Steels for machining

The combination of iron ore with other elements creates various types of steel that produce metal with different physical properties and for a wide variety of different applications, including machining steel.

There are different variations of steel compositions, but for the machining industry we can distinguish between 4 basic categories of steel (from least to greatest difficulty in machining):

1. Carbon steels: variety of steel that includes compositions with up to 2-3% carbon. The higher the% carbon, the greater the hardness and resistance. Steels in this category are generally easy to machine (they become more difficult to machine as the percentage of carbon increases).
2. Alloy steels: These steels are created by adding various amounts of additional elements to carbon steel. This will produce a steel with additional physical characteristics that cannot be found in normal carbon steel (higher hardness, corrosion resistance, …). There are a wide variety of elements that can be added to achieve a variety of enhanced characteristics, including: Manganese, Silicon, Nickel, and Copper to (increase strength), Chromium, Vanadium, Molybdenum, and Tungsten (improve appearance), nickel and copper (improve corrosion resistance), zirconium, cerium and calcium (increase toughness), lead, bismuth, selenium and tellurium (increase machinability).
3. Stainless steels: Chromium is the main element added to the composition (up to 10-20%) in the case of stainless steels. It is mainly used for an improved visual appearance and especially resistance to rust. It is a more expensive material and more difficult to machine.
4. Tool steels: This group of carbon steel and alloys is called tool steel because they are most often used to make tools for cutting and shaping other materials. Tool steels are extremely difficult to machine.