In essence, a kitchen knife is simply a piece of steel with a handle. A good kitchen knife is made of steel. Good steel should be considered as a base, a potential which, thanks to the processes of forging, bending and shaping the blade, can only be exploited by experienced craftsmen.

There are three main categories of steels used in the manufacture of kitchen knives. Each category has its advantages and disadvantages, depending on the use of the knife.

High Carbon Steels (Traditional Japanese Steels)
Corrosion resistant steels (VG10)
Powder steels (ZDP-189 or R2)

But before we dive into different types of steel, let's first explore the main chemical elements of steel and their effect on the characteristics of the kitchen knife.

CHEMICAL ELEMENTS IN STEEL AND THEIR EFFECT:

Steel is made up of iron (Fe), carbon (C) and smaller amounts of other elements. Carbon (C) is the key element in steel. Without carbon, steel could not be forged or bent. More carbon means harder steel. Steel can contain between 0.1 and 3% carbon.

CHEMICAL ELEMENTS:

Iron (Fe): main steel element. Carbon (C): key element in steel. This gives the steel the ability to be hardened during the heat treatment process. It reduces corrosion resistance and makes steel brittle. Chromium (Cr): greatly increases the corrosion resistance of steel and, at a certain level, increases its hardness. Manganese (Mn): improves the structure of the steel and increases the possibility of further hardening of the steel. Vanadium (V): the key element to increase the hardness of steel. This increases the possibility of having a sharper blade and maintains sharpness longer. Molybdenum (Mo): increases resistance to corrosion, it is often present in stainless steels and helps to maintain the hardness and strength of the steel in the event of temperature changes. Silicon (Si): increases the positive effects of carbon (C). This increases the hardness and strength of the steel. Cobalt (Co): for greater hardness and corrosion resistance. Tungsten (W): considerably increases the wear resistance of steel. Phosphorus (P): an impurity present in small quantities in all types of steel. Sulfur (S): impurity present in small quantities in all types of steel.

They can only be made by a few skilled artisans in Japan using the same method as the traditional Japanese sword. It is an art to work with traditional Japanese techniques, with exceptional sharpness and durability. The production is very small, due to the difficulty and time-consuming process. Having owned a few, these knives are amazing. If you are a collector or just a fan of Japanese kitchen knives, it is a must. Expensive certainly, but when you understand the essence of the work for the manufacture of this object, you realize that the price is only fair compensation for this masterpiece.

White steel is an extremely pure steel with a high percentage of carbon and no additional ingredients (it may contain phosphorus (F) and sulfur (S) as impurities). There are two types of white steel: white steel 1 and white steel 2. Forging white steel is extremely difficult and requires highly skilled craftsmen. A knife made from this steel has an extremely sharp edge, but it is brittle and susceptible to cracking.

White steel no.1 contains iron (Fe), carbon (C) 1.25-1.35%, manganese (Mn) 0.20-0.30%, phosphorus (P) 0 .03%, sulfur (S) at 0.004% and silicon (Si) at 0.10 to 0.20%. It is very popular with professional chefs preparing traditional Japanese cuisine because it can be refined to an extremely fine edge. It has a very good cutting edge and is easy to resharpen.

White steel no.2 contains iron (Fe), carbon (C) 1 – 1.15%, manganese (Mn) 0.20 – 0.30%, phosphorus (P) 0.03%, sulfur (S) 0.004% and silicon (Si) 0.10 – 0.20%. It has minimal impurities and a very fine grain structure, so it is ideal for fine cutting tools such as traditional Japanese style knives. It also has very good cut retention and is very easy to resharpen. Recommended for new users of traditional Japanese knives.

By adding chromium (Cr) to steel, we increase its resistance to corrosion. Chromium oxide forms a protective film on the surface of the steel, which prevents any contact between iron and water or oxygen. If the base steel alloy contains 12% or more chromium, we call it stainless steel. Even stainless steel kitchen knives should be wiped dry after use, especially if you are cutting fruits and vegetables that contain acids (lemon, onions, tomatoes, etc.). If we leave the knife dirty and wet for a long time, even the stainless steel can corrode.

Due to technological development, we have witnessed the emergence of new types of steels, which combine the quality of steel with a high percentage of carbon and the practicality of corrosion-resistant steel. High carbon (C) and corrosion resistant steels are popular with professional chefs today.

Contains iron (Fe), carbon (C) 1.40 – 1.50%, chromium (Cr) 0.30 – 0.50%, manganese (Mn) 0.20 – 0.30%, molybdenum (Mo) 0.30 – 0.52% and phosphorus (P) 0.03%, sulfur (S) 0.004%, silicon (Si) 0.10-0.20%, tungsten (W) 2.00 – 2.50% and vanadium (V) 0.30 – 0.50%.

It is one of the greatest Japanese carbon steels in terms of performance. In addition to containing more carbon, chromium and tungsten than blue steel No.1, it also contains molybdenum. It has very good sharpness and excellent edge retention. It is also capable of reaching high hardness without being brittle. Therefore, many knife enthusiasts rank aogami super among the best high carbon steels in the world.

Very high hardness up to 67 on the Rockwell C scale (HRC) and good toughness.

Satisfactory corrosion resistance.

Easy to sharpen steel, with a fine microstructure for a fine edge and the ability to stay sharper longer than other traditional steels.