What is carbon steel alloy steel?

What is carbon steel  alloy steel?

The main raw material of iron making is iron ore, the main component of iron ore is Fe2O3,  there is no carbon; the second raw material of iron making is coke, part of the coke remains in the molten iron during the ironmaking process, resulting in carbon in the molten iron.

The production of iron  steel is made  iron ore to make pig iron,  pig iron is used as raw material to make steel; the process of steel making is mainly the process of carbon removal,  carbon cannot be removed completely. Steel needs a certain amount of carbon to achieve good performance.

In order to improve the properties of steel, some alloying elements need to be added on the basis of smelting carbon steel.

Pig iron (cast iron) - C is 2.0 to 4.5%

Steel (carbon steel) - containing C is 0.05 to 2.0%

Wrought iron (pure iron) - containing less than 0.05% C

iron ore → pig iron → steel

Therefore, steel is an alloy of iron with C (carbon), Si (silicon), Mn (manganese), P (phosphorus), S (sulfur),  small amounts of other elements.

In addition to Fe (iron), the content of C plays a major role in the mechanical properties of steel, so it is collectively referred to as iron-carbon alloys. It is an important  main amount of metal material in engineering technology.

According to carbon content, it can be divided into:

According to the carbon content, carbon steel is divided into low carbon steel, medium carbon steel  high carbon steel. With the increase of carbon content, the hardness of carbon steel increases  the toughness decreases.

1) Low carbon steel - carbon content ≤ 0.25%.

2) Medium carbon steel - carbon content > 0.25% ≤ 0.60%.

3) High carbon steel - carbon content > 0.60%

In order to improve the performance of steel, on the basis of smelting carbon steel, the steel made by adding some alloying elements is alloy steel, such as chromium steel, manganese steel, chromium manganese steel, chromium nickel steel, etc. Alloy steel, also known as special steel, has some special properties, such as high hardness, high wear resistance, high toughness, corrosion resistance  so on. Alloying elements often added to steel are Si, W, Mn, Cr, Ni, Mo, V, Ti, etc.

According to the total content of its alloying elements, it can be divided into:

1) Low alloy steel - the total content of alloying elements is less than  equal to 5%.

2) Medium alloy steel - the total content of alloying elements is 5% to 10%.

3) High alloy steel - the total content of alloying elements > 10%.