The alloy steel tees is made of alloy steel and a kind of iron carbon alloy consisting of one or more alloy elements added on the basis of ordinary carbon steel. According to the different elements, and appropriate processing technology, we can obtain high strength, high toughness, wear resistance, corrosion resistance, low temperature resistance, high temperature resistance, non-magnetic and other special properties.

The major alloying elements of alloy steel are silicon, manganese, chromium, nickel, molybdenum, tungsten, vanadium, titanium, niobium, zirconium, cobalt, aluminum, copper, boron, rare earth and so on. The vanadium and titanium, niobium, zirconium in steel is strong carbide forming elements, as long as there is sufficient carbon, under appropriate conditions, can form their own carbide when lacking carbon or under high temperature conditions, the atomic state into solid solution; manganese, chromium, tungsten, molybdenum carbide shape as one part of elements by atomic state into solid solution, another part of the formation of substitutional alloying cementite; aluminum, copper, nickel, cobalt and silicon carbide forming elements is not to the general state of atoms in solid solution.

Many kinds of alloy steel, usually according to the content of alloy elements is divided into low alloy steel (content < 5%), medium alloy steel (content 5% ~ 10%), high alloy steel (content > 10%); divided into high quality alloy steel, quality alloy steel; according to the characteristics and uses are divided into structural alloy steel, stainless steel and acid resistant steel, wear-resistant steel, heat-resistant steel, alloy tool steel, bearing steel, alloy spring steel and special steel (such as soft magnet, permanent magnet steel, non-magnetic steel etc.).