Japanese Knife Steel Guide

Japanese knife steel is not one ladder from “bad” to “best.” Different steels balance corrosion resistance, hardness, toughness, edge retention and ease of sharpening differently, and the maker's heat treatment and blade geometry matter as much as the steel name printed on a product page.

This guide explains the steels currently relevant to our Japanese knife assortment.

Start with the main choice: stainless, semi-stainless or carbon

Stainless steel resists corrosion better and is generally easier for everyday care. Carbon steel is more reactive, can develop patina and needs prompt washing and drying. Semi-stainless steels sit between those broad categories and still deserve sensible care.

These categories are not quality grades. Excellent and mediocre knives can exist in each.

VG10

VG10 is a stainless cutlery steel widely used in Japanese kitchen knives. In a well-made knife it can provide a useful combination of corrosion resistance, hardness and edge retention for everyday use. Exact performance depends on heat treatment and geometry.

Our assortment includes VG10-core knives with stainless cladding as well as layered Damascus constructions built around a VG10 core.

Aogami / Blue Paper steel

Aogami is a family of Japanese carbon steels often called Blue Paper steel. Aogami #2 is used in several knives in our current range. It is reactive and should be washed and dried promptly. It can take a fine edge and is popular with makers who want high-carbon performance, but it should not be described as automatically “better” than stainless steel.

Shirogami / White Paper steel

Shirogami is another Japanese carbon-steel family, commonly called White Paper steel. Shirogami #2 appears in some traditional knives in our range. It is reactive, can develop patina and needs corrosion care. It is often valued for straightforward sharpening and fine edge potential, but final performance depends heavily on heat treatment and geometry.

Aogami vs Shirogami

The useful comparison is not “which is better?” but what trade-offs the maker has chosen. Aogami grades include alloying additions beyond the simpler Shirogami compositions, which can influence wear resistance and edge retention. Shirogami is often discussed for its simple carbon-steel composition and sharpening feel. In real knives, heat treatment and grind can outweigh small theoretical material differences.

SLD

SLD is a high-carbon, high-alloy tool steel often described as semi-stainless in kitchen-knife contexts. It can offer good wear resistance while requiring more corrosion awareness than a fully stainless household steel. Our modern Tadafusa knives use SLD cores with stainless cladding on selected models.

What does “clad” mean?

A clad blade combines a core steel at the cutting edge with outer layers of another steel. Stainless cladding around a carbon core can make everyday corrosion care easier because less reactive steel is exposed. The carbon core at the edge still needs attention.

What is Warikomi?

Warikomi is a construction method in which a harder core is inserted or enclosed within softer outer material. In practical product descriptions, pay attention to the stated core steel and cladding rather than treating the construction name as a quality score.

What is Damascus steel on a kitchen knife?

“Damascus” on modern kitchen knives usually describes a layered visual construction or cladding pattern. It does not tell you the exact core steel, hardness or cutting geometry. A Damascus knife can be excellent, but the pattern itself is not proof of superior performance.

What does HRC mean?

HRC is Rockwell C hardness. It provides useful context about how hard the blade has been heat treated, but it is not a complete performance score. Higher hardness can support thin, wear-resistant edges, while toughness, geometry and intended use remain important.

Does harder steel chip more easily?

Hardness is one factor in chipping risk, but not the only one. Edge thickness, grind, heat treatment, board material and technique all matter. Avoid using a thin fine edge for twisting, prying, frozen food or heavy bone.

Which steel is easiest to care for?

For many home cooks, a stainless steel such as VG10 is comfortable because corrosion resistance reduces the consequences of brief moisture exposure. Carbon steel can still be perfectly practical if you are willing to wash and dry promptly.

Which steel is easiest to sharpen?

Sharpening feel depends on alloy, hardness, heat treatment, stone and geometry. It is too simplistic to say one steel family is always easiest. Learn the existing bevel and use an appropriate stone progression.

How should you choose?

Start with care preference and knife type. If you want minimal corrosion attention, lean stainless. If you enjoy reactive carbon steel and its patina, Aogami or Shirogami may appeal. Then compare the actual knife's geometry, maker and intended use.

See the Knife Care Guide and Sharpening Guide.