What is "High Speed Steel" (HSS)?

High-speed steel (HSS) is a type of tool steel known for its ability to withstand high temperatures without losing its hardness. Composed mainly of carbon, chromium, tungsten, and molybdenum, HSS maintains its sharp edge and structural integrity even under intense heat generated by cutting or machining processes.

Japanese chef knives, renowned for their precision and sharpness, often utilize high-speed steel due to its exceptional hardness and durability.

HSS allows these knives to retain a razor-sharp edge for extended periods, reducing the need for frequent sharpening. Additionally, the steel's toughness makes it resistant to chipping and breaking, essential for the delicate and precise cutting techniques employed in Japanese cuisine.

The combination of hardness and resilience provided by high-speed steel ensures that Japanese chef knives deliver consistent performance and long-lasting sharpness, enhancing the efficiency and enjoyment of culinary tasks.

Steels with HSS properties

There are now modern Japanese knife steels like ATS-34 and Ginsan which are not high-speed steels but have been designed to take the best properties of HSS and are becoming widely used in Japanese knife making.

ATS-34:

  • ATS-34 is a high-carbon stainless steel known for its excellent edge retention and toughness.
  • Composed mainly of carbon, chromium, and molybdenum, it offers good corrosion resistance and can be hardened to a high degree, making it a favorite for high-end kitchen and tactical knives.

Ginsan (also known as Silver Steel No. 3 or Ginsanko):

  • Ginsan is a Japanese stainless steel that balances edge retention, corrosion resistance, and ease of sharpening.
  • It is composed mainly of carbon and chromium, providing good rust resistance while maintaining a fine grain structure for sharp edges.
  • Ginsan is often used in high-quality Japanese kitchen knives for its excellent cutting performance and durability.

Neither ATS-34 nor Ginsan are classified as high-speed steels, which are specifically designed for high-temperature applications and typically contain elements like tungsten and molybdenum to maintain hardness under heat.

Instead, ATS-34 and Ginsan are optimized for knife making, offering a balance of hardness, corrosion resistance, and edge retention suitable for kitchen use.