An alloy is a metallic material consisting of two or more base materials and combining their properties. Knives are made from a wide variety of different steel alloys.
Steel alloys for knives are developed according to the intended use of the knife. Depending on their composition, they offer very different properties and features. The exact properties of an alloy are determined by the following three factors: The first is the type and number of base materials, the second is their respective mass percentage within the alloy and the third is the temperature applied to combine the base materials. Steel alloys used in the knife industry can be classified into three major groups: German, Japanese and American knife steel. Each of these steel types includes countless alloys with very specific properties. Generally speaking, the differences between German, Japanese and American blade steel alloys are the result of different priorities in terms of knife production: While German knifemakers focus on corrosion resistance (rust resistance), Japanese knives need to be very sharp, American knives particularly sturdy.
German knife steel alloys contain chromium to achieve good corrosion resistance. In order to make the knife steel stainless, the alloy must contain a mass percentage of at least 13% chromium. Due to their high chromium content, German knives are significantly less hard compared to Japanese knives. Japanese steel has a high carbon content but contains very little chromium. The carbon makes Japanese knives harder and ensures a sharper edge, but the knives are not corrosion-resistant due to their low chromium content. American knife steel also contains chromium but is harder than German steel and thus more resistant to wear and tear. However, it is also more brittle than German knife steel and not as easy to grind.