Steel is an alloy composed of iron and other elements, the most common of which is carbon. Carbon accounts for about 0.2% to 2. 1% of the weight of steel, depending on the grade of steel. Other alloying elements sometimes used include manganese, chromium, vanadium and tungsten. Together with other elements, carbon acts as a hardener, which can prevent the lattice dislocation of iron atoms, because these atoms slide past other atoms. By adjusting the amount and form of alloying elements (solute elements and participating phases) in steel, the characteristics of steel products, such as hardness, ductility and strength, can be controlled. Adding carbon steel will be harder and stronger than pure iron, but the ductility will be worse than iron.

Depending on the use of steel

I. Structural steel

Structural steel (1) Structural steel for building and engineering is referred to as construction steel for short, which refers to steel used for manufacturing metal structural parts in buildings, bridges, ships, boilers or other projects. Such as carbon structural steel, low alloy steel, strengthened steel, etc.

Structural steel for machinery manufacturing refers to the steel used for manufacturing structural parts on machinery and equipment. This kind of steel is basically high-quality steel or high-quality steel, mainly high-quality carbon structural steel, alloy structural steel, free-cutting structural steel, spring steel, rolling bearing steel and so on.

Second, the tool steel

Generally used for manufacturing various tools, such as carbon tool steel, alloy tool steel, high-speed tool steel, etc. According to the purpose, it can be divided into cutting tool steel, die steel and measuring tool steel

Three. special steel

Steel with special properties, such as stainless and acid-resistant steel, heat-resistant skinless steel, high-resistance alloy, wear-resistant steel, magnetic steel, etc.

Fourth, professional steel

This refers to the steel used in various industrial sectors, such as automobiles, agricultural machinery, aviation, chemical machinery, boilers, electricians and covered electrode.