Knife Blog

Since I wrote in the previous blog that I would introduce details of steel, I would do so this time.
 
There are two types of steel that are used for Japanese-style knives. One is carbon steel that is hardened while adding carbon into iron made by iron ore and iron sand. The other is stainless steel that resists rust by adding chrome into carbon steel. Generally, carbon steel is used for Japanese-style knives. There are several types of carbon steel set by contained amount of carbon. The more carbon iron has, the harder, sharper and more abrasion-resistant the iron is. However, the harder iron is, the more easily iron is broken and rusted.
 
It is Yasuki specialty steel that most Japanese-style knives are made of. Yasuki specialty steel is made by Hitachi Metals. Yasuki steel derives its name from the fact that it is made in Yasuki City in Shimane Prefecture.
 
The base of Yasuki steel is carbon tool steel. It is often used for at-home knives.
When fine iron sand is added on carbon tool steel, yellow steel is made. The yellow steel is also used for at-home knives.
 
When impurities are excluded from yellow steel, white steel II is made. This white steel II can be a great material for sharp knives.
 
When carbon is added on white steel II, white steel I is made. The white steel I is not very rare, but only a few of craftsmen can bring out the values of white steel I, so knives made of white steel I is very rare and valuable.
 
Features of knives made of white steel are that they are harder, sharper and sharpened more easily than knives made of stainless. However, they are more fragile and nicked more easily.
 
When chrome and tungsten are added on white steel II, blue steel is made. Chrome adds viscosity and tungsten adds abrasion resistance. When carbon is added on blue steel II, blue steel I is made. When carbon, chrome and tungsten are added on blue steel I, blue steel super is made.
 
White steel is more expensive than carbon tool steels. Blue steel is more expensive than white steel.