12C27 Steel

Description

12C27 is a stainless steel from Sandvik (Sweden), developed specifically for knife applications. Known for its very fine microstructure, excellent toughness, and good corrosion resistance. The steel is commonly used in pocket knives, kitchen knives, and outdoor knives.

Composition

Element	Content
Carbon (C)	0.60 %
Chromium (Cr)	13.5 %
Manganese (Mn)	0.4 %

Properties

Property	Value	Rating (1-10)
Hardness	58–60 HRC	—
Toughness	10–15 ft-lbs at 59 HRC	8/10
Corrosion Resistance	Good	8/10
Edge Retention (CATRA TCC)	~350–400 mm at 59 HRC	5/10
Carbide Volume	~6 % (chromium carbides)	—
Grindability	Very good	8/10

Microstructure

12C27 has a very fine microstructure with low carbide volume (~6 %). The chromium carbides are small and evenly distributed, resulting in good toughness and easy grindability.

Heat Treatment

Step	Temperature / Duration
Austenitizing	1050–1075 °C
Quench	Oil or air
Tempering	150–200 °C (2×)
Achievable Hardness	58–60 HRC

12C27M

12C27M is a modified version with reduced carbon content (0.55 %) for even better toughness at slightly lower hardness (57–59 HRC).

Steel	C	Hardness	Toughness	Corrosion	Edge Retention
12C27	0.60 %	59 HRC	8/10	8/10	5/10
12C27M	0.55 %	58 HRC	9/10	8/10	4/10
13C26 / AEB-L	0.68 %	60 HRC	8/10	7/10	5/10
14C28N	0.68 %	61 HRC	8/10	8/10	5/10

Pros and Cons

Pros:

Excellent toughness for a stainless steel
Very fine microstructure
Good corrosion resistance
Easy to grind and sharpen
Proven performance

Cons:

Limited maximum hardness
Moderate edge retention compared to higher-alloyed steels
Less available than other Sandvik steels

Conclusion

12C27 is an excellent stainless steel for applications that prioritize toughness and corrosion resistance. The fine microstructure enables good cutting performance with high reliability.

Sources

Knife Steel Nerds: 12C27 – Sandvik’s Fine-Grained Stainless Steel