Steel Material使用鋼材
At Azuma Minamoto no Masahisa, the performance of a knife is determined not only by the type of steel selected, but also by the forging and heat-treatment processes applied to it. Even when the same steel is used, adjustments during forging and quenching allow control over hardness, toughness, and overall cutting performance.
Below is a detailed explanation of the steels used in our knives.
Carbon Steels (Reactive/Rust-Prone)
Carbon steel—commonly referred to as “hagane”—is known for its exceptional sharpness, strong edge retention, and ease of sharpening. For this reason, it is widely used in professional kitchens. However, carbon steel is susceptible to rust and may discolor due to moisture or due the acidity of ingredients. Regular and attentive maintenance is therefore essential.
White Steel No.2 (Shirogami #2)
White Steel No.2 is a highly pure carbon steel in which impurities such as phosphorus (P), sulfur (S), and manganese (Mn) are minimized through extensive processing It serves as the standard reference for both White and Blue steel series.
Characteristics:
- Excellent blade hardness (sharpness)
- Strong wear resistance (edge longevity)
- Ease of sharpening
- Well-balanced overall performance
Because of its balance between sharpness and workability, White Steel No.2 is widely used in traditional Japanese knives. It is also recommended as an entry point into authentic carbon steel knives.
Manufacturer: Hitachi Yasugi Steel
※At our shop, we use White Steel No.2 and White Steel No.1 with impurities reduced as much as possible to ensure high quality.
White Steel No.1 (Shirogami #1)
White Steel No.1 is similarly a highly pure carbon steel with further minimized impurities. Compared to White Steel No.2, it features higher carbon content and purity.
Characteristics:
- Superior blade hardness
- Strong wear resistance
- Ease of sharpening
- Balanced performance
It is widely used across traditional Japanese knives and is suitable for those seeking the performance of high-grade carbon steel.
Manufacturer: Hitachi Yasugi Steel
Blue Steel No.2 (Aogami #2)
Blue Steel No.2 is based on pure White steel with the addition of tungsten (W) and chromium (Cr), improving heat-treatment characteristics and wear resistance.
Characteristics:
- Increased hardness through high-temperature quenching
- Improved resistance to softening during tempering
- Enhanced wear resistance
- Improved corrosion resistance compared to pure carbon steel
Due to its excellent edge retention, it is favored by users who work for extended periods or sharpen less frequently.
Manufacturer: Hitachi Yasugi Steel
Blue Steel No.1 (Aogami #1)
Blue Steel No.1 is based on White steel with added tungsten and chromium, similar to Blue Steel No.2, but with higher carbon content and purity.
Characteristics:
- Higher blade hardness (sharpness)
- Enhanced wear resistance (long edge life)
- Suitable for applications requiring refined technique
This steel is valued in professional environments where precision and sustained performance are essential.
Manufacturer: Hitachi Yasugi Steel
Japanese Steel (SK5)
Japanese Steel (SK5) is a carbon steel with reduced impurities. While its purity is lower than that of White steel, it is more affordable and less prone to chipping.
Characteristics:
- Good sharpness typical of carbon steel
- Ease of sharpening
- Greater resistance to chipping
- Suitable for processing facilities and home use
Manufacturer: Hitachi
Original Carbon
This steel contains a higher carbon content along with chromium (Cr).
Characteristics:
- High hardness
- Sharp cutting performance
- Slightly more corrosion resistant than pure carbon steel
- Ease of sharpening and handling
It offers balanced and versatile performance and is recommended for those using carbon steel knives for the first time.
Manufacturer: Hitachi
VG1 (V-Gold No.1)
VG1 is a carbon alloy steel enhanced with additoonal chromium (Cr) and molybdenum (Mo), offering improved corrosion resistance compared to pure carbon steel while retaining exceptional sharpness with easier manitainece.
Characteristics:
- Improved resistance to rust
- Strong wear resistance (edge retention)
- Reduced sticking when cutting fatty ingredients
It is commonly used in meat and fish processing environments where large volumes of ingredients are handled.
Manufacturer: Takefu Special Steel
Stainless Steels (Corrosion-Resistant)
Stainless steels are widely used due to their resistance to rust and relatively low maintenance requirements. They are suitable for home kitchens, professional restaurants, and processing facilities alike. However, stainless steel is not completely immune to corrosion. Prolonged exposure to moisture, salt, acidic substances, or contact with other metals may still cause rust.Proper care remains important.
Silver Steel No.3 (Ginsan / Ginsanko)
Silver Steel No.3 contains a higher chromium content than carbon steel and is widely used for traditional Japanese knives.
The balance of carbon, chromium (Cr), and molybdenum (Mo) makes it particularly suitable for knife production within the Silver series.
Characteristics:
- Sharpness close to pure carbon steel
- Easier sharpening compared to many stainless steels
- Well-balanced composition and stable steel
- Widely used by professional chefs
- Suitable for handling acidic ingredients
While not entirely rust-proof, it offers strong corrosion resistance compared to a pure carbon steel knife.
Manufacturer:Hitachi Yasugi Steel
VG10 (V-Gold No.10)
VG10 contains high levels of carbon and chromium (Cr), as well as cobalt (Co), which prevents decarburization during heat treatment.
Characteristics:
- Very high hardness
- Excellent grindability
- Long edge retention
- Slightly more difficult to sharpen
- Regarded as one of the highest-grade corrosion-resistant stainless knife steels
It is one of the most popular steels for both Japanese and Western knife makers and is widely used by professionals and home cooks alike.
Manufacturer:Takefu Special Steel
VG5 (V Gold No.5) Stainless Steel
VG5 is a high-quality stainless steel developed as a close sibling to VG10. It offers similar sharpness, edge retention, and corrosion resistance, but with slightly lower hardness, making it easier to sharpen and maintain. This makes VG5 a practical and user-friendly steel for both professional chefs and home cooks.
Characteristics:
- Excellent sharpness
- Good edge retention
- High rust resistance
- Easier to sharpen than VG10
- Well-balanced and reliable for everyday use
Manufacturer:Takefu Special Steel
AUS-8
AUS-8 incorporates molybdenum to optimize carbide distribution and strengthen the steel matrix, delivering a balanced profile of sharpness, toughness, and stain resistance.
Characteristics:
- Relatively affordable
- Good sharpness
- Easy sharpening
- Ease of handling
Used in professional kitchens, processing facilities, and home environments.
Manufacturer:Aichi Steel
AUS-10
AUS-10 includes molybdenum (Mo) and a higher carbon percentage than AUS-8, enabling it to reach higher hardness. This translates to sharper edges and better edge retention, while still maintaining good corrosion resistance.
Characteristics:
- Improved sharpness retention
- Affordable
- Easy sharpening
- Easy handling
Manufacturer:Aichi Steel
Molybdenum Steel (Mo)
Molybdenum steel is a stainless alloy containing molybdenum (Mo), which enhances corrosion resistance, hardenability, and overall durability. It is widely used in commercially available kitchen knives due to its balanced performance and ease of maintenance.
Characteristics:
- Affordable
- Good sharpness
- Easy sharpening
- Ease of handling
Used broadly in both professional and home kitchens.
Manufacturer:Aichi Steel
High-Speed Steel (Powdered HSS)
High-Speed Steel (Powdered HSS) is a stainless-based alloy containing chromium (Cr), tungsten (W), molybdenum (Mo), and vanadium (V), designed for exceptional hardness, wear resistance, and edge retention.
Characteristics:
- Dense and uniform metal structure
- High toughness
- Excellent wear resistance
- Sharp cutting performance
- Long-lasting edge once sharpened
- More difficult to sharpen
It is suitable for professionals as well as home users seeking long-term performance with minimal maintenance.
Manufacturer:Hitachi HSS
Zui (Original Special Stainless Steel)
Among various Swedish steels, ZUI is developed using select high-purity Swedish steel known for its low impurity levels and refined carbon matrix. Through controlled heat treatment and additional refinement, the steel achieves elevated hardness while maintaining structural toughness and resistance to micro-chipping.
Used exclusively for Western-style knives.
Characteristics:
- Very thin blade geometry
- Smooth penetration into ingredients
- Suitable for delicate tasks
- Effective for tomatoes, sushi rolls, and fragile foods