There is a wide variety of materials used today to manufacture knife blades, all having advantages and disadvantages. Hardness, flexibility, corrosion resistance, sharpness and edge life are all affected by blade material.
Manufacturers decide what the blade thickness should be based on the
intended use. The thickness of the blade has the biggest affect on slicing.
The thinner the blade, the more flexible it will be and the thinner and more
precise the cut can be made
The edge of the knife, the ground edge that runs the length of the blade, is usually between ¼ to ½ inch wide. The thicker the edge,
the stronger it will be but the less sharp it will feel. The thickness of the cutting edge has the greatest affect on initial sharpness and edge life. Thinner edges are sharper and more fragile
Blades are available in ceramic, carbon steel, high carbon steel, stainless steel, high carbon stainless steel as well as specialty steel alloys.
Each material has properties that affect strength, flexibility, rust resistance and sharpness. In general, the harder the material, the stronger the edge will be and the longer the edge will remain sharp. The down side of hard blades is that they are more difficult to sharpen
Ceramic knives are made by heating zirconium oxide powder until the powder particles adhere to each other. Ceramic knives are very hard. They hold their edge longer than steel and are stain-proof and rust-proof. Ceramic does not impart any taste to food as steel knives can.
Ceramic knives do not have the flexibility of metal. The blade does not flex and any twisting or prying could snap it. Like other knives, a ceramic will eventually get dull, although it should take a longer time. When it does, it needs to be sharpened on a diamond stone. This is the only material hard enough to cut a new edge. They are hard enough and sharp enough to cut through the glaze on dinnerware and should only be used on cutting boards
CARBON STEELCarbon steel is iron with approximately 1% to 2% carbon. It holds an edge well, but is vulnerable to rusting. Some cooks use carbon steel because of their edge holding ability and sharpness; others feel that is not worth the trouble and extra care. Over time, a carbon-steel knife acquires a dark patina.
HIGH CARBON STEEL
Increasing the carbon content of steel increases the strength. Thus a knife blade made with high carbon steel will be stronger and stay sharp longer than just a carbon steel blade. Both carbon and high carbon steel will rust relatively quickly.
Stainless steel is made by alloying steel with materials such as chromium, molybdenum, and molybdenum, and only a small amount of carbon. Stainless steel blades do not retain a sharp edge very long. They are resistant to corrosion. Salt water and acidic foods can erode the protection and reduce the rust resistance of the knives
HIGH CARBON STAINLESS STEEL
This is a combination of high carbon steel and materials such as chromium, molybdenum, and molybdenum. This metal has the best attributes of high carbon steel and stainless steel. These blades are rust resistant and hold a sharp edge