What types of steel are available
Dec 20, 2023
Steel is an alloy with iron and carbon as its main components, and its carbon content is generally less than 2,11 per cent. Steel is an extremely important metal material in economic construction.
Steel is divided into two categories according to the chemical composition of carbon steel (referred to as carbon steel) and alloy steel. Carbon steel is an alloy obtained by smelting pig iron, in addition to iron, carbon as its main component, but also contains a small amount of manganese, silicon, sulfur, phosphorus and other impurities. Carbon steel has certain mechanical properties, but also has good process performance, and low price. Therefore, carbon steel has been widely used. However, with the rapid development of modern industry and science and technology, the performance of carbon steel can not fully meet the needs, so people developed a variety of alloy steel. Alloy steel is based on carbon steel, purposefully adding certain elements (known as alloying elements) and get the multi-alloy. Compared with carbon steel, alloy steel performance has improved significantly, so it is increasingly widely used.
Because of the many varieties of steel, in order to facilitate the production, storage, selection and research, steel must be classified. According to the use of steel, chemical composition, quality of different, steel can be divided into many categories:
First, according to the use of classification
According to the use of steel can be divided into structural steel, tool steel, special performance steel three categories.
Structural steel:
1, used as a variety of machine parts steel. It includes carburised steel, tempered steel, spring steel and rolling bearing steel.
2, used as engineering structure of steel. It includes carbon steel in the A, B, special classes of steel and ordinary low alloy steel.
Tool steel: steel used to manufacture a variety of tools. According to the different uses of tools can be divided into cutting edge steel, mould steel and gauge steel.
Special performance steel: steel with special physical and chemical properties. Can be divided into stainless steel, heat-resistant steel, wear-resistant steel, magnetic steel.
Second, according to the chemical composition classification
According to the chemical composition of steel can be divided into two categories of carbon steel and alloy steel.
Carbon steel: according to the carbon content can be divided into low carbon steel (carbon content ≤ 0, 25%); medium carbon steel (0, 25% < carbon content < 0, 6%); high carbon steel (carbon content ≥ 0, 6%).
Alloy steel: according to the content of alloying elements can be divided into low alloy steel (total content of alloying elements ≤ 5%); medium alloy steel (total content of alloying elements = 5% - 10%);
High-alloy steel (total content of alloying elements >10%). In addition, according to the different types of major alloying elements contained in the steel, can also be divided into manganese steel, chromium steel, chromium-nickel steel, chromium-manganese-titanium steel and so on.
Third, according to the quality of classification
According to the steel in the harmful impurities of phosphorus, sulfur content can be divided into ordinary steel (phosphorus ≤ 0, 045%, sulfur ≤ 0, 055%; or phosphorus, sulfur content are ≤ 0, 050%); high-quality steel (phosphorus, sulfur content are ≤ 0, 040%); high-quality steel (phosphorus ≤ 0, 035%, sulfur content ≤ 0, 030%).
In addition, there are according to the type of smelting furnace, the steel is divided into flat furnace steel (acid flat furnace, alkaline flat furnace), air converter steel (acid converter, alkaline converter, oxygen top blowing converter steel) and electric furnace steel. According to the smelting degree of deoxidation, the steel is divided into boiling steel (deoxidation incomplete), sedentary steel (deoxidation more complete) and semi-sedentary steel.
Steel mills in the naming of steel products, often the use, composition, quality of the three classifications combined. For example, the steel is called ordinary carbon structural steel, high-quality carbon structural steel, carbon tool steel, advanced high-quality carbon tool steel, alloy structural steel, alloy tool steel and so on.
