpening, S90V makes sense.

Toughness

The tradeoff for S90V’s wear resistance is reduced toughness. It is much less forgiving than 3V, CruWear, 14C28N, or MagnaCut.

This means S90V is not recommended for:

• Heavy chopping or batoning
• Prying or twisting applications
• Knives subjected to lateral loads or impacts
• Hard use in cold environments

S90V belongs in cutting tasks where the blade sees mostly straight edge-on loads.

Corrosion Resistance

Despite 14% chromium content—well above the 10.5% minimum for stainless classification—S90V shows middle-of-the-road corrosion resistance. Testing reveals it performs adequately for most knife applications but falls short of ultra-corrosion-resistant steels like H1, LC200N, or even M390.

One common explanation is that a portion of chromium is tied up in carbides rather than remaining in solution for corrosion protection. In normal environments S90V is usually adequate, but marine or high-salt use may favor more corrosion-focused steels.

Ease of Sharpening

S90V is difficult to sharpen. The high volume of hard vanadium carbides changes the tool requirement:

• Standard aluminum oxide stones will struggle and wear quickly
• Diamond or CBN abrasives are essentially required
• Sharpening takes more time and effort compared to conventional steels
• Maintaining proper angles is critical due to the effort involved

Diamond or CBN is the practical baseline. If you do not own those abrasives, buy them before you buy an S90V knife.

Best Use Cases

S90V makes sense for:

• Edge retention is the main goal: users who make many cuts between sharpenings
• Cutting cardboard, rope, or abrasive materials: Industries where blades see continuous cutting duty
• Premium EDC folders: Enthusiasts willing to invest in performance and maintenance
• Specialist applications: Where the blade will see pure cutting tasks without lateral stress

Practical Buying Guidance

Pros:

• Industry-leading edge retention in a stainless steel
• Excellent wear resistance for extended cutting performance
• Adequate corrosion resistance for normal use
• Fine grain structure from CPM process reduces brittleness

Cons:

• Difficult to sharpen without diamond/CBN stones
• Lower toughness limits hard-use applications
• Premium pricing
• Requires strong maker execution and quality control
• Not ideal for cold environments or impact loads

When Not to Choose

• Not ideal for prying, twisting, or impact-heavy hard-use tasks where edge chipping risk is higher.
• Not a great choice if you want quick touch-ups on basic stones and low-effort sharpening.

Comparison Context

• Compare with S110V to see where each steel wins in practical EDC use.
• Compare with M390 to see where each steel wins in practical EDC use.
• Compare with S45VN to see where each steel wins in practical EDC use.

Continue Learning

• Read How to Choose Knife Steel by Use Case for a fast decision framework.
• Read CATRA Myths for Buyers to interpret edge-retention claims correctly.

Sources

• Knife Steel Nerds steel ratings reference
• Knife Steel Nerds metallurgy articles index