Cast steel refers to the steel specially used for manufacturing steel castings. When the strength requirements of castings are high and the use of cast iron cannot meet the requirements, cast steel shall be used. However, the fluidity of molten steel of cast steel is not as good as that of cast iron, so the thickness of pouring structure should not be too small and the shape should not be too complex. When the silicon content is controlled at the upper limit, the fluidity of molten steel can be improved. Cast steel can be divided into general engineering cast steel, welding structure cast steel, stainless steel cast steel and heat-resistant steel cast steel according to its variety and purpose.
Cast steel is a kind of casting alloy, with iron and carbon as the main elements, and the carbon content is between 0-2%.
Cast steel can be divided into cast alloy steel and cast carbon steel according to its chemical composition, and can also be divided into cast tool steel, cast special steel, cast and cast alloy steel for engineering and structure according to its service characteristics.
By chemical composition
- Cast carbon steel. Cast steel with carbon as the main alloying element and containing a small amount of other elements. Cast carbon steel can be divided into cast low carbon steel, cast medium carbon steel and cast high carbon steel. The carbon content of cast low carbon steel is less than 0.25%, that of cast medium carbon steel is between 0.25% ~ 0.60%, and that of cast high carbon steel is between 0.6% ~ 3.0%. The strength and hardness of cast carbon steel increase with the increase of carbon content.Cast carbon steel has the following advantages: low production cost, high strength, good toughness and strong plasticity.Cast carbon steel can be used to manufacture parts bearing heavy loads, such as rolling mill frame and hydraulic press base in heavy machinery. It can also be used to manufacture parts with large stress and impact, such as wheels, couplers, bolster and side frame on railway vehicles.
- Cast alloy steel. Cast alloy steel can be divided into cast low alloy steel (the total amount of alloy elements is less than or equal to 5%), cast medium alloy steel (the total amount of alloy elements is 5% ~ 10%) and cast high alloy steel (the total amount of alloy elements is greater than or equal to 10%).
By usage characteristics
- Cast tool steel. Casting tool steel can be divided into casting tool steel and casting die steel.
- Special cast steel. Cast special steel can be divided into cast stainless steel, cast heat-resistant steel, cast wear-resistant steel, cast nickel base alloy, etc.
- Cast steel for engineering and structure. Cast steel for engineering and structure can be divided into cast carbon structural steel and cast alloy structural steel.
- Cast alloy steel. It can be divided into cast low alloy steel, cast medium alloy steel and cast high alloy steel.