General strength steel for hull structures is divided into four grades: A, B, D, and E. The yield strength (not less than 235N/mm^2) and tensile strength (400~520N/mm^2) of these four grades of steel are the same. , it’s just that the impact energy is different at different temperatures; High-strength hull structure steel is divided into strength grades according to its minimum yield strength, and each strength grade is divided into A, D, E, and F4 grades according to its impact toughness.
The yield strength of A32, D32, E32 and F32 is not less than 315N/mm^2, and the tensile strength is 440~570N/mm^2. A, D, E and F respectively indicate that they can be used at 0°, -20°, Impact toughness that can be achieved at -40° and -60°;
The yield strength of A36, D36, E36, and F36 is not less than 355N/mm^2, and the tensile strength is 490~620N/mm^2. A, D, E, and F respectively indicate that they can be used at 0°, -20°, Impact toughness that can be achieved at -40° and -60°;
The yield strength of A40, D40, E40 and F40 is not less than 390N/mm^2, and the tensile strength is 510~660N/mm^2. A, D, E and F respectively indicate that they can be used at 0°, -20°, The impact toughness that can be achieved at -40° and -60°.