Knife Steel

  • Stainless steel is an alloy of iron with a minimum of 10.5% chromium. Chromium produces a thin layer of oxide on the surface of the steel known as the “passive layer”. This prevents further corrosion of the surface. Increasing the amount of chromium increases resistance to corrosion.

    Additions of molybdenum also increase corrosion resistance in reducing acids and against pitting attacks in chloride solutions. Thus, there are numerous grades of stainless steel with varying chromium and molybdenum contents to suit the environment the alloy must endure. Stainless steel’s resistance to corrosion and staining, low maintenance requirements, and gorgeous lustre make it an ideal material for many applications where both the strength of steel and corrosion resistance are required.

  • Yes, stainless steel is “stain-less”, not “stain-impossible”. Stainless steel knives can rust under certain circumstances, but they are much more resistant to corrosion than ordinary carbon or alloy steels.

  • The Rockwell scale (also known as HRC) is a standard for comparing the hardness of steels. It measures hardness based on the depth of penetration of a diamond cone pressed into the material at a constant pressure. In short, the higher the number, the harder the steel.

    In general, SHAN ZU GYO Series and SHAN ZU PRO Series knives are made of premium Japanese steel with a hardness of 60–62 HRC, SHAN ZU Elite Series knives are made of 9Cr18MoV steel with a hardness of 57–59 HRC, and SHAN ZU Classic Series knives are made of X50CrMoV15 steel with a hardness of 55–57 HRC. An increase of 1 degree on the Rockwell scale equates to an increase in hardness of about 10%, as well as an increase in edge retention. These levels of hardness enable SHAN ZU knives to be thin and sharp without being overly brittle.

  • 9Cr18MoV and X50CrMoV15 are two different types of premium steel that SHAN ZU uses to make its blades. They differ in composition, including carbon, chromium, molybdenum, and vanadium.

    9Cr18MoV is a highly refined, high-carbon stainless steel with excellent hardness, edge retention, and durability.

    X50CrMoV15 contains less carbon than the other steel, so it has better weldability and rust resistance.