In addition to iron and carbon, there are other alloying elements in round bars, and iron-carbon alloys are based on ordinary carbon steel, with an appropriate amount of one or more alloying elements. According to different added elements and processing technology, special properties such as high strength, high toughness, wear resistance, low temperature resistance, high temperature resistance, and non-magnetic can be obtained.
According to the total content of alloying elements, it is divided into:
In order to improve the performance of steel, on the basis of smelting carbon steel, the steel made by adding certain alloying elements is alloy steel, such as chromium steel, manganese steel, chromium-nickel steel, etc. It can also be called special steel, which has special properties such as high NMness, high wear resistance, high toughness, and corrosion resistance. Normally, elements such as Si, W, Mn, Cr, Ni, Mo, V, Ti and other elements are added to the steel.
According to the total amount of alloying elements, it can be divided into:
1) Low-alloy round steel - total content≤5%.
2) Medium alloy round bar - 5%~10% of the total amount of alloying elements.
3) High-alloy round bar - the total alloying element content > 10%.
According to the application, the steel grades are divided into:
1) Alloy structural steel: used for engineering components (pipes, brackets, etc.); All kinds of mechanical parts (shafts, gears, springs, impellers, etc.).
2. Alloy tool steel: used for measuring tools, molds, cutters, etc.
Special performance steels: such as stainless steel, heat-resistant steels, with special physical or chemical properties.