Steel is one of the most common metals in shipbuilding. The most widely used is carbon steel, an iron-carbon alloy with a content of no more than 2%. Besides carbon, steel contains metallurgical impurities: manganese (up to 0.7%), silicon (up to 0.4%), sulfur (up to 0.05%) and phosphorus (up to 0.05%).
By designation, carbon steel is divided into structural (carbon content up to 0.6%) and instrumental (carbon content above 0.6%). Structural steel is distinguished from ordinary quality and quality.
Steels containing special elements (chromium, nickel, manganese, vanadium, etc.), besides iron and carbon, are called alloyed. The alloying elements improve the mechanical or physicochemical properties of the steel. The use of alloy steels can significantly reduce the mass of the hull and increase the ship's carrying capacity. Stainless steel does not give such savings because of its high cost.
Steel in shipbuilding is used in the form of sheets and profiles.
Sheet steel is mainly used to make the skin. In marine shipbuilding, sheet steel with a thickness of 6-30 mm with a width of 2-2.5 m and a length of 6-8 m is usually used.