Crucible Industries / USA

CPM-4V

High Toughness Tool Steel (Non-Stainless)58–64 HRCCrucible Particle Metallurgy (CPM)

Composition

Core alloying elements define the baseline trade-off between wear resistance, corrosion behavior, and toughness.

Material Overview

CPM 4V is a high-performance powder metallurgy tool steel developed by Crucible Industries, optimized specifically for toughness and impact resistance. It features a refined CPM microstructure that significantly improves durability compared to conventional tool steels. While its edge retention is good, it is not its strongest feature; instead, it excels in resisting chipping, breaking, and deformation under extreme stress. It is widely regarded as one of the best steels for hard-use survival and outdoor applications where reliability is critical.

Performance Radar

Use four core metrics to understand the usable operating envelope of this steel at a glance.

Edge Retention

Toughness

Corrosion Resistance

Sharpenability

Edge Retention

7.0

Toughness

10.0

Corrosion Resistance

3.0

Sharpenability

8.0

Advantages

Exceptional toughness (industry-leading)
Very high impact resistance
Good wear resistance for its toughness level
CPM structure improves consistency
Excellent for hard-use outdoor knives

Disadvantages

Low corrosion resistance (non-stainless)
Moderate edge retention compared to wear-focused steels
Requires maintenance to prevent rust
Not ideal for fine slicing-focused knives

At A Glance

CPM 4V is an ultra-tough powder metallurgy tool steel designed for extreme impact resistance and durability, making it one of the best choices for heavy-use and hard-impact knives.