Ship plates, namely hot - rolled steel plates used for manufacturing ship hull structures, are the core materials in shipbuilding. Their quality and performance are directly related to the safety, durability, and navigation performance of ships. Produced in accordance with the construction specifications of classification societies, in harsh marine environments, they need to withstand the impact of wind and waves, seawater corrosion, as well as the weight of the ship itself and its cargo.

• General - Strength Structural Steels: Under the specification standards of the China Classification Society, they are divided into four quality grades: A, B, D, and E. The yield strength of these four grades of steel is not less than 235N/mm², and the tensile strength is in the range of 400 - 520N/mm². The difference lies in the impact energy at different temperatures.

• High - Strength Structural Steels: In the specification standards of the China Classification Society, there are three strength levels and four quality grades. For example, for A32, D32, E32, and F32, the yield strength is not less than 315N/mm², and the tensile strength is 440 - 570N/mm²; for A36, D36, E36, and F36, the yield strength is not less than 355N/mm², and the tensile strength is 490 - 620N/mm²; for A40, D40, E40, and F40, the yield strength is not less than 390N/mm², and the tensile strength is 510 - 660N/mm².

• Mechanical Properties: It is required to have high yield strength and tensile strength, good toughness (sufficient impact energy), and plasticity (a certain elongation) to withstand various stresses and impacts during the ship's navigation.

• Corrosion Resistance: Being in the seawater environment for a long time, ship plates must have excellent resistance to seawater corrosion to prevent rust from affecting the service life and safety of the ship.
• Weldability: Welding processes are widely used in shipbuilding. Ship plates should be easy to weld to ensure the strength and tightness of welded joints.

• Formability: It should be able to adapt to processing operations such as cutting, bending, and stamping to form various ship hull structural parts.

  
  

General strength hull structural steel is divided into A, B, D, E4 grades, these four grades of steel yield strength (not less than 235N/mm^2) and tensile strength (400 ~ 520N/mm^2) the same, just different temperatures under the impact of the work is not the same;. High-strength hull structural steel according to its minimum yield strength divided into strength classes, each strength class is divided into A, D, E, F4 according to the different impact toughness. A32, D32, E32, F32 yield strength of not less than 315N/mm^2, tensile strength of 440 ~ 570N/mm^2, A, D, E, F, respectively, that their respective 0 °, -20 °, -40 °, -60 ° can be achieved under the circumstances of impact toughness. A36, D36, E36, F36 yield strength of not less than 355N/mm^2, tensile strength of 490 ~ 620N/mm^2, A, D, E, F, respectively, that each of their respective 0 °, -20 °, -40 °, -60 °, respectively, the impact toughness of the case can be achieved. A40, D40, E40, F40 yield strength of not less than 390N/mm^2, tensile strength of 510 ~ 660N/mm^2, A, D, E, F, respectively, that each of their respective 0 °, -20 °, -40 °, -60 °, respectively, can achieve the impact toughness of the situation