The Best Guide to Japanese Steel Types: Understanding Steels and Knives
Japanese steel is renowned for its exceptional quality and craftsmanship, especially in the field of knives. From ancient samurai swords to modern kitchen knives, Japan has a rich history of steelmaking. This guide will introduce you to the different types of Japanese steel, their properties, and recommended uses.
What is steel?
The basis of steel is iron enriched with carbon:
Iron + Carbon = Steel
The carbon content determines the classification:
- Iron: Contains 0 – 0.04% carbon
- Steel: Contains 0.04 – 2% carbon
Japanese steel is divided into two main categories:
- Carbon steel: Higher carbon content means greater hardness and sharpness, but greater susceptibility to corrosion.
- Stainless steel: Higher chromium content provides rust resistance.
Types of Japanese carbon steel
| Steel name | HRC (hardness) | Carbon % | Chromium % |
| Aogami Super | ~65 | 1.45 | - |
| Aogami #1 | ~64 | 1.3 | - |
| Aogami #2 | ~63 | 1.2 | - |
| Shirogami #1 | ~63 | 1.2 | - |
| Shirogami #2 | ~62 | 1.1 | - |
Aogami Series (Blue Steel)
- Aogami Super: Highest quality Japanese carbon steel, excellent sharpness and hardness, ideal for premium Santoku and Gyuto knives.
- Aogami #1: Enhanced with chromium and tungsten for greater durability and longer sharpness.
- Aogami #2: Popular among craftsmen for its ease of forging and high durability.
Shirogami Series (White Steel)
- Shirogami #1: Higher carbon content provides higher hardness and sharpness, requires a skilled craftsman.
- Shirogami #2: Traditional steel for Japanese knives, it excels in sharpness, hardness and easy sharpening.
Tamahagane (Tama steel)
Used for making samurai swords , known for its purity and high carbon content.
Types of Japanese stainless steel
| Steel name | HRC (hardness) | Carbon % | Chromium % |
| Gingham #3 | ~61 | 1.0 | 13 |
| VG10 | ~61 | 1.0 | 15 |
| AUS10 | ~61 | 0.95-1.1 | 13 |
| SPG2 powder | ~62 | 1.4 | 15 |
| R2 powder | ~62 | 1.4 | 15 |
| Molybdenum | ~58 | - | - |
| 440-A | ~54 | 0.6-0.75 | 17 |
Popular stainless steels
- Gingami #3: Combines the sharpness of carbon steel with corrosion resistance.
- VG10: Balanced steel with high hardness and corrosion resistance.
- SPG2 and R2: High-performance powder steels with high hardness and durability.
Conclusion
The quality of a Japanese knife is determined not only by the type of steel, but also by the correct heat treatment. Choosing the right knife will help you achieve the best results in the kitchen - whether you are a professional chef or a home cook.