It is a high-carbon tool steel, specially developed and cast by the Hitachi steel mill for durable knives and tools. It is characterized by a very high level of purity (sulfur and phosphorus content below 0.03%), which makes it one of the highest quality steel. It differs from typical carbon steels by its outstanding hardness - which can even exceed 63 HRC. This hardness is obtained by a significant addition of carbide-forming elements such as chromium and tungsten. This steel has all the advantages of carbon steels, apart from hardness, it is extremely easy to sharpen and keeps sharpness for a long time. These features guarantee a very pleasant, silky, but also aggressive cut. However, be careful, the unusual hardness can reduce its resistance to cracking and chipping. Knives made of this type of steel due to the fact that they are rust, become covered with a patina with time, which not everyone considers aesthetic. However, it is useful because it blocks the further progress of corrosion by creating a protective layer.
Composition:
- Carbon: 1,05-1,15%
- Tungsten: 1,00-1,50%
- Chromium: 0,20-0,50%
- Manganese: 0,20-0,30%
- Silicon: 0,10-0,20%
- Phosphorus: 0,025%
- Sulfur: 0,004%