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 work is not the same;
High-strength hull structural steel according to its minimum yield strength divided into strength classes, each strength class and according to the different impact toughness is divided into A, D, E, F4.
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 impact toughness can be respectively in the case of 0 °, -20 °, -40 °, -60 ° can be achieved;
The yield strength of A36, D36, E36, F36 is not less than 355N/mm^2, the tensile strength is 490-620N/mm^2, and A, D, E, F indicate the impact toughness that each of them can achieve at 0°, -20°, -40°, -60° respectively;
A40, D40, E40, F40 have a yield strength of not less than 390N/mm^2 and a tensile strength of 510 to 660N/mm^2, and A, D, E, and F denote the impact toughness that each of them can achieve at 0°, -20°, -40°, and -60°, respectively.
